Climate Study: Evidence Leans Against Human-Caused Global Warming
On Tuesday, a group of 50 international scientists released a comprehensive new report on the science of climate change that concluded that evidence now leans against global warming resulting from human-related greenhouse gas emissions.
The report, which cites thousands of peer-reviewed articles the United Nations-sponsored panel on climate change ignored, also found that "no empirical evidence exists to substantiate the claim that 2°C of warming presents a threat to planetary ecologies or environments" and no convincing case can be made that "a warming will be more economically costly than an equivalent cooling." The U.N.'s panel is scheduled to release its next report next month.
The Nongovernmental International Panel on Climate Change, or NIPCC, which produced the report, is described as "an international panel of scientists and scholars who came together to understand the causes and consequences of climate change." Unlike the "United Nations’ Intergovernmental Panel on Climate Change (IPCC), which is government-sponsored, politically motivated, and predisposed to believing that climate change is a problem in need of a U.N. solution," NIPCC "has no formal attachment to or sponsorship from any government or governmental agency" and is "wholly independent of political pressures and influences and therefore is not predisposed to produce politically motivated conclusions or policy recommendations."
In Climate Change Reconsidered II: Physical Science, which The Heartland Institute published and released on Tuesday, lead authors Craig D. Idso, Robert M. Carter, and S. Fred Singer worked with a team of scientists to produce a 1,200-page report that is "comprehensive, objective, and faithful to the scientific method." They found that even "if the concentration of atmospheric carbon dioxide were to double," whatever "warming may occur would likely be modest and cause no net harm to the global environment or to human well-being."
Breitbart News obtained a detailed summary of the report's key findings. The report rebuts the alarmist reports put out by the United Nations' IPCC, which the authors claim are in "contradiction of the scientific method" because the IPCC assumes that its implicit hypothesis that "dangerous global warming is resulting, or will result, from human-related greenhouse gas emissions" is correct and "that its only duty is to collect evidence and make plausible arguments in the hypothesis’s favor.
According to the study's authors, "the hypothesis of human-caused global warming comes up short not merely of 'full scientific certainty' but of reasonable certainty or even plausibility. The weight of evidence now leans heavily against the theory."
The U.N.'s IPCC's first key claim is that "a doubling of atmospheric CO2 would cause warming between 3°C and 6°C." The study's authors, though, conclude that the "IPCC ignores mounting evidence that climate sensitivity to CO2 is much lower than its models assume." The NIPCC study discovered that warming actually "ceased around the end of the twentieth century and was followed (since 1997) by 16 years of stable temperature."
The IPCC also claims in its reports that "CO2 caused an atmospheric warming of at least 0.3°C over the past 15 years." The lead authors of the report, though, found that the IPCC used incomplete climate models in their research. In fact, the NIPCC's authors found that "no excess warming has been demonstrated."
The IPCC also asserts that a "thermal hot spot should exist in the upper troposphere in tropical regions" even though "observations from both weather balloon radiosondes and satellite MSU sensors show the opposite." Furthermore, the IPCC also asserts that "both polar regions should have warmed faster than the rest of Earth during the late twentieth century" when, in fact, "the large polar East Antarctic Ice Sheet has been cooling since at least the 1950s."
The authors write that the United Nations panel has made "climate change into a political issue long before the science was sufficiently advanced to inform policymakers" and that "most government signatories to the UN’s Framework Convention on Climate Change have deferred to the monopoly advice of the IPCC in setting their national climate change policies."
"More than 20 years down the track, it is now evident this approach has been mistaken," they write. "One result has been the expenditure of hundreds of billions of dollars implementing energy policies that now appear to have been unnecessary, or at least ill-timed and ineffective."
NIPCC's findings "point toward several policy recommendations quite different from those that have come from the IPCC and its related agencies, bureaus, and commissions at the United Nations," and they include: taking into account "long-term trends" in climate science; seeking out advice from "independent, nongovernment organizations and scientists who are free of financial and political conflicts of interest"; allowing individual nations to "take charge of setting their own climate policies based upon the hazards that apply to their particular geography, geology, weather, and culture"; and recognizing "the theoretical hazard of dangerous human-caused global warming is but one small part of a much wider climate hazard," which is as much a "geological as it is a meteorological issue."
The study's authors conclude that "atmospheric carbon dioxide (CO2) is a mild greenhouse gas that exerts a diminishing warming effect as its concentration increases" and even "doubling the concentration of atmospheric CO2 from its pre-industrial level, in the absence of other forcings and feedbacks, would likely cause a warming of ~0.3 to 1.1°C, almost 50% of which must already have occurred." Further, the study found that "a few tenths of a degree of additional warming, should it occur, would not represent a climate crisis" because, over recent geological time, the earth's "temperature has fluctuated naturally between about +4°C and -6°C with respect to twentieth century temperature. A warming of 2°C above today, should it occur, falls within the bounds of natural variability."
Even if a future warming of 2°C occurs, the authors observe that though it "would cause geographically varied ecological responses, no evidence exists that those changes would be net harmful to the global environment or to human well-being" because the "current level of ~400 ppm" proves that "we still live in a CO2-starved world. Atmospheric levels 15 times greater existed during the Cambrian Period (about 550 million years ago) without known adverse effects."
In addition, the earth "has not warmed significantly for the past 16 years despite an 8% increase in atmospheric CO2, which represents 34% of all extra CO2 added to the atmosphere since the start of the industrial revolution."
The U.N.'s IPCC continues, though, to postulate that "increases in atmospheric CO2 precede, and then force, parallel increases in temperature"; "solar forcings are too small to explain twentieth century warming"; and "a future warming of 2°C or more would be net harmful to the biosphere and human well-being." And the IPCC cites circumstantial evidence to support its global warming alarmism. Such evidence include an "unusual melting" that is occurring in mountain glaciers, Arctic sea ice, and polar icecaps," rising global sea levels, an increase in "droughts, floods, and monsoon variability and intensity," more intense "wildfires, rainfall, storms, hurricanes, and other extreme weather events," and an "unusual melting of Boreal permafrost or sub-seabed gas hydrates is causing warming due to methane release."
The report dismisses these claims with peer-reviewed evidence and concludes that "neither the rate nor the magnitude of the reported late twentieth century surface warming (1979–2000) lay outside normal natural variability," "solar forcings of temperature change are likely more important than is currently recognized, and evidence is lacking that a 2° C increase in temperature (of whatever cause) would be globally harmful."
"We conclude no unambiguous evidence exists for adverse changes to the global environment caused by human-related CO2 emissions," the authors write. "In particular, the cryosphere is not melting at an enhanced rate; sea-level rise is not accelerating; no systematic changes have been documented in evaporation or rainfall or in the magnitude or intensity of extreme meteorological events; and an increased release of methane into the atmosphere from permafrost or sub-seabed gas hydrates is unlikely."
The authors also note that "forward projections of solar cyclicity imply the next few decades may be marked by global cooling rather than warming, despite continuing CO2 emissions" and warn against using imperfect deterministic climate models to advocate for a "one size fits all" climate policy.
In light of these findings, which are "stated plainly and repeated in thousands of articles in the peer-reviewed literature" that are not "fringe," the authors emphasize that policymakers "should resist pressure from lobby groups to silence scientists who question the authority of the IPCC to claim to speak for 'climate science.'"