The Heritage Foundation recently published a paper from the leading scientists at the Center for Environmental Research and Earth Sciences (CERES) that argues the debate over the causes and consequences of climate change is not settled, in part because the climate models likely fail to account for problems with the temperature record and the influence of solar activity on climate.

Concerning the temperature record, the paper points out there are three principal sources of local temperatures that are averaged and combined to produce "global average temperatures," surface stations, which include both land-based and ocean-based temperature readings, satellite measurements, and weather balloon measurements. The paper describes how average readings are determined and communicated. The problem identified by CERES, a problem others have pointed to previously, including repeatedly by Anthony Watts, is that the surface temperature record is beset by persistent the heat bias stemming from surface stations being improperly located.

CERES shows that the UN Intergovernmental Panel on Climate Change (IPCC) fails to adequately address this and other problems associated with the surface station record, as displayed in contaminated homogenized temperature datasets. CERES' research suggests that the IPCC's temperature "data" is as much as 40 percent warmer than it would be were the bias from the urban heat island effect and flawed homogenization properly accounted for.

Concerning natural factors that impact climate, the IPCC only modeled two natural factors, ignoring a number of others: volcanic activity and solar irradiance (solar activity). Interestingly, despite CERES identifying a minimum of 27 different estimates of long-term solar irradiance since 1850, the IPCC chose to only examine one estimate, one that just happened to suggest that the Sun did not play a measurable role in recent climate change. Other estimates show a larger impact on temperatures, both decadal and over longer time scales. As CERES writes:

We ... have concerns about the IPCC's handling of the ongoing scientific debate over the changes in solar activity (TSI) since 1850. The TSI estimate used by the computer model simulations that contributed to the IPCC analysis was guaranteed to show that global warming was "mostly human-caused." However, we have identified at least 27 different estimates of the changes in TSI since 1850. Several of these estimates suggest that global warming is "mostly natural," and several suggest that global warming is a mixture of natural and human-caused factors.

In the end, the IPCC's claims that the science is settled and that human activity, not nature, is responsible for all or the vast majority of present climate change was seemingly pre-ordained by the data sets the IPCC chose. This indicates the IPCC knew the outcome it wanted and tailored its premises to produce it. Per CERES:

We therefore conclude that the IPCC was overconfident and premature in its detection and attribution statements. The scientific debate remains ongoing. In our opinion, the scientific community is not yet in a position to establish whether the observed temperature changes since the 1800s are "mostly natural," "mostly human-caused," or "a mixture of both."

The scientific debate about how much global warming is manmade and how much is natural has not been resolved.

Source: The Heritage Foundation

Two recent studies reinforce the fact that climate model simulations are wholly inadequate to project climate change and thus, policy makers should not trust such projections to shape policy.

It is widely acknowledged that climate models run too hot and have historically produced false impact projections. The simple fact is scientists don't understand all the factors that impact temperatures and climate, which becomes more evident with every new journal publication.

I have written dozens of times describing research detailing factors unaccounted for by climate models that likely account for some of the discrepancies between model outputs and reality. Last week, in Climate Change Weekly, I discussed research suggesting that oceans remove far more carbon dioxide from the atmosphere than previously believed, and assumed in climate models.

Two new peer-reviewed studies point to other factors impacting climate that models fail to account for.

Research published in the journal Science Advances quantifies emissions of sulfur gas produced by marine life that cools the climate more than previously believed.

The study produced through the collaboration of an international team of 14 scientists from universities and research institutes located in eight countries spanning three continents examined dimethyl sulfide outgassing produced by microscopic plankton living on or near the ocean surface. They found that the sulfur emissions were substantial and contribute to forming aerosol particles that directly reflect sunlight back into the atmosphere and that contribute to cloud formation and brightening, which also reflects sunlight. This dual action has a cooling effect on the Earth's surface.

Commenting on the importance of this study to an accurate analysis of climate change, Charel Wohl, Ph.D., lead author of the study from the University of East Anglia's Centre for Ocean and Atmospheric Sciences said:

This is the climatic element with the greatest cooling capacity, but also the least understood. We knew methanethiol was coming out of the ocean, but we had no idea about how much and where. We also did not know it had such an impact on climate.

Climate models have greatly overestimated the solar radiation actually reaching the Southern Ocean, largely because they are not capable of correctly simulating clouds. The work done here partially closes the longstanding knowledge gap between models and observations.

Research published in the journal Nature indicates that models also fail to account for emissions from rainforests, which also tend to cool the climate.

The research by scientists from Finland in collaboration with 80 scientists from universities and research institutes in 11 different countries finds that rainforests emit chemicals that form isoprene-oxygenated organic molecules, with said molecules reaching the troposphere. The atmospheric gases were discovered by aircraft observations, and have been confirmed in laboratory simulations, and by global satellite measurements.

These particles grow and contribute to cloud cover and rainfall, especially over rainforests, ultimately regulating the regional and global climate. Based on laboratory experiments carried out in the European Organization for Nuclear Research's (CERN) Cosmics Leaving Outdoor Droplets (CLOUD) chamber, the research team determined that isoprene emitted by rainforests drives rapid particle formation in extensive regions of the tropical upper troposphere resulting in tens of thousands of particles per cubic centimeter, and ultimately growth on the right atmospheric conditions. This is important because:

Aerosol particles are important for climate because they scatter and absorb incoming solar radiation and seed cloud droplets by acting as cloud condensation nuclei (CCN). More CCN make clouds more reflective and may increase their extent and lifetime. Around half of CCN globally, and almost all in the upper troposphere6, arise from new particle formation ....

Commenting on the study in a news story, Marc Morano, who runs the popular climate change analysis site, Climate Depot, told KTRH 740 AM, Houston, "The amazon rain forests are essentially cloud machines ... they're pumping out clouds by releasing these aerosols from the forest.

"Which then create more clouds, which then cool the earth," Morano continued. "Clouds are not accounted for well in the climate models, and this is what every skeptical scientist has been saying for decades."

So, to sum up, three studies published in just the past month have suggested separate factors that impact temperatures, moisture, and climate change more generally - with none of those factors being accounted for by climate models, which have persistently failed over the decades to accurately reflect temperatures. Based on this alone, not even considering the solar irradiance issues raised by CERES discussed above, it is fair to say the science is not settled concerning causes and consequences of climate change.

Sources: University of East Anglia; Science Advances; Climate-Science Press; Nature; Science Direct

In a recent study published in the Journal of Sustainable Development, Michael Simpson from the University of Sheffield, points out that the goal of hitting net zero emissions is a political one, that was undemocratically adopted by the U.K. government. It is not grounded in science.

Simpson's study goes through the chemistry and physics of greenhouse gases, arguing that there is no climatic reason for reducing the emissions of greenhouse gases to net zero. Even if that goal is politically possible, carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O), are saturated in the atmosphere. As a result, per Simpson, "[a]dding to or removing these naturally occurring gases from the atmosphere will make little difference to the temperature or the climate."

Simpson first explains the mechanism by which net zero was adopted by the U.K. government and what it would mean for its economy. He writes:

The economic consequences of pursuing Net Zero are thought to be devastating for the UK with estimates of costs up to £1.4 trillion for the UK alone offset by £1.1 trillion potential but dubious savings giving a net cost of £321 billion (385.2bn USD) or a cost of £10bn a year rising to £50bn a year according to the UK Climate Change Committee (https://www.theccc.org.uk/publications/). Recent reports (NESO, 2024) clearly show that Net Zero does not pass the cost-benefit test (Montford, 2024b) and is likely to cost each household in the UK £78,000 to decarbonise power generation and £58,000 to decarbonise road transport between now and 2050. With investment costs alone of £40bn per annum to 2050. All this expenditure, ~£300,000 per household in total, will be paid for by taxpayers, consumers, and businesses or through national debt for future generations to pay for (Sasse, 2021). This will hurt the poorest and most vulnerable in society the most, increasing household bills by several thousand pounds a year.

Yet all of this pain would produce no gain in terms of benefits to the U.K. or the world. As Simpson points out doing a brief literature review, there is no evidence that climate change is causing an increase in extreme weather events or making such events worse, more severe, of greater duration, or more powerful. In short, there is no evidence that human greenhouse case emissions are causing dangerous climate change.

And, indeed, Simpson notes, they shouldn't be because scientific theory and experimentation show the vast quantity of naturally occurring water vapor (H2O) in the atmosphere covers the radiation absorption band of solar radiation. Additions to atmospheric greenhouse gas concentrations from humans don't significantly alter the amount of solar radiation that can be absorbed and retained. On this point, as with others, Simpson contributes no original research. Rather, he gathers and nicely summarizes the research conducted by scientists such as physicists Will Happer (Princeton) and Steve Koonin (New York University), and geologist Ian Plimer (University of Melbourne).

Instead of simply appealing to authority on this point, Simpson also goes through the "ideal gas law" in detail, showing mathematically why additional greenhouse gases can't have the climatic impact attributed to them by the UN Intergovernmental Panel on Climate Change. Based on these facts, since greenhouse gases aren't producing runaway temperatures or worsening weather, they can't be causing a climate crisis in need of a big government fix. As a result, Simpson concludes:

There is a case against the adoption of Net Zero given the enormous costs associated with implementing the policy, and the fact it is unlikely to achieve reductions in average near surface global air temperature, regardless of whether Net Zero is fully implemented and adopted worldwide. Therefore, Net Zero does not pass the cost-benefit test. The recommended policy is to abandon Net Zero and do nothing about so-called 'greenhouse gases.'

H. Sterling Burnett, Ph.D., is the Director of the Arthur B. Robinson Center on Climate and Environmental Policy and the managing editor of Environment & Climate News.