Scientific Fraud Growing Exponentially

Nowhere is the attack on science more evident than in the burgeoning incidence of scientific fraud, in the form of both falsification and fabrication of observational data. I first wrote about this in a blog post in 2019, since when the problem has only escalated. It’s now estimated that 1% to 2% of all scientific research papers are fraudulent – a fraud rate approaching that of industries such as healthcare and financial services.

A recent study from Northwestern University has examined scientific fraud in depth. Rather than the traditional focus on scientific misconduct by lone individuals, which is comparatively rare, the new study exposes numerous instances of large-scale fraud enabled by a far-flung network of editors and authors who cooperate to publish low-quality or fabricated research papers. This coordinated fraud combines clandestine “paper mills,” intermediary brokers, and so-called predatory journals that charge a fee without offering any services other than publication itself.

Paper mills are shady businesses that sell bogus manuscripts and authorships to researchers who need journal publications to advance their careers. The Northwestern researchers say that a 2022–23 survey of medical residents at hospitals in southwest China found that 47% of respondents had bought and sold papers, allowed other people to write their papers, or written papers for others.

A 2023 report in Nature magazine identified more than 400,000 research articles published over the previous two decades that show strong textual similarities to known studies produced by paper mills; the rising trend is illustrated in the figure below.

The new Northwestern study assembled an extensive database derived from major aggregators of the scientific literature, retracted publications, editorial records, and reports of image duplication in research papers.

A portion of the study focused on the massive online open access journal PLOS ONE, which has a higher-than-average retraction rate. The journal also lists the handling editor of every published paper. Of PLOS ONE editors who have accepted articles for publication, 22 accepted papers that were later retracted much more frequently than one would expect by chance. This number of flagged editors increased to 33 when mostly negative comments recorded by the watchdog PubPeer Foundation were considered.

Altogether, 45 PLOS ONE editors were flagged due to the anomalous rate at which they accepted eventually retracted or PubPeer commented publications, or because their submissions were handled by other flagged editors. Although these individuals edited only 1.3% of all papers published in PLOS ONE up to 2024, they edited a sizable 30% of the journal’s retracted papers. And 25 of these 45 editors themselves authored papers that were subsequently retracted.

These anomalous patterns are not restricted to PLOS ONE, say the Northwestern researchers. Across ten journals from the publisher Hindawi, which also disclose the editors of published manuscripts, they found 53 editors who accept eventually retracted articles anomalously often, and 96 who accept fast-tracked articles unusually frequently.

Apart from these examples of potentially fraudulent behavior, the study authors investigated whether certain scientific disciplines were more prone to fraud than others. It was found that the phenomenon is much more pronounced in six subfields in the area of RNA biology. As shown in the next figure, papers involving “lncRNAs” and “miRNAs, cancer” feature retraction rates that peak at around 4%, higher than even the rates of papers withdrawn due to errors.

Sadly, the authors conclude that scientific fraud is growing much faster than science as a whole. The number of retracted articles has been increasing exponentially over the last 30 years as seen in the figure below, in which the vertical scale is logarithmic and the dashed lines are projections.

The researchers note that the number of retracted articles and PubPeer commented articles have been doubling every 3.3 years and 3.6 years, respectively, while the total number of publications has doubled only every 15 years. The literature in some fields “may have already been irreparably damaged by fraud,” they say.

The Northwestern researchers go on to state:

Collectively, these findings show that the integrity of the extant scientific record and of future science is being undermined through the shortcomings in the very systems through which scientists infer the trustworthiness of each other’s work.

In the face of this onslaught, fortunately, the scientific community has not been silent. An informal network of research-integrity sleuths or paper-mill detectives now scrutinize thousands of published papers each year and frequently find evidence of manipulation and fabrication. Their detailed examinations, usually published online in PubPeer, often form the basis of subsequent retractions and misconduct investigations.

But sleuths and watchdog websites such as Retraction Watch can’t keep up with the rising tide of fraud. Lead author of the Northwestern study, Reese Richardson, is pessimistic about the future influence of AI (artificial intelligence):

If we're not prepared to deal with the fraud that's already occurring, then we're certainly not prepared to deal with what generative AI can do to scientific literature.

Next: Vaccine Hesitancy on the Rise

Sea Ice Not Currently Shrinking at Either Pole

To the surprise of many climate scientists, not only have the massive Antarctic and Greenland ice sheets stopped melting for now – as I recently documented (here and here) – but Arctic and Antarctic sea ice are not currently shrinking either.

As I discussed in an earlier post, the loss of Arctic sea ice has paused during the past two decades. Despite rising global temperatures, and contrary to alarmist projections of an ice-free summer by 2020, no statistically significant decline in Arctic summer minimum sea ice extent occurred between 2005 and 2024. Sea ice expands to its maximum extent during the winter and shrinks during summer months.

This unexpected trend has continued, with the minimum summer Arctic ice extent for 2025, reached on September 10, showing a slight uptick from 2024. The 2025 Arctic minimum extent is illustrated in the satellite-derived image on the left below.

The other two images above show the annual Arctic ice trend month by month, from January on the left to December on the right. The center image depicts the annual trend by year since 2014, while the image on the right compares 2025 with various intervals during the satellite era which began in 1979, and with the low-summer-ice year of 2012. The insets supply details about the ice extent on August 31, 10 days before this year’s minimum.

At the other end of the globe, Antarctic sea ice achieves its maximum in September during the southern winter and shrinks to its summer minimum extent in February. The left panel of the figure below shows a satellite image of the 2025 Antarctic maximum that occurred on September 18, just 8 days after the Arctic minimum. On the right is a 5-month plot of the ice extent for 2025 compared to 2024 and to the median extent from 1981 to 2010.

The historical behavior of Antarctic sea ice has been quite different from its North Pole counterpart. During the satellite era, rather than shrinking, the sea ice around Antarctica expanded steadily up until 2016, growing at an average rate between 1% and 2% per decade, with considerable fluctuations from year to year. But it took a tumble in 2017, as depicted in the figure below; this figure shows the February minimum, expressed as an anomaly relative to the 1981 to 2010 mean.

The overall trend from 1979 to 2025 is an insignificant 0.1% per decade relative to the mean. Yet a prolonged increase above the mean occurred from 2008 to 2017, followed by an eight-year decline since then. As can be seen in the graph, the summer ice minimum recovered briefly in 2020 and 2021, only to fall once more and pick up again in 2024 and 2025.

It appears that Antarctic summer sea ice extent has stabilized at a new, lower level over the past eight years. Yet the downward trend has sparked debate and several possible reasons for it have been advanced, not all of which are linked to global warming. One analysis attributes the big losses of sea ice in 2017 and 2023 to extra strong El Niños.

But a recent research paper paints a different picture. The mostly Australian authors point out that the abrupt decline in the Antarctic winter sea ice maximum since 2014 appears to have occurred 4.4 times faster than the decline in the Arctic sea ice maximum since 1979; the Antarctic winter sea ice loss over just the last decade is comparable to the winter sea ice loss in the Arctic over the whole 46 years of the satellite record. Both these effects are visible in part a of the figure below, in which the thin lines indicate possible linear trends.

Part b of the figure reveals that the decline in the Antarctic summer sea ice minimum since 2014 may have been 1.9 times faster than the summer sea ice decline in the Arctic since 1979. The researchers argue that the apparently more rapid decline in Antarctic summer sea ice, together with the fact that there is less summer sea ice surrounding Antarctica compared with the Arctic, means that if current trends were to continue, Antarctica could become essentially free of sea ice in summer sooner than the Arctic.

Such a regime change would have far-reaching consequences, they say, such as a feedback effect resulting in amplified Antarctic warming, and a slowing or collapse of the Antarctic Overturning Circulation – which in turn could induce more rapid melting of the Antarctic ice sheet.

However, the linear trends drawn in the figure above are misleading. The Antarctic summer sea ice minimum (thick blue line in b) should be compared with the previous figure, showing a pause in declining minimum ice extent since 2017. Likewise, the Arctic winter ice maximum (thick gold line in a) should be compared with the next figure, which shows the prolonged pause in Arctic sea ice loss between 2005 and 2024.

Next: Scientific Fraud Growing Exponentially

New Evidence Confirms That Sea Level Rise Is Not Accelerating

A blog post I wrote six years ago featured the lack of reliable scientific evidence at that time for any acceleration in the rate of average global sea level rise. Although several research reports since then claim to have found evidence that the rate of rise is accelerating, a new study puts the kibosh on that notion – and finds that the current rate of rise is less than half what is commonly accepted by climate scientists.

The study, by an engineer and researcher duo in The Netherlands, compiled sea level rise data from local observations worldwide, but mostly in the Northern Hemisphere, between approximately 1960 and 2020. The observations come from tide gauge records, which provide a more complete dataset than satellite altimetry that dates from only 1993.

It’s tide gauge measurements that matter to the local community and its engineers and planners. Tide gauges measure the height of the sea relative to the land to which the gauge is attached, the so-called RSL (Relative Sea Level) metric. Satellite observations of absolute sea level measure the height of the sea, which is the distance of its surface to the center of the earth. Land subsidence artificially amplifies any local RSL rise and makes satellite-measured sea levels higher than tide gauge RSLs.

The Dutch study used two datasets. The first, known as the PSMSL (Permanent Service for Mean Sea Level) provides historic records of monthly and yearly sea levels. The second dataset, called the GLOSS (Global Sea Level Observing System) provides hourly data; yearly mean sea levels are derived from the hourly data via so-called tidal analysis, which takes multi-year tidal forces into account. All data were downloaded in 2023, and only full years were utilized.

The PSMSL network consists of 1,533 locations for which data are recorded. Of these, only 204 locations met the study’s selection criteria of data being available over a period of at least 60 years, and for at least 80% of that period. The results are presented in the figure below. The rate of sea level rise is indicated by the color of the circles and triangles; triangles designate statistically significant acceleration of sea level rise, while circles designate non-significant acceleration. Statistical significance was determined by what is known as the F-test.

The acceleration is statistically significant in just 9 locations, or 4% of the total 204. Several of these locations form a cluster in Japan, while the remainder are solitary sites in Spain, Thailand, India, Australia and the Pacific. The meager amount of usable data in the Southern hemisphere is clearly visible.

Of the locations without significant acceleration, high rates of rise (up to 10 mm per year) are found in one location in the Pacific, in the US along the Gulf Coast, on the west coast of India, and in Japan, Thailand and Australia. Negative rates of rise, caused by rebound after melting of the last ice age’s heavy ice sheet, are found in the Baltic and along the west coast of Canada.

Similar but more limited results were obtained from the GLOSS network. Only 39 locations met the study’s selection criteria, and statistically significant acceleration is detected in a mere 3 of these. The highest rates of rise are found in the Pacific and Latin America, in this case coinciding with the locations showing acceleration.

Both datasets, nevertheless, yield a mean rate of sea level rise in 2020 considerably lower than NASA’s estimated 2020 rate of about 3.3 mm per year. For the more extensive PSMSL network, the 2020 median rate of sea level rise is found to be 1.5 mm per year as seen in the next figure, while the median rate for the GLOSS network is 1.9 mm per year.

The same overestimation of sea level rise rates can be found in reports of the UN’s IPCC (Intergovernmental Panel on Climate Change). In the figure below that compares the rise rates calculated in the Dutch study, from PSMSL data, with those in the IPCC Sixth Assessment Report, it can be seen that the IPCC’s median rate (blue line) is too high by about 2 mm per year compared with most of the actual observations.   

For both datasets, approximately 95% of the locations studied show no statistically significant acceleration of sea level rise. The study authors conclude that the accelerated sea level rise observed at the remaining 5% of locations can be explained by local, nonclimatic phenomena such as land subsidence or, in a few cases, plate tectonics. They say that the observed behavior is inconsistent with sea level acceleration driven by climate change.

Land subsidence arises predominantly from groundwater extraction, but also from mineral mining, rapid urban development that leads to compaction due to construction, and loading by river sediments.

Next: Sea Ice Not Currently Shrinking at Either Pole

Interloper Speeding Through Solar System Is Interstellar Comet, Not Alien Spacecraft

In early July, an observation made by a NASA-funded survey telescope in Chile sent the astrophysics community into a frenzy. The telescope, whose purpose is to search for objects that might collide with Earth, had discovered an intruder in our solar system – a stranger in our cosmic backyard, zipping along at speeds exceeding 210,000 km per hour (130,000 mph).

The initial consensus among astronomers was that the mystery object, named 3I/ATLAS after the Chilean telescope, was a comet from interstellar space, the third such object ever detected (3I standing for “3rd interstellar”). The evidence showed that its size was just a few km across and that it would not come closer than 270 million km (170 million miles) to Earth. But puzzling questions remained.

If the interloper was indeed a comet, why wasn’t it accompanied by the usual “tail,” the stream of gas and dust millions of km long stretching out behind a comet’s path? Why was it moving so fast, much faster than typical solar system comets? And why, contrary to most comets, was it traveling close to the so-called ecliptic, the orbital plane of Earth and most planets around the sun?

Enter famed Harvard astrophysicist Avi Loeb, recognized for his work on the evolution of the first stars. Rejecting the consensus, Loeb postulated that 3I/ATLAS could be an “extraterrestrial artifact” — maybe even an “alien mothership” on a reconnaissance mission through our solar system.

Loeb quickly submitted a preprint espousing his hypothesis, setting out his arguments for 3I/ATLAS being technological and possibly even hostile. One argument, put forward separately in a blog post of his, was that subsequent study of the extraterrestrial visitor by the Hubble space-based telescope suggested that it could now be producing its own light, as seen in the figure below.

The glow of light ahead of its motion had been interpreted by other astronomers as evaporation of dust from the sun-facing side of the object. But Loeb had a different interpretation: that 3I/ATLAS could be “a spacecraft powered by nuclear energy,” the dust emitted from its front surface being dirt that accumulated during its interstellar travel.

In his preprint, Loeb expounds his other arguments. Spectroscopic analysis has so far showed no sign of a cometary tail, essentially ruling out the comet hypothesis, he maintains. Furthermore, the interloper’s extremely high speed at its present large distance from the sun, which could give it a future gravitational “push,’’ means it cannot have come from the solar system. Most comets originate in the Kuiper Belt in the outer reaches of the solar system, but not beyond; 3I/ATLAS passed through the Kuiper Belt eight years ago, says Loeb.

As for its near alignment with the ecliptic plane, Loeb calculates that the probability of such a trajectory for an incoming object is a low 0.2%. In addition, the trajectory takes the unknown intruder unusually close to Venus, Mars and Jupiter, as indicated in the next figure, without coming too close to Earth. Assuming that 3I/ATLAS could have entered the solar system at any time, the probability of this trajectory is a vanishingly small 0.005%.

Loeb finds such estimates, together with other observations, suspicious. He speculates that the trajectory of 3I/ATLAS has all the hallmarks of an alien spacecraft dispatched to investigate the solar system while remaining beyond the range of our most powerful ballistic missiles.

Needless to say, other astrophysicists have found Loeb’s ideas outlandish – and for good reason.

On August 6, the awesome capabilities of the James Webb Space Telescope were brought to bear on the apparent trespasser, when the telescope’s near-infrared spectrograph was employed for a detailed study of the light emitted by the object. One of the many spectrograph images is displayed in the figure below, the arrow (S,v) denoting the direction of motion.   

The James Webb images show the light emitted by 3I/ATLAS much more clearly than the earlier pictures obtained by the Hubble telescope. The light pattern is in fact confirming evidence of the “coma” characteristic of a typical comet. A coma is the luminous halo of gas and dust that forms around the cometary nucleus as the comet approaches the sun; the coma appears as a diffuse “head” to the comet, the material eventually being swept into the comet’s tail.

What’s unusual about the coma of 3I/ATLAS is that it’s rich in CO₂ and has less water than most ordinary solar system comets. In another preprint, a research group headed by two NASA astrophysicists proposes that the comet contains ices exposed to higher levels of radiation than normal comets, accumulated as it traveled for probably billions of years through interstellar space, or that it formed close to the CO₂ ice line in another star system.

Even Loeb in his earlier preprint conceded that 3I/ATLAS was most likely a comet. He defended his paper as “largely a pedagogical exercise.”

Next: New Evidence Confirms That Sea Level Rise Is Not Accelerating

No Evidence That Jet Stream Waviness, Atlantic Ocean Overturning Becoming More Unstable

Despite the predictions of computer climate models that both atmospheric and ocean currents will weaken in a warming world, two recent papers (here and here) have found just the opposite.

Waviness in the polar jet stream, which is currently on the rise and plays a role in outbreaks of extreme winter cold in the Northern Hemisphere, is not as strong as it was in the 1940s, 1960s and 1980s, state three U.S. earth scientists in one paper. And a separate study concludes that the AMOC (Atlantic Meridional Overturning Circulation) has not declined for the past 55 years.

The jet stream is a narrow, high-altitude air current that flows rapidly from west to east in each hemisphere and governs much of our weather. It separates cold air toward the North or South Pole and warmer air on the equatorial side.

Inherently wavy due to the earth’s rotation and the temperature difference between low and high latitudes, the jet stream in winter becomes even wavier than normal. This leads to phenomena such as the well-known polar vortex which, in northern climes, causes long troughs of frigid air to descend from the Arctic.

Exceptionally large jet stream waves since the 1990s have prompted many climatologists to ascribe the behavior to global warming. But the three earth scientists say that this apparent volatility is not so unusual, and that the jet stream has undergone sporadic periods of enhanced waviness since before climate change was considered to be significant.

What the researchers did was to compile a record of the jet stream’s wintertime variability going back to 1901, by using AI to analyze long‐term climate data. Most previous studies concentrated only on the post-satellite era since 1979.

To their surprise, the analysis revealed that jet stream waviness from the 1940s to the 1980s surpassed modern waviness levels. So it’s highly unlikely that climate change has any influence on waviness.

The researchers also found that an extra strong wavy period lasting from the early 1960s to the 1980s, shown in the figure below, was the main driver of the “warming hole,” a prolonged period of abnormally cold winter temperatures in the U.S. that caused average winter temperatures to drop more than 1.3 degrees Celsius (2.3 degrees Fahrenheit). Their study estimates that pronounced jet stream waviness was responsible for two thirds of warming hole cooling between 1958 and 1988.

The AMOC, illustrated below, forms part of the ocean conveyor belt that redistributes seawater and heat around the globe. Exactly how global warming is changing the AMOC, if at all, is currently unknown. Alarmist proclamations in both the scientific literature and the mainstream media have suggested there are signs of the AMOC slowing, or even reaching a tipping point and shutting down altogether.   

Proxies that have been employed to reconstruct the past strength of the AMOC include sea surface temperatures, ocean density and salinity, ¹⁸O isotopes in sediment cores, and corals. Reconstructions based on several of these proxies have estimated declines in AMOC strength of up to 15% (see, for example, here and here).

But the new study finds no evidence of any slowdown in the AMOC since the mid-20th century, which is when the majority of today’s global warming began. The study’s multinational authors explain the discrepancy with earlier studies by pointing to the reliance of most such studies on sea surface temperature measurements. However, say the authors, sea surface temperature is not a reliable proxy for reconstructing the AMOC.

Instead, the new study focused on anomalies in air-sea heat fluxes in the North Atlantic Ocean, at latitudes between 26.5^oN and 50^oN. The air-sea heat flux is the amount of heat released from the ocean to the atmosphere; more heat is released when the AMOC is stronger.

The study authors used 24 different CMIP6 climate models to reconstruct the AMOC, by identifying a relationship between any change in the AMOC at a given latitude and the corresponding change in the air-sea heat flux north of that latitude in the North Atlantic basin. The adjacent figure presents some of their results, showing estimated changes in the AMOC from 1963 to 2017 at four different latitudes. The ERA5 and JRA-55 are different climate datasets.

No sign of any decline in the AMOC is seen during the 55-year period of the study, over the whole latitude range.

Additionally, the researchers found that when they looked for a relationship between AMOC changes and sea surface temperature in the same region, the trend was “not significantly different from zero” if they used the 24 CMIP6 climate models utilized in their own work. Many earlier studies that incorrectly predicted a weakened AMOC used now outdated CMIP5 models.

Next: Interloper Speeding Through Solar System Is Interstellar Comet, Not Alien Spacecraft

Challenges to the CO2 Global Warming Hypothesis (12): CO2 from Antimicrobials Far Exceeds CO2 from Fossil Fuels

My series on challenges to the CO₂ global warming hypothesis has featured a number of possible alternative sources to CO₂ as the source of warming, as well as scenarios that question the greenhouse effect. This post reports a new challenge that embraces the greenhouse effect and the CO₂ hypothesis, but disputes the belief that increased CO₂ comes primarily from burning fossil fuels.

The revolutionary proposal attributes the bulk of human CO₂ emissions into the atmosphere to a biological source, namely antimicrobials or, more precisely, antimicrobial resistance. This heretical idea comes from UK husband-and-wife team Frank and Jeanette Sams-Dodd, scientists with backgrounds in biology and veterinary medicine, respectively.

So what exactly are antimicrobials and how do they inject so much CO₂ into the air? Antimicrobials are simply chemical compounds that kill microbes. These include antibiotics, antiseptics, antifungals, antivirals, antiparasitics, disinfectants, surfactants, pesticides and herbicides.

Antimicrobial resistance occurs when microbes are able to withstand antimicrobials at the concentration they are exposed to in their environment. Use of antimicrobials eliminates nonresistant species, bolstering antimicrobial resistance and disrupting the microbiome. A microbiome is a community of bacteria and other microbes in the air, soil and water; everything on Earth has its own microbiome.

Disruption of microbiomes by antimicrobials, the Sams-Dodds explain, sets off a chain of events that leads to a severe imbalance in ecological systems that rely on a microbiome to release, absorb and retain certain gases, moisture and nutrients. This is illustrated in the figure below.

As indicated, antimicrobials find their way to sewage plants or landfills, from where they enter the wider environment unhindered, carried by water leaching through the soil. Antimicrobials are also carried by water that evaporates into the air, where they are transported through the atmosphere by winds and clouds before falling back to the earth as precipitation.

This widespread dispersal of antimicrobials is a major source of atmospheric CO₂.

As far back as 1954, it was shown that adding antibiotics to soil releases substantial amounts of CO₂ into the atmosphere. Several subsequent studies have confirmed that antimicrobials not only cause enhanced release of greenhouse gases, including CO₂, methane (CH₄) and nitrous oxide (N₂O), from soil and aquatic environments, but they also reduce carbon capture and storage. It is microbial communities that mainly regulate the earth’s carbon, nitrogen and other biogeochemical cycles.

To quantify the effect of antibiotics alone on CO₂ emissions, the Sams-Dodds have performed a detailed calculation of how a standard course of tetracycline affects the ability of soil to store carbon. They first estimate that the amount of tetracycline from a single course that escapes metabolic breakdown at a sewage treatment plant and is released into the environment is 2.0 grams.

They then draw on a 2023 study which found that 1.155 milligrams of tetracycline in soil reduces its storage capacity by 1.55 kilograms of carbon, or 5.68 kilograms of CO₂, per square meter of soil surface. Dividing 2,000 milligrams of tetracycline by 1.155 milligrams per square meter of soil surface equals 1,732 square meters. Multiplying by 5.68 kilograms of CO₂ per square meter gives a total of 9,835 kilograms (9.84 tonnes) of CO₂ released per course of tetracycline.

This calculation is based on data from cattle graziers, some of whom feed antibiotics to their cattle and some of whom don’t. A more realistic number for the reduction in carbon storage capacity worldwide from tetracycline use is a lower 3.82 kilograms of CO₂ per square meter of soil surface. When this number is multiplied by the area of fertile soil surface, which constitutes about 10% of the earth’s land surface, the reduction in long-term CO₂ storage capacity from tetracycline alone is 194.8 gigatonnes (214.7 gigatons).

What this means is that 194.8 gigatonnes (214.7 gigatons) of the CO₂ currently in the atmosphere, or about 6% of the total 3,341 gigatonnes (3,683 gigatons), would have been sequestered in soil were it not for the spread of human-made antimicrobials. More importantly, the CO₂ no longer stored in the soil is 5.2 times the estimated CO₂ emissions from fossil fuel combustion and industrial processes, of 37.6 gigatonnes (41.4 gigatons) in 2024.

So, if one subscribes to the CO₂ global warming hypothesis, CO₂ from fossil fuels makes only a minor contribution to warming; the major contribution by far comes from antimicrobial CO₂. Curbing fossil fuel emissions is therefore a fool’s errand.

Such a finding also turns on its head the conventional wisdom in the healthcare community that the increase in antimicrobial resistance over the last 70 years is a result of the CO₂-induced warming of approximately 1.25 degrees Celsius (2.25 degrees Fahrenheit) during that period. Rather, the Sams-Dodds conclude, the increase in antimicrobial resistance is responsible for the lion’s share of that warming.

The two scientists note that the rapid increase in the atmospheric CO₂ level since the late 1950s coincides with an upturn in use of both antimicrobials and fossil fuels.

Next: No Evidence That Jet Stream Waviness, Atlantic Ocean Overturning Becoming More Unstable

A Novel Geoengineering Strategy to Combat Sea Level Rise (2)

In the first part of this post, I described a revolutionary concept to offset global sea level rise by constructing a series of large deepwater lakes in arid environments such as Australia and the Sahara. In this second part, I’ll discuss further scaling up of the concept and some of the many engineering challenges involved.

The final figure in the previous post depicted the first of what Russ Walsh, the guiding force behind this strategy, calls “basic lakes,” 56 by 56 km (35 by 35 miles) in surface area and with depths up to 760 meters (2,500 feet). The next phase of the project would be more of the same – two more basic lakes, as shown in the figure below.

copyright © russ walsh

To hold even more seawater, Walsh envisions building even larger lakes further inland from the basic lakes: a “mega-lake” with a surface area of 100 by 225 km (60 by 140 miles), and a “super-lake” with a surface area of 160 by 240 km (100 by 150 miles). The depths of these massive lakes would range up to a staggering 1.6 to 8 km (1 to 5 miles). For comparison, a super-lake would be about two thirds the surface area of Lake Huron, the 2nd largest U.S. Great Lake, but considerably deeper. The average depth of the world’s oceans is about 3.7 km (2.3 miles).

Clearly, all this construction could not be done at once. The initial goal is to complete the first pilot lake by 2040, the first basic lake by 2050 and the massive mega-lake and super-lake by 2060-80.    

Among the many engineering questions that arise, the most important probably involve the sheer magnitude of the project. As Walsh himself admits, the total amount of earth to be moved will be unprecedented and could fill the Grand Canyon many times over. Past excavation of the Suez and Panama canals pales in comparison. Specialized large-scale digging equipment, from bulldozers to dump trucks and bigger than anything used in mining operations today, may need to be designed and built.

Digging such deep lakes will come with its own problems too, such as possible leaking of groundwater from aquifers or springs, or even flash floods, into the dig site before seawater is allowed to enter. Innovations in pumping and other measures could be necessary. A potential hazard is landslides, although these are more likely to be a problem in surrounding manmade hills than the carefully chosen slopes of the lakes themselves.

Another significant issue is exactly where to locate such a venture. As I’ve mentioned, the ideal location is a long stretch of flat, arid and mostly uninhabited coastal land – something not so easily found in practice. For example, much of the Sahara Desert, while sparsely populated, is unsuitable because it’s at too high an elevation.

A better prospect is Australia. With a vast landmass and a relatively small population, especially in the drier regions that characterize most of the continent, Australia has a geographical climate conducive to year-round construction. It also has a political climate that encourages the shipping of water to inland areas for both people and farming.

The next figure demonstrates just how thinly populated a large percentage of the country is (red and orange areas). And although it’s not evident from the figure, much of the coastline embracing the emptiness is at low elevations highly suited to the out-of-the-box thinking that Walsh espouses. He is currently in the process of identifying other, probably smaller tracts of land worldwide suitable for this gigantic undertaking.

Returning to the issue of repopulation, Walsh expects even the early phases of the project involving construction of pilot lakes to draw people to the region. Initially these would be construction workers, but later arrivals would include millions of others enticed by the prospect of living in a resort-like metropolitan area, replete with rail systems and other infrastructure, and hundreds of miles of walking, biking, and hiking trails. The larger, inland basic, mega- and super-lakes would likely be developed by the pilot lake areas’ new inhabitants.

Seawater lakes in the new settlements could conceivably support ocean habitats, and could serve as carbon sinks via mangroves along the lakeshore, coral reefs near the shoreline and floating kelp farms. New residents living on surrounding hills created by lake excavation could view sea creatures frolicking or watch sailboat races from their balconies and terraces.

While many such possibilities may seem fantasy, Walsh is realistic enough to have estimated the potential costs of the first stages of his venture, which are likely to range up to tens of billions of U.S. dollars. Nevertheless, he sees the project as ultimately yielding a positive ROI (return on investment) for investors, provided funding comes from private corporations rather than government sources.

Further details of both the project itself and its financing are contained in a soon-to-be-published book titled “The SeaNet Vision.”

Next: Challenges to the CO2 Global Warming Hypothesis (12): CO2 from Antimicrobials Far Exceeds CO2 from Fossil Fuels

A Novel Geoengineering Strategy to Combat Sea Level Rise (1)

In the ongoing debate over what to do, if anything, about rising global temperatures, adaptation has so far played second fiddle to mitigation. Grandiose geoengineering proposals to reflect the sun’s rays by injecting aerosols into the stratosphere or placing giant reflectors in orbit have been largely dismissed because of the unknown risks and possible unintended consequences of such moves.

But now a new geoengineering strategy with relatively benign and even beneficial consequences has been proposed by Russ Walsh, a California cybersecurity engineer: moving water from the world’s oceans to arid regions like Australia and the Sahara, in order to combat sea level rise.

Rising sea levels is a controversial topic. While there’s no doubt that the average global sea level has been increasing ever since the world started to warm after the Little Ice Age ended around 1850, no reliable scientific evidence exists that the rate of rise is currently accelerating over time, as is sometimes claimed. Nevertheless, the average sea level is currently going up at about 4.3 mm per year, according to NASA. If that continues for the next 50 years, the rise will be 21.5 cm (8.5 inches) – enough to cause serious problems and flooding in low-lying coastal areas.

Although extracting seawater from the oceans will be a massive and difficult project, it would avoid the problems of encroaching seas and the need to build seawalls all across the globe, or to eventually relocate nearly a third of the world’s population and infrastructure to higher ground.

The project would comprise four or five major components: pumping seawater from the ocean; possible desalination; transporting the water to its destination via waterways or canals; excavation of inland lakes to hold the water; and finishing work such as creation of surrounding hills or coastal protection with excavated earth.

Walsh is a visionary undaunted by the technical challenges of such an undertaking. With decades of experience working with major corporations, he is well connected with the types of companies his fledgling venture would need to work with to realize his vision. And he has bounced his concept off several of these companies, as well as water management experts and Stanford University engineering professors, all of whom have found it promising.

The concept is illustrated in the figure below, which shows schematically what the first phases of the project would entail. Built on an extended stretch of relatively flat, arid and mostly uninhabited land along the coastline, small test ponds and mini-lakes, ranging in surface area from 150 by 150 meters (500 by 500 feet) to 1.6 by 1.6 km (1 by 1 miles), would be connected to the nearby ocean via a dredged canal.

COPYRIGHT © RUSS WALSH

The next step would be excavation of a larger pilot lake, with a surface area of perhaps 8 by 8 km (5 by 5 miles), connected to the smaller lakes by the same canal. All lakes would of course have sloping sides, the exact slope determined by the local soil type and the need to avoid landslides. As indicated in the figure, pilot lakes could be as deep as 460 meters (1,500 feet) at their centers.

The following figure shows the next phase of proposed development, involving excavation of much larger “basic lakes,” now 56 by 56 km (35 by 35 miles) in surface area and with depths up to 760 meters (2,500 feet); a second canal would probably be required to help fill such large lakes. The enormous volumes of excavated earth could be used to create artificial hills in the region surrounding the lakes or to protect the coastline from erosion.

COPYRIGHT © RUSS WALSH

The lakes shown would all contain seawater, although a desalination plant could if necessary be placed near where the canals enter the ocean. The freshwater reservoir depicted in the first schematic figure above is an option, constructed on a nearby river which perhaps wends its way to the ocean through an existing town or seaport. If the river is large enough, the freshwater could be used to fill one of the planned basic lakes. Freshwater would be needed for any future residents of the lake area or for future farms in the same region.

Walsh in fact envisages the area surrounding the lakes as a kind of newly created oasis, a thriving transformed region drawing millions of residents and tourists. Many of the new arrivals might even live on the lakes themselves, in houseboats or possibly cruise ships. Even the initial pilot lake region would actually be about the size of the Las Vegas valley in Nevada, which is currently home to approximately 3 million people.

In the second part of this post, I’ll discuss further scaling up of this revolutionary concept, together with some of the engineering challenges and hopes of bringing the concept to fruition.

Next: A Novel Geoengineering Strategy to Combat Sea Level Rise (2)

Ice Sheet Update (2): Greenland Ice Sheet Loss Slows Down

Two big surprises have characterized recent warming-induced melting of the Antarctic and Greenland ice sheets. As I described in another post, the huge Antarctic ice sheet actually stopped melting – at least for now – and rebounded between 2021 and 2023, despite rising temperatures. And a new report highlights how the Greenland ice sheet in 2024 experienced its lowest annual ice loss since 2013.

Greenland’s ice sheet holds only about 10% as much ice as Antarctica’s. We hear more about it because the Greenland ice sheet is melting at a faster rate and contributes more to sea level rise. But the melt rate is no faster today than it was 90 years ago and appears to have slowed over the last few years.

The figure below shows the declining ice sheet mass from 2002 to 2024, based on NASA satellite data. In (a), the mass is shown relative to its value at the end of the spring/summer melt season in 2023, while (b) depicts the seasonal change in mass.

The average annual loss of ice between 2002 and 2023 was 266 gigatonnes (293 gigatons). As can be seen from the thick black line in (b), the 2023-24 loss was 55 gigatonnes (61 gigatons), the third lowest annual ice loss in the 23-year record; the thick green line is from a different satellite dataset. The report authors attribute the low ice loss in 2024 to above-average snowfall. Also apparent in (b) is that the Greenland ice sheet first increases in mass during winter months, due to snowfall, before losing mass over the warmer spring/summer months.

The extent of annual ice melting is illustrated in the next figure. Part (a) portrays the melt extent as a percentage of total ice sheet area for the 2023-24 melt season; part (b) shows the number of surface melt days from April 1 to August 31, 2024, expressed as an anomaly relative to the 1991-2020 mean.

The melt pattern in (a) hovers around the mean melt percentage from 1991 to 2020, indicated by the black line. This result on its own means that losses from the ice sheet are not accelerating, as is sometimes claimed. And (b) reveals that, while Greenland as a whole was still losing ice in 2024, the losses occurred primarily on the east coast of the island, with some ice buildup on the west coast. The report authors attribute this to persistent summertime low pressure over southern Greenland in 2024.

In addition to spring/summer melting, the ice sheet loses ice at its edges from calving or breaking off of icebergs, and from submarine melting by warm seawater. The report authors have estimated the rate of Greenland ice sheet discharge, which typically peaks in July and reaches a minimum in the fall. The figure below shows the annual rate of solid ice discharge from 1991 to 2024 in (a), and the monthly rate in (b).

It can be seen that the discharge rate sped up in the early 2000s, but has since leveled off. The mean discharge rate from 1991 to 2020 was 458 gigatonnes (505 gigatons) per year. Although the solid ice discharge rate during 2023-24 (thick blue line in (b)) exceeded the long-term mean (thin black line), it was not the highest in the record.

The next figure shows the average annual gain or loss of both the surface mass balance (in blue) and the total ice sheet mass (in black), going all the way back to 1840. The surface mass balance includes gains from snowfall and losses from melt runoff, but not sheet edge losses from calving glaciers. Most of the data comes from meteorological stations across Greenland.

The total mass in this graph includes the surface mass balance, iceberg calving and submarine melting (combined in the gray dashed line), and melting from basal sources underneath the ice sheet, but not peripheral glaciers – glaciers that contribute 15 to 20% of Greenland’s total mass loss.

You can see that the rate of ice loss increased temporarily in the early 2000s, as noted previously. But it’s also clear from the graph that high short-term loss rates have occurred more than once in the past, notably in the 1930s and the 1950s – so the current shrinking of the Greenland ice sheet is nothing remarkable. There’s no obvious correlation with global temperatures, since the planet warmed from 1910 to 1940 but cooled from 1940 to 1970.

The Greenland ice sheet is currently the second largest contributor to sea level rise, after thermal expansion of ocean water due to warming. If the rate of ice loss were to remain at its 2002 to 2023 average of 266 gigatonnes (293 gigatons) per year, which is an annual loss of about 0.01% of the total mass of the ice sheet, it would take another 10,000 years for all Greenland’s ice to melt.

Next: A Novel Geoengineering Strategy to Combat Sea Level Rise (1)

How Consensus Can Impede Scientific Progress

As I wrote several years ago (see here), a commonly misunderstood concept in science is the role of consensus. A scientific consensus is built by the slow accumulation of unambiguous pieces of empirical evidence, until the collective evidence is strong enough to become a theory.

Scientific consensus, however, is never reached by taking a poll of scientists. And a consensus isn’t necessarily the last word. A consensus, whether newly proposed or well-established, can be wrong. Failure to recognize this possibility has often held up progress in science.

A recent example comes from the field of archaeology. Throughout the 20th century, the predominant hypothesis was that humans first reached the Americas at the end of the last ice age about 13,000 years ago, when melting ice created a now submerged landmass known as Beringia, shown in the figure below. Asian hunters crossed from Siberia to Alaska, these so-called Clovis people (named after a unique type of spear point they used) subsequently migrating south along the edges of melting ice sheets to warmer climes. 

But despite evidence that the Clovis were not the first arrivals in the Americas, archaeologists who disputed the conventional wisdom were all but ignored and the sites they investigated were disregarded. Prominent among these naysayers was Canadian archaeologist Jacques Cinq-Mars, who carried out excavations at the Bluefish Caves in northwestern Yukon from 1977 to 1987.

Cinq-Mars and his team made an important discovery – bones of horses and woolly mammoths that exhibited cut marks from human butchering and toolmaking. Depicted on the left is a fragment from a horse’s jawbone showing deep thin cuts with a V-shaped profile, typical of butchery to remove muscle. Even more remarkably, radiocarbon testing dated the oldest finds to around 24,000 years ago, thousands of years before the Clovis people were thought to have been in the vicinity.

Reinforcement for Cinq-Mars’ new hypothesis about the first inhabitants of both North (and South) America came from another archaeological study in Washington state, where evidence was found for slaughtering and butchering of mastodons using all-purpose stone tools that resembled Exacto blades, during the same time period as the Bluefish Caves discoveries.

Another significant piece of evidence against the Clovis-first hypothesis was the discovery in Chile of “stone tools, remains of a large hide-covered shelter that may have housed 30 people, communal hearths, chunks of mastodon meat, and three human footprints,” the oldest of which was dated to 14,500 years in the past – again, before the Clovis even crossed Beringia.

Nevertheless, Cinq-Mars’ discovery was met with often acrimonious skepticism at the time, because the renegade archaeologist had dared to contest the prevailing consensus. His competence and sanity were constantly ridiculed and his conference presentations laughed at, experiences that he likened to questioning by the Inquisition. Eventually, even funding for his fieldwork dried up. Only now, some 40 years later, has the Clovis-first model become outmoded among most archaeologists and Cinq-Mars finally vindicated.

These ad hominem attacks on Cinq-Mars were no more virulent, however, than those directed earlier in the century at Alfred Wegener, the German meteorologist who proposed the revolutionary theory of continental drift.

Wegener was vehemently criticized by his peers because his theory threatened the geology establishment, which clung to the old consensus of rigidly fixed continents. One critic harshly dismissed his hypothesis as “footloose,” and geologists scorned what they called Wegener’s “delirious ravings” and other symptoms of “moving crust disease.” It wasn’t for almost 60 years that continental drift theory was accepted by mainstream geologists, after compelling evidence for the theory emerged.

These are not isolated examples in scientific history. Another, from the 19th century in the field of medicine, was the discovery of the now unquestioned importance of handwashing to prevent infection in hospitals. At that time, up to 10% of women who had their babies delivered by obstetricians used to die from so-called childbed fever shortly after childbirth.  In deliveries performed by midwives or at home, the death rate was several times lower.

A combative Hungarian obstetrician named Ignaz Semmelweis came up with the brilliant realization that hospital obstetricians weren’t washing their hands after carrying out barehanded autopsies on the pus-ridden bodies of women who had suffered an anguished death from the same disease only the day before. Once Semmelweis proposed that doctors wash their hands vigorously in a chlorinated lime solution after conducting autopsies, the mortality rate in obstetric wards plummeted.

But the discovery was widely rejected by the medical establishment of the day, whose consensus about disease was that it came from an imbalance in the four bodily humors of Hippocratic medical theory. Not until 20 years later, after Semmelweis had been beaten to death in an asylum, was his infection hypothesis vindicated by the newly accepted germ theory of disease. 

I’ve documented further examples of scientific progress being impeded by a mistaken mainstream consensus here.

Next: Ice Sheet Update (2): Greenland Ice Sheet Loss Slows Down

Ice Sheet Update (1): Reversal of Fortune for Antarctic Ice Sheet

The massive Antarctic ice sheet has long been a puzzle when it comes to global warming. Although the ice sheet is known to be shedding ice around its edges, past evidence has suggested that it may be growing in East Antarctica. Yet overall, the Antarctic ice sheet has melted enough to raise global sea levels by as much as 0.44 mm (17 thousandths of an inch) per year – until recently.

Now, a new study by Chinese earth scientists reveals what the researchers call an “astonishing rebound,” with the ice sheet growing – and no longer melting – for the first time in decades. The study was reported in a separate April news release.

The upper panel in the figure below shows changes in Antarctic ice sheet mass from April 2002 to December 2023, measured in billions of tonnes (gigatonnes, Gt where 1 gigatonne = 1.102 U.S. gigatons). The colored ovals indicate the rate of mass change for specific periods. You can see that while the loss rate accelerated during the two decades after 2002, the losses switched to an abrupt gain (positive rate of change) between 2021 and 2023. The data are based on satellite gravimetry, which measures the gravitational field across the earth’s surface.

The lower panel in the above figure shows the same data, but only until April 2023. In the image on the right, light blue shades indicate ice gain while orange and red shades indicate ice loss. White denotes areas where there has been very little or no change in ice mass since 2002; gray areas are floating ice shelves whose mass change is not measured by this satellite method.

Clearly, the ice loss was not uniform but was concentrated in West Antarctica, where melting of glaciers is significant and partly caused by active volcanoes underneath the continent. East Antarctica, on the other hand, had experienced modest amounts of ice gain, due to warming-enhanced snowfall, even before the recent abrupt gain for the continent as a whole.

To the surprise of the Chinese researchers, not only did the Antarctic ice sheet overall build up ice from 2021 to 2023 and possibly beyond, but so did four major glaciers in East Antarctica that were previously of concern because of their accelerating contributions to ice sheet loss. The large drainage areas of the four glaciers, which are in the Wilkes Land–Queen Mary Land region, are depicted by colored dots in the figure to the left above; the glaciers drain into the south eastern Antarctic coast.

Earlier reports had indicated that more glaciers in East Antarctica were starting to thaw and losing ice faster than anyone thought, say the study authors. In particular, the four glaciers just mentioned had exhibited increasing instability, with signs of ice thinning and extensive grounding line retreat, over the past two decades. Yet this pattern reversed and the four glaciers instead showed a significant gain in mass during the 2021 to 2023 period, as illustrated in the next figure.

The rate of total mass loss for the four glacier basins studied was 3.06 Gt per year for the period 2002–10, increasing dramatically to a loss rate of 50.70 Gt per year for the period 2011–20 – a loss rate acceleration far larger than that for the Antarctic ice sheet as a whole, shown in the upper panel of the first figure above.

This intensification of mass loss from the four glaciers is attributed by the researchers to a 27% increase in glacier ice discharge at the grounding line, combined with a 73% decrease in precipitation and sublimation from 2011 to 2020 in the Wilkes Land–Queen Mary Land region.

As for the contribution of Antarctic ice sheet mass change to global sea levels, the loss of 73.8 Gt per year during 2002–10 caused a sea level rise of 0.20 mm (8 thousandths of an inch) annually, while the increased loss of 142 Gt per year during 2011–20 caused a rise of 0.39 mm (15 thousandths of an inch) annually. In contrast, the annual ice gain of 108 Gt from 2021 to 2023 contributed a fall of 0.30 mm (12 thousandths of an inch) annually to global sea levels during those years.

In conclusion, it’s worth noting that the effect of global warming on Antarctic temperatures has been largely nonexistent. A 2019 study found that the average temperature in East Antarctica had shown no trend in 60 years, while the small Antarctic Peninsula - on the far west of the continent as shown in the figure below – had both warmed and cooled over the same period.

Next: How Consensus Can Impede Scientific Progress

Climate Model Track Record Improves Slightly: Paused Arctic Sea Ice Loss Predicted Correctly

As readers will know, I’ve been highly critical of computer climate models in these pages (see, for example, here and here). Some models greatly exaggerate future warming, or overestimate low cloud feedback, or are unable to reproduce observed sea surface temperature trends.

But a new study exonerates the models when it comes to predictions of sea ice loss in the Arctic, in particular the pause in loss of Arctic sea ice during the past two decades. Despite rising global temperatures, and contrary to alarmist projections of an ice-free summer by 2020, no statistically significant decline in Arctic summer minimum sea ice extent occurred between 2005 and 2024. Sea ice expands to its maximum extent during the winter and shrinks during summer months.

In correctly predicting this 20-year pause, the UK – U.S. collaboration partially redeems the same CMIP5 and CMIP6 models that have previously been shown incapable of accurately hindcasting the observed Arctic sea ice decline during the warming period of the early 20th century.

The present study also finds that periods with no sea ice loss while greenhouse gas emissions continue to increase are not at all unusual in large-ensemble CMIP5 and CMIP6 simulations. The modeling results suggest that internal climate variability – due to natural ocean cycles such as the AMO (Atlantic Multidecadal Oscillation), the PDO (Pacific Decadal Oscillation) or the NAO (North Atlantic Oscillation) – has offset any possible loss of Arctic sea ice due to human emissions.

The figure below illustrates the current robust and prolonged pause in Arctic sea ice loss, based on U.S. NSIDC (National Snow and Ice Data Center) data from satellite measurements, one of two key sea ice indices. The top panel shows the minimum summer ice extent in September over the satellite era from 1979 to 2024.

The center panel depicts 20-year trends during that time, the mean trend being a loss of 0.30 square km per decade, an amount that is not statistically significant despite the strong minimum in 2012; the red shaded envelope represents the 95% confidence level for statistical significance. The insignificant trend is approximately four times smaller than the peak 20-year sea ice trend recorded from 1993 to 2012. The bottom panel demonstrates how the current pause in Arctic sea ice loss shows up in every single month of the year, not just September.

The same effect of a drastic slowdown in Arctic sea ice decline is also evident in sea ice volume. The volume depends on both ice extent and thickness, which varies with location as well as season. Arctic ice thickness is notoriously difficult to measure, the best data coming from limited submarine observations.

According to the study authors, the loss of Arctic sea ice volume has stalled for at least the past 15 years, as shown by the shaded band on the left of the next figure. For the period 2010 to 2024, the simulated annual mean Arctic sea ice volume decreased by only 0.4 million cubic km per decade, a value that is seven times smaller than the long-term simulated loss from 1979 to 2024 of 2.9 million cubic km per decade, and again is not statistically significant.

Geographically, the sea ice volume loss is mostly evident in the Barents Sea, while the slowdown in September sea ice extent occurs mainly in the Pacific and Eurasian sectors. A satellite-derived image of total minimum Arctic sea ice extent is shown on the right of the above figure; the blue contour represents the median extent for 1991-2020.

As mentioned above, the new study has discovered that CMIP5 and CMIP6 climate models frequently simulate pauses in Arctic sea ice loss like the present one, rather than the past 20 years being an unexpected, rare event. Analysis of ensemble members that simulate the observed pause indicates that the current slowdown could possibly persist for a further five to ten years, say the study authors.

The following figure shows the percentage of ensemble members in various ensembles that have 2005-2024 September sea ice loss trends less than the observed value (note that the vertical label refers incorrectly to greater than). As can be seen, the multimodel average indicates that the chance of the ongoing pause in Arctic sea ice loss occurring at all is approximately 20%.

Although 20% is not 100%, the fact that climate models can make such a prediction is remarkable. Furthermore, the authors infer from the multimodel average that the present pause in September Arctic sea ice loss has a 1 in 2 chance of persisting for a further five years, and a 1 in 3 chance of persisting for another ten years.

In conclusion, the authors comment that their study is “a reminder that we should be humble about multidecadal predictions of the climate system, especially in highly variable regions such as the Arctic.”

Next: Ice Sheet Update (1): Reversal of Fortune for Antarctic Ice Sheet

AI Tries Its Hand at Climate Science

Much-ballyhooed AI (artificial intelligence), which is rapidly making inroads in many areas, has found its way into scientific publishing with the recent appearance of a peer-reviewed study featuring AI Grok 3 beta as the lead author. The 2025 paper, titled “A Critical Reassessment of the Anthropogenic CO₂-Global Warming Hypothesis,” disputes the narrative that global warming is largely driven by human emissions of CO₂.

Grok 3 beta, who wrote its own press release, spearheaded the research but needed critical guidance from four human coauthors. While the AI on its own was able to identify some of the relevant papers in the scientific literature, it fell short by missing a number of others and had to rely on its human colleagues to fill the gaps – and even they overlooked the work of one important researcher.

The study essentially reviews the conclusions of the IPCC (Intergovernmental Panel on Climate Change) regarding the global carbon cycle, computer climate models, and solar variability. The paper’s subtitle is “Empirical Evidence Contradicts IPCC Models and Solar Forcing Assumptions.”

On the carbon cycle, shown in the figure below, the study challenges the claim made in the IPCC’s AR6 (Sixth Assessment Report) that the effective residence time of CO₂ in the atmosphere is more than 100 years. The claim has been questioned by several authors, including Greek civil engineer Demetris Koutsoyiannis who, in a 2024 paper, estimated a residence time as short as 3.5 to 4 years.

The Koutsoyiannis paper simply divides the atmospheric CO₂ level, which was 416.4 ppm (parts per million) or 887 GtC (gigatonnes of carbon) in 2020, by the total flow of CO₂ into the atmosphere of approximately 230 GtC per year. However, this analysis only accounts for the so-called fast carbon cycle – the rapid movement of CO₂ between living organisms, the atmosphere and the oceans – but ignores the slow carbon cycle, in which CO₂ is incorporated into long-lived vegetation such as tree bark, or the deep ocean, or limestone and other rock.

Notable among other authors who share the beliefs of Koutsoyiannis are atmospheric scientists Hermann Harde and the late Murray Salby. Their work (see, for example, here) is acknowledged by Grok 3 beta, but only because the AI was reprimanded by its coauthors for omitting any mention of Harde or Salby papers from its first draft.

Another major omission the first time around was the extensive work of U.S. astrophysicist Willie Soon, one of the coauthors, on solar contributions to global warming. I’ll touch on Soon’s research below.

But more egregious than any of these omissions is Grok 3 beta’s failure to include any papers of physicist David Andrews, who has been highly critical of Harde and Salby.

Andrews (see here, here and here) distinguishes between the fast and slow carbon cycles, and points out that large, natural, two-way exchanges of carbon occur between the atmosphere, the oceans and land biomass. The fluxes each way exceed the one-way flux into the atmosphere of anthropogenic CO₂ from fossil fuels. Andrews also discusses errors in the interpretation of radiocarbon data in the Harde and Salby papers.

As for Koutsoyiannis, I discussed in a 2023 post how an earlier study of his is unable to explain 88% of the increase in atmospheric CO₂ during global warming of approximately 1 degree Celsius (1.8 degrees Fahrenheit) since 1880, in terms of CO₂ outgassing from the oceans.

Turning to climate models, Grok 3 beta gets it essentially right. As I’ve explained in numerous previous posts, many climate models run too hot, greatly exaggerating future global warming; only a small number come close to actual measurements. And a whole ensemble of models is unable to reproduce observed sea surface temperature trends in the Pacific and Southern Oceans since 1979.

Grok 3 beta correctly states that “model runs consistently fail to replicate observed temperature trajectories and sea ice extent trends, exhibiting correlations (R²) near zero when compared to unadjusted records.” On the subject of adjustments to raw temperature data, the paper also duly notes that such adjustments are contentious, especially the use of homogenization techniques which can introduce systematic errors into temperature data.

Finally, the AI rightfully draws attention to the IPCC’s questionable reliance on a single reconstruction of past solar output or TSI (total solar irradiance), to support its narrative of overwhelmingly human-caused global warming with essentially no contribution from the sun. As I described in another 2023 post, Soon and a team of coauthors have shown that a number of alternative TSI reconstructions, in which the sun plays a much larger role, can explain observed warming just as well as the IPCC’s chosen reconstruction.

So how well has Grok 3 beta mastered climate science? In this case, its paper is a mixed bag worthy of barely a passing grade.

Next: Climate Model Track Record Improves Slightly: Paused Arctic Sea Ice Loss Predicted Correctly

Math Teacher, Sole Climate Scientist Unlock Mystery of Recent Global Warming Spike

For the last two years it’s baffled climate scientists, who have been besides themselves trying to explain the apparent totally unexpected spike in recent global warming. Typical headlines in the media have included (see here, here, here and here):

What’s Causing the Recent Spike in Global Temperatures?

Charting the Exceptional, Unexpected Heat of 2023 and 2024

2023, 2024 climate change records defy scientific explanation

Scientists Stumped By 2024’s Heat Spike  

At a meeting of the American Geophysical Union in Washington, DC on December 10 last year, very few hands were raised when NASA climate scientist Gavin Schmidt asked how many attendees agreed that we understand why 2023 and 2024 were so hot. Asked a slightly different question, a majority of the audience concurred that an adequate explanation didn’t yet exist. Schmidt himself has used the phrase “uncharted territory” to describe the spike.

The spike can be viewed graphically in several ways. One way is by examining NOAA (the U.S. National Oceanic and Atmospheric Administration) satellite temperature data compiled by PhD meteorologist Roy Spencer and Alabama state climatologist John Christy:

The 2023-24 spike on the far right represents an extra strong El Niño, comparable to the one observed in 1997-98. The graph shows that the event raised the globally averaged temperature of the lower troposphere to a record 0.94 degrees Celsius (1.7 degrees Fahrenheit) above the 1991-2020 mean.

Another, perhaps more dramatic, way of viewing the spike is by plotting monthly temperatures for all years since 1880, compared to the preindustrial average, as depicted in the next figure. The warming surge during 2023 and 2024, which began with elevated global sea surface temperatures before the El Niño kicked in, stands out clearly.

But an Australian high school math (maths to Aussies) teacher who often comments on my blog can’t understand why everyone is so perplexed, saying that a very simple explanation exists – namely that the temperature spike was merely the result of an exceptionally strong El Niño superimposed on a steadily rising background due to global warming. The same effect will occur for any form of periodic variability.

The teacher, who goes by the screen name Braintic, points out that the phenomenon can be visualized mathematically by comparing the graph of the periodic function y = sin x with that of the function y = x + sin x, as shown in the figure below. Here x represents an assumed linear increase in global temperature with time, which may or may not be due to greenhouse gas emissions, and sin x represents periodic natural variability.

As Braintic emphasizes, the graph of y = x + sin x is a series of step increases superimposed on a rising trend. Exactly the same behavior can be seen in the first, satellite figure above.

In fact, such a staircase effect for global temperatures has actually been commented on before, by eminent New Zealand climate scientist Kevin Trenberth who made the following statement in an article published in July 2023, when the present spike was barely underway:

The combination of decadal variability and the warming trend from rising greenhouse gas emissions makes the temperature record look more like a rising staircase, rather than a steady climb.

Apparently, Trenberth’s prophetic comment – illustrated in the figure below – has gone unnoticed by his climate science colleagues, who have continued to make a mountain out of the proverbial molehill about the recent temperature surge. Trenberth remarks that the resulting temperature steps usually occur at the end of an El Niño event.

The staircase effect has been noticed by other scientists too, although none as perceptive as Braintic or Trenberth. In a 2024 blog post, I discussed a provocative hypothesis that links an upsurge in underwater seismic activity to recent warming.

The hypothesis was proposed by retired professor Arthur Viterito, whose starting point was the distinct step increases observed in satellite measurements of global warming, displayed in the first figure above. Viterito links these apparent jumps to geothermal heat emitted by volcanoes and hydrothermal vents in the middle of the world’s ocean basins. However, the explanation put forward here seems much more plausible.

Another revealing observation made by Braintic is that the magnitudes of the 1997-98 and 2023-24 El Niños are virtually the same, also contrary to the prevailing wisdom among climate scientists.

The Spencer-Christy satellite data shows that, for the 1997-98 El Niño, the background temperature anomaly (departure from the 1991-2020 mean) was -0.20 degrees Celsius averaged over the previous 10 years, and +0.35 degrees Celsius during the peak year of 1998. That’s a jump of 0.55 degrees Celsius.

For the 2023-24 El Niño, the background temperature anomaly was +0.23 degrees Celsius averaged over the previous 10 years, and +0.77 degrees Celsius during the peak year of 2024. That’s an almost identical jump of 0.54 degrees Celsius.

So two down-to-earth types from down under have solved a puzzle that has mystified hundreds in the climate science community!

Next: AI Tries Its Hand at Climate Science

Update: No Grand Solar Minimum Likely Anytime Soon

When empirical evidence doesn’t confirm the predictions of a hypothesis, the hypothesis is unequivocally wrong as emphasized in the header to this blog. But I’m guilty of ignoring this fundamental principle of the scientific method, in the aftermath of a blog post I wrote nearly five years ago titled “Upcoming Grand Solar Minimum Could Wipe Out Global Warming for Decades.” Within two years of the post it was clear that the evidence didn’t support this assertion, but I failed to recognize that until now.

In the post, I over emphasized the prediction of Northumbria University’s Valentina Zharkova that the sun was about to enter a period of diminished output known as a grand solar minimum – a prolonged cold stretch she estimated would last almost 35 years, in which global temperatures would drop by as much as 1.0 degrees Celsius (1.8 degrees Fahrenheit).

Her prediction was based on past observations of small dark blotches on the sun’s surface called sunspots, which are caused by magnetic turbulence in the sun’s interior and signal subtle changes in solar output or activity. Together with the sun’s heat and light, the monthly or yearly number of sunspots goes up and down during the approximately 11-year solar cycle, as can be seen in the figure below.

Zharkova observed that the maximum number of sunspots observed in a cycle had declined over several decades, from cycle 21 which peaked around 1980 to cycle 23 which peaked around 2000 (the 3rd and 5th peaks from the left in the figure above, respectively). A further drop in cycle 24 which peaked around 2015, and was the weakest cycle in 100 years, only served to reinforce her prediction of weaker yet future cycles: an upcoming grand solar minimum.

Zharkova’s prediction depended on a somewhat obscure statistical analysis, in which she linked grand solar minima that recur every 350 to 400 years to a drastic falloff in the sun’s internal magnetic field. The fluctuations in the solar magnetic field arise from regular variations in behavior of the very hot plasma powering our sun.

The last grand solar minimum occurred several centuries ago, the so-called Maunder Minimum from approximately 1645 to 1710, forming part of the Little Ice Age. Solar scientists have calculated that the sun’s heat and light output, a quantity known as the total solar irradiance, decreased by 0.22% during that minimum, which is about four times its normal rise or fall over an 11-year cycle.

The next figure depicts Zharkova’s calculated magnitude of the magnetic field from 1975 to 2040 that diminishes as her projected minimum approaches. On the basis of this calculation, she predicted that the peak sunspot number in cycle 25 would be 93, or 20% lower than the peak 116 in cycle 24 (the 1st and 2nd peaks from the right in the figure above, respectively), and 60% lower in cycle 26.

However, as pointed out by a persistent commenter on my original post, subsequent observations tell a very different story. Cycle 25 utterly refutes Zharkova’s prediction of a 20% lower peak than cycle 24, as is evident in the first figure above. Cycle 25 was already 16% stronger than cycle 24 two years ago, and the sunspot number is currently a whopping 158 or 70% stronger than cycle 24. So her prediction was badly off the mark and there’s no evidence of an impending grand solar minimum.

Other solar researchers have also predicted an imminent grand solar minimum, but for different reasons. One of the earliest predictions was by German astronomer and scholar, Theodor Landscheidt, in 2003. Landscheidt predicted a protracted cold period centered on the year 2030, based on his observations of an 87-year solar cycle known as a Gleissberg cycle.

A more recent prediction, based on a longer 210-year solar cycle, is that of Russian astrophysicist Habibullo Abdussamatov. He has projected a more extended period of global cooling than either Zharkova or Landscheidt, lasting as long as 65 years, with the coldest interval around 2043.

Clearly, these and other researchers who made the same claim were as mistaken as Zharkova. The myth of an approaching grand solar minimum was in fact debunked two years ago in a little-known post by prominent climate change skeptic Javier Vinós, who detailed the history of the myth and accused Zharkova and other climate scientists of misrepresentation to further their careers.

In conclusion, it’s worth noting that even the Solar Cycle 25 Prediction Panel, co-chaired by NOAA (the U.S. National Oceanic and Atmospheric Administration) and NASA, predicted in 2020 that the sunspot number in cycle 25 would be no higher than in cycle 24. Nonetheless, panel co-chair and solar physicist Lisa Upton said at the time: “There is no indication we are approaching a Maunder-type minimum in solar activity.”

Hat tip: Braintic

Next: Math Teacher, Sole Climate Scientist Unlock Mystery of Recent Global Warming Spike

Contribution of Low Clouds to Global Warming Still Controversial

A slew of research papers over the last year have attributed the so far unexplained surge in recent global warming to a decline in low cloud cover. But such a connection is still controversial. Several of the papers question their own conclusions or employ dubious methodology.

Prominent among these publications is a 2025 study by a trio of German environmental scientists. From satellite data, the authors claim to have pinpointed record-low planetary albedo, caused by a reduction in low clouds, as the primary source of the recent global temperature surge. The lowered albedo is most prominent in northern mid-latitudes and the tropics.

Albedo is a measure of the earth’s ability to reflect incoming solar radiation. Melting of light-colored snow and sea ice due to warming exposes darker surfaces such as soil, rock and seawater, which have lower albedo. The less reflective surfaces absorb more of the sun’s radiation and thus push temperatures higher.

The same effect occurs with low-level clouds, which are the majority of the planet’s cloud cover. Low-level clouds such as cumulus and stratus clouds are thick enough to reflect 30-60% of the sun’s radiation that strikes them back into space, so they act like a parasol and normally cool the earth’s surface. But less cloud cover lowers albedo and therefore results in warming.

The figure below shows global total and low cloud cover since 2000, calculated by the study authors from two separate sets of satellite data, indicated by the red and black curves, respectively. The decline in low cloud cover is as much as 1.5% – small, but large enough to raise global temperatures by 0.22 degrees Celsius (0.40 degrees Fahrenheit), say the scientists.

Furthermore, the disappearance of low clouds due to global warming sets up a positive feedback loop since fewer clouds cause more warming, which in turn lowers cloud cover even more. Nevertheless, the study authors cast doubt on their conclusions by pointing out that it is difficult to disentangle low cloud feedback from internal variability of the climate system and indirect aerosol effects. Long-term natural variability is associated with ocean cycles such as the AMO (Atlantic Multidecadal Oscillation).

As I discussed in a 2024 post, a major reduction in emissions of SO₂ (sulfur dioxide) since 2020, arising from a ban on the use of high-sulfur fuels by ships, can boost global warming. SO₂ reacts with water vapor in the air to produce sulfate aerosol particles that linger in the atmosphere and reflect incoming sunlight; they also act as condensation nuclei for the formation of reflective clouds. So the reduction in shipping emissions also contributes to the decline in low cloud cover.

More data linking the decline in low cloud cover to global warming is depicted in the next figure, showing cloud cover calculated from a different set of satellite data, and temperatures in degrees Celsius relative to the mean tropospheric temperature from 1991 to 2020.

A second 2025 paper, by two Chinese environmental engineers and a U.S. scientist, maintains that tropical low cloud feedback is positive rather than negative and 71% stronger than previously thought. Their conclusion depends on use of an obscure mathematical technique known as Pareto optimization, to reconcile large positive cloud feedback for the Atlantic Ocean in some global climate models with negative feedback for the Pacific in other models.

However, these authors concede that if warming is more uniform between cold stratocumulus regions and warm cloud ascent areas than they have assumed, then tropical low cloud feedback is likely to be much lower or even negative.

In a 2023 post, I reported on empirical observations, made by a team of French and German scientists, that refute the notion of positive low cloud feedback and show that the mechanism causing the strongest cloud reductions due to warming in climate models doesn’t actually occur in nature. Their conclusions were based on collection and analysis of observational data from cumulus clouds near the Atlantic island of Barbados.

In climate models, the refuted mechanism leads to strong positive cloud feedback that amplifies global warming. The models find that low clouds would thin out, and many would not form at all, in a hotter world. But the research team’s analysis reveals that climate models with large positive feedbacks are implausible.

Weaker than expected low cloud feedback is also suggested by lack of the so-called CO2 “hot spot” in the atmosphere, as I discussed in a 2021 post. Climate models predict that the warming rate at altitudes of 9 to 12 km (6 to 7 miles) above the tropics should be about twice as large as at ground level. Yet the hot spot doesn’t show up in measurements made by weather balloons or satellites.

Next: Update: No Grand Solar Minimum Likely Anytime Soon

Resumption of Blog Posts

I'm back! After recovering from back surgery for a fractured thoracic vertebra caused by my metastatic prostate cancer, I have now embarked on a treatment involving injections of radioactive radium-223 intended to kill cancer cells in my various bone metastases. As the side effects from the treatment are manageable, I'm glad to announce the resumption of my blog - at biweekly intervals, as before - from next week.

Suspension of New Blog Posts

It is with great regret that I’m suspending publication of further blog posts, at least temporarily, because of ill health. Two years ago I was diagnosed with stage 4 (metastatic) prostate cancer. Unfortunately, both the disease itself and some of the side effects from treatment have recently taken a turn for the worse, and I can no longer devote the necessary time to keeping up my blog.

However, the blog will remain accessible and you will be able to continue making comments on previous posts. I will endeavor to answer questions when I can.

Philippines Court Ruling Deals Deathblow to Success of GMO Golden Rice

Genetically modified Golden Rice was once seen as the answer to vitamin A deficiency in Asia and Africa, where rice is the staple food.  But a recent court ruling in the Philippines, the very country where rice breeders first came up with the idea of Golden Rice, has brought more than 30 years of crop development to an abrupt halt.

As reported in Science magazine, a Philippine Court of Appeals in April 2024 revoked a 2021 permit that allowed the commercial planting of a Golden Rice variety tailored for local conditions. The ruling resulted from a lawsuit by Greenpeace and other groups, who for many years have opposed the introduction of all GMO (genetically modified organism) crops as unsafe for humans and the environment.

Millions of poor children in Asia and Africa go blind or even die each year from weakened immune systems caused by a lack of vitamin A, which is produced in the human body through the action of a naturally occurring compound, beta-carotene.

So the discovery by Swiss plant geneticist Ingo Potrykus and German biologist Peter Beyer in the 1990s that splicing two genes – beta-carotene from daffodils, the other from a bacterium – into rice could greatly increase its beta-carotene content caused considerable excitement among nutritionists. Subsequent research, in which the daffodil gene was replaced by one from maize, boosted the beta-carotene level even further.

The original discovery should have been heralded as a massive breakthrough. But widespread hostility erupted once the achievement was publicized. Potrykus was accused of creating a “Frankenfood,” evocative of the monster created by the fictional mad scientist Frankenstein, and subjected to bomb threats. Trial plots of Golden Rice were destroyed by rampaging activists.

Nevertheless, in 2018, four countries – Australia, New Zealand, Canada and the U.S. – finally approved Golden Rice. The U.S. FDA (Food and Drug Administration) has granted the biofortified food its prestigious “GRAS (generally recognized as safe)” status. This success paved the way for the nonprofit IRRI (International Rice Research Institute) in the Philippines to initiate large-scale trials of Golden Rice varieties in that country and Bangladesh.

Greenpeace contends that currently planted Golden Rice in the Philippines will have to be destroyed, although a consulting attorney says there is nothing in the Court of Appeals decision to support that claim. And while Bangladesh is close to growing Golden Rice for consumption, the request to actually start planting has been under review since 2017.

The Philippines court justified its ruling by citing the supposed lack of scientific consensus on the safety of Golden Rice; the consulting attorney pointed out that “both camps presented opposing evidence.” In fact, the judges leaned heavily on the so-called precautionary principle – a concept developed by 20th-century environmental activists.

The origins of the precautionary principle can be traced to the application in the early 1970s of the German principle of “Vorsorge” or foresight, based on the belief that environmental damage can be avoided by careful forward planning. The “Vorsorgeprinzip” became the foundation for German environmental law and policies in areas such as acid rain, pollution and global warming. The principle reflects the old adage that “it’s better to be safe than sorry,” and can be regarded as a restatement of the ancient Hippocratic oath in medicine, “First, do no harm.”

Formally, the precautionary principle can be stated as:

When an activity raises threats of harm to human health or the environment, precautionary measures should be taken even if some cause and effect relationships are not fully established scientifically.

But in spite of its noble intentions, the precautionary principle in practice is based far more on political considerations than on science. A notable example is the bans on GMO crops by more than half the countries in the European Union. The bans stem from the widespread, fear-based belief that eating genetically altered foods is unsafe, despite the lack of any scientific evidence that GMOs have ever caused harm to a human.

In the U.S., approved GMO crops include corn, which is the basic ingredient in many cereals, corn tortillas, corn starch and corn syrup, as well as feed for livestock and farmed fish; soybeans; canola; sugar beets; yellow squash and zucchini; bruise-free potatoes; nonbrowning apples; papaya; and alfalfa.

One of the biggest issues with the precautionary principle is that it essentially advocates risk avoidance. But risk avoidance carries its own risks.

We accept the risk, for example, of being killed or badly injured while traveling on the roads because the risk is outweighed by the convenience of getting to our destination quickly, or by our desire to have fresh food available at the supermarket. Applying the precautionary principle would mean, in addition to the safety measures already in place, reducing all speed limits to 16 km per hour (10 mph) or less – a clearly impractical solution that would take us back to horse-and-buggy days.

Next: Contribution of Low Clouds to Global Warming Still Controversial

How Much Will Reduction in Shipping Emissions Stoke Global Warming?

A controversial new research paper claims that a major reduction in emissions of SO₂ (sulfur dioxide) since 2020, due to a ban on the use of high-sulfur fuels by ships, could result in additional global warming of 0.16 degrees Celsius (0.29 degrees Fahrenheit) for seven years – over and above that from other sources. The paper was published by a team of NASA scientists.

This example of the law of unintended consequences, if correct, would boost warming from human CO₂, as well as that caused by water vapor in the stratosphere resulting from the massive underwater eruption of the Hunga Tonga–Hunga Haʻapai volcano in 2022. The eruption, as I described in a previous post, is likely to raise global temperatures by 0.035 degrees Celsius (0.063 degrees Fahrenheit) during the next few years.

It’s been known for some time that SO₂, including that emanating from ship engines, reacts with water vapor in the air to produce aerosols. Sulfate aerosol particles linger in the atmosphere, reflecting incoming sunlight and also acting as condensation nuclei for the formation of reflective clouds. Both effects cause global cooling.

In fact, it was the incorporation of sulfate aerosols into climate models that enabled the models to successfully reproduce the cooling observed between 1945 and about 1975, a feature that had previously eluded modelers.   

On January 1, 2020, new IMO (International Maritime Organization) regulations lowered the maximum allowable sulfur content in international shipping fuels to 0.5%, a significant reduction from the previous 3.5%. This air pollution control measure has reduced cloud formation and the associated reflection of shortwave solar radiation, both reductions having inadvertently increased global warming.

As would be expected, the strongest effects show up in the world’s most traveled shipping lanes: the North Atlantic, the Caribbean and the South China Sea. The figure on the left below depicts the researchers’ calculated contribution from reduced cloud fraction to additional radiative forcing resulting from the SO₂ reduction. The figure on the right shows by how much the concentration of condensation nuclei in low maritime clouds has fallen since the regulations took effect.

The cloud fraction contribution is 0.11 watts per square meter. The other contributions, from a reduction in cloud water content and the drop in reflection of solar radiation, add up to a total of 0.2 watts per square meter extra radiative forcing averaged over the global ocean, arising from the new shipping regulations, the NASA scientists say.

The effect is concentrated in the Northern Hemisphere since there is relatively little shipping traffic in the Southern Hemisphere. The researchers calculate the boost to radiative forcing to be 0.32 watts per square meter in the Northern Hemisphere, but only 0.1 watts per square meter in the Southern Hemisphere. The hemispheric difference in their calculations of absorbed shortwave solar radiation (near the earth’s surface) can be seen in the following figure, to the right of the dotted line.

According to the paper, the additional radiative forcing of 0.2 watts per square meter since 2020 corresponds to added global warming of 0.16 degrees Celsius (0.29 degrees Fahrenheit) over seven years. Such an increase implies a warming rate of 0.24 degrees Celsius (0.43 degrees Fahrenheit) per decade from reduced SO₂ emissions alone, which is more than double the average warming rate since 1880 and 20% higher than the mean warming rate since 1980 of approximately 0.19 degrees Celsius (0.34 degrees Fahrenheit) per decade.

The researchers remark that the forcing increase of 0.2 watts per square meter is a staggering 80% of the measured gain in forcing from other sources since 2020, the net planetary heat uptake since then being 0.25 watts per square meter.

However, these controversial claims have been heavily criticized, and not just by climate change skeptics. Climate scientist and modeler Zeke Hausfather points out that total warming will be less than the estimated 0.16 degrees Celsius (0.29 degrees Fahrenheit), because the new shipping regulations have only a minimal effect on land, which covers 29% of the earth’s surface.

And, states Hausfather, the researchers’ energy balance model “does not reflect real-world heat uptake by the ocean, and no actual climate model has equilibration times anywhere near that fast.” Hausfather’s own 2023 estimate of additional warming due to the use of low-sulfur shipping fuels was a modest 0.045 degrees Celsius (0.081 degrees Fahrenheit) after 30 years, as shown in the figure below.

Further criticism of the paper’s methodology comes from Laura Wilcox, associate professor at the National Centre for Atmospheric Science at the University of Reading. Wilcox told media that the paper makes some “very bold statements about temperature changes … which seem difficult to justify on the basis of the evidence.” She also has concerns about the mathematics of the researchers' calculations, including the possibility that the effect of sulfur emissions is double-counted.

Next: Philippines Court Ruling Deals Deathblow to Success of GMO Golden Rice