
A new Intergovernmental Panel on Cliamte Change special report reviews estimated global warming trends to date and scenarios in which warming could be limited to 1.5 degrees Celsius.
(Image credit – IPCC, Global Warming of 1.5 °C)
On Oct. 8, the Intergovernmental Panel on Climate Change (IPCC) released a special report
The Trump administration’s response to the report has been muted, consistent with its ambivalent posture toward climate change. While the administration has moved decisively to unwind the Obama administration’s policies to reduce carbon emissions, it has generally refrained from attacking the climate science underlying those policies, defying early expectations
A new Intergovernmental Panel on Cliamte Change special report reviews estimated global warming trends to date and scenarios in which warming could be limited to 1.5 degrees Celsius.
(Image credit – IPCC, Global Warming of 1.5 °C)
The IPCC produced the report to inform policymaking in the wake of the Paris Agreement and to lay groundwork for its next comprehensive climate assessment
The report concludes that keeping average global temperatures within 1.5 degrees of pre-industrial levels will require anthropogenic carbon dioxide emissions to decline about 45 percent from 2010 levels by 2030. By 2050, any further emissions would have to be offset by removing an equal amount of carbon dioxide from the atmosphere.
The report observes such rapid decarbonization would require nations to take steps “unprecedented in terms of scale, but not necessarily in terms of speed” to transform their energy sources, industrial production, land use, and infrastructure. It did not consider the potential alteration of the atmosphere to reduce the warming effects of solar radiation, citing the uncertainties, risks, and social, institutional, and ethical constraints associated with such measures.
The report stresses there will be serious additional consequences if the 1.5 degree limit is exceeded even modestly. With 2 degrees of warming, the report states, sea level rise, the disruption of natural ecosystems, and heightened risks to food and water supplies will cause significantly worse problems across more regions and adaptation will become much more difficult.
While the report presents a grave depiction of the future, some climate scientists contend
The pathways detailed in the IPCC report stand in stark contrast with Trump administration policies, which have prioritized deregulation over emissions reduction.
The administration has already declared its intent to withdraw from the Paris Agreement and to replace a centerpiece of the Obama administration’s climate policy, the Environmental Protection Agency’s Clean Power Plan, with a less stringent regulation
In addition, as part of its budget-cutting agenda, the administration has sought to significantly scale back
Despite its disinterest in tackling climate change, the administration has not sought to challenge the new report. Asked by reporters about it, President Trump indicated he had not yet formed an opinion, remarking
It was given to me. And I want to look at who drew it. … Because I can give you reports that are fabulous and I can give you reports that aren’t so good. But I will be looking at it. Absolutely.
In another statement, an administration spokesperson pointed to U.S. progress to date in reducing carbon dioxide emissions, noting, “From 2005 to 2017, U.S. CO2-related emissions declined by 14 percent while global energy-related CO2 emissions rose by 21 percent during the same time. This has been possible through the development and large-scale deployment of new, affordable, and cleaner technologies to capitalize on our energy abundance.”
European space scientists view NASA data visualizations at the 18th Session of the Conference of the Parties to the UN Framework Convention on Climate Change, held in 2012 in Doha, Qatar.
(Image credit – U.S. State Department)
The administration’s response to the IPCC report is consistent with its general approach to climate science. While it has unsuccessfully sought
Moreover, in advancing its deregulatory goals, the administration has not attempted to undermine the existing scientific consensus on climate change. For example, in working to replace the Clean Power Plan, it has not challenged EPA’s endangerment finding, which established the agency’s legal basis for regulating greenhouse gases based on their effects on public health. In another recent case, a draft environmental impact statement produced by the National Highway Transit Safety Administration specifically cited
Perhaps the clearest sign the administration has taken a deliberately hands-off posture is that the White House reportedly
However, if the administration has an official position on climate science, it has not been forthcoming about it. More clarity could come when the Senate confirms Trump’s nomination of University of Oklahoma meteorologist Kelvin Droegemeier to direct the White House Office of Science and Technology Policy.
The selection
Droegemeier’s own thinking on the subject is ambiguous, as he has only infrequently discussed it in public settings, and generally not in detail. A presentation
The IPCC, it really doesn’t assess the results in the context of policy, it just tells a story. They use very, very careful wording: here’s what we think’s going to happen, here’s the range of uncertainty, so on and so forth.
An “intellectually honest” approach to climate science, he continued, would be to accept that “the observations show the planet is warming, the evidence of the models suggest that it’s human induced or there’s a strong human signal, but we don’t know everything there is to know about the nitrogen cycle, about all the carbon cycling, ... carbon sequestration.” He said the limitations of climate models should be acknowledged and asserted that “unfortunately” many in the scientific community are hostile to discussion of such uncertainties and limitations.
Offering his own perspective on the climate problem, Droegemeier remarked that“the atmosphere is incredibly resilient,” and that “the planet, you can kick it in the butt really, really hard and it will come back. Is there a tipping point for climate change? I don’t know.”
At Droegemeier’s confirmation hearing
Sen. Tom Udall (D-NM) asked Droegemeier what actions he would take at OSTP with respect to climate change. Droegemeier replied he would like to see improved climate modeling, a closer integration of climate and weather research, and continued risk and resiliency planning. He did not mention mitigation.
Contacted for additional elaboration on his climate views, Droegemeier replied he is currently unable to offer comment owing to his pending confirmation.