This report is a new very comprehensive scientific report on Climate Change that has been formally approved by the scientific community and now awaits approval from the Trump administration before it can be formally issued. To be a tad more specific, the heads of the various federal agencies need to sign it off by 18th August.
When I use the word “comprehensive” to describe it, I’m really not kidding, it runs to over 669 pages. It is part of the National Climate Assessment, and has been mandated by Congress for issuance every four year. This is the definitive authoritative assessment of the science of climate change right now, and has a specific US focus. If you keep you finger on the climate change pulse then it contains nothing new, but instead gathers together all the latest information.
It contains …
- An updated detailed analysis of the findings of how climate change is affecting weather and climate across the United States
- An executive summary
- Foundational information and projections for climate change
If you do wade into it, then be aware that most of it is written at a level more appropriate for a scientific audience. However, the Executive Summary is quite readable to most people.
So what happens now, will it cross the last hurdle and get signed off?
Let’s park that question for a moment and first dig into the details of the report itself.
Who wrote it?
Scientists from over 13 federal agencies have been involved. Many subject matter experts have contributed, so the best I can do it to perhaps list some of the lead authors and their affiliations so that you can grasp the scope of the expertise that has been deployed here …
- Jeff Arnold, U.S. Army Corps of Engineers
- Benjamin DeAngelo, U.S. Global Change Research Program
- Sarah Doherty, University of Washington
- David Easterling, NOAA National Centers for Environmental Information
- James Edmonds, Pacific Northwest National Laboratory
- Timothy Hall, NASA Goddard Institute for Space Studies
- Katharine Hayhoe, Texas Tech University
- Forrest Hoffman, Oak Ridge National Laboratory
- Radley Horton, Columbia University
- Deborah Huntzinger, Northern Arizona University
- Libby Jewett, NOAA Ocean Acidification Program
- Thomas Knutson, NOAA Geophysical Fluid Dynamics Lab
- Robert Kopp, Rutgers University
- James Kossin, NOAA National Centers for Environmental Information
- Kenneth Kunkel, North Carolina State University
- Allegra LeGrande, NASA Goddard Institute for Space Studies
- L. Ruby Leung, Pacific Northwest National Laboratory
- Wieslaw Maslowski, Naval Postgraduate School
- Carl Mears, Remote Sensing Systems
- Judith Perlwitz, NOAA Earth System Research Laboratory
- Anastasia Romanou, Columbia University
- Benjamin Sanderson, National Center for Atmospheric Research
- William Sweet, NOAA National Ocean Service
- Patrick Taylor, NASA Langley Research Center
- Robert Trapp, University of Illinois at Urbana-Champaign
- Russell Vose, NOAA National Centers for Environmental Information
- Duane Waliser, NASA Jet Propulsion Laboratory
- Michael Wehner, Lawrence Berkeley National Laboratory
- Tristram West, DOE Office of Science
What does it tell us?
There is quite frankly a vast amount of tightly packed information within this report that is very robustly evidence based. To give you a quick feel for it, here is a small selection of some key facts from Chapter 1…
The global climate continues to change rapidly compared to the pace of the natural variations in climate that have occurred throughout Earth’s history. Trends in globally averaged temperature, sea level rise, upper-ocean heat content, land-based ice melt, Arctic sea ice, depth of seasonal permafrost thaw, and other climate variables provide consistent evidence of a warming planet. These observed trends are robust and have been confirmed by multiple independent research groups around the world. (Very high confidence)
The frequency and intensity of extreme heat and heavy precipitation events are increasing in most continental regions of the world (very high confidence). These trends are consistent with expected physical responses to a warming climate. Climate model studies are also consistent with these trends, although models tend to underestimate the observed trends, especially for the increase in extreme precipitation events (very high confidence for temperature, high confidence for extreme precipitation). The frequency and intensity of extreme temperature events are virtually certain to increase in the future as global temperature increases (high confidence). Extreme precipitation events will very likely continue to increase in frequency and intensity throughout most of the world (high confidence). Observed and projected trends for some other types of extreme events, such as floods, droughts, and severe storms, have more variable regional characteristics.
Many lines of evidence demonstrate that it is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century. Formal detection and attribution studies for the period 1951 to 2010 find that the observed global mean surface temperature warming lies in the middle of the range of likely human contributions to warming over that same period. We find no convincing evidence that natural variability can account for the amount of global warming observed over the industrial era. For the period extending over the last century, there are no convincing alternative explanations supported by the extent of the observational evidence. Solar output changes and internal variability can only contribute marginally to the observed changes in climate over the last century, and we find no convincing evidence for natural cycles in the observational record that could explain the observed changes in climate. (Very high confidence)
Global climate is projected to continue to change over this century and beyond. The magnitude of climate change beyond the next few decades will depend primarily on the amount of greenhouse (heat-trapping) gases emitted globally and on the remaining uncertainty in the sensitivity of Earth’s climate to those emissions (very high confidence). With significant reductions in the emissions of greenhouse gases, the global annually averaged temperature rise could be limited to 3.6°F (2°C) or less. Without major reductions in these emissions, the increase in annual average global temperatures relative to preindustrial times could reach 9°F (5°C) or more by the end of this century (high confidence).
Natural variability, including El Niño events and other recurring patterns of ocean– atmosphere interactions, impact temperature and precipitation, especially regionally, over months to years. The global influence of natural variability, however, is limited to a small fraction of observed climate trends over decades. (Very high confidence)
Longer-term climate records over past centuries and millennia indicate that average temperatures in recent decades over much of the world have been much higher, and have risen faster during this time period, than at any time in the past 1,700 years or more, the time period for which the global distribution of surface temperatures can be reconstructed. (High confidence)
None of that is perhaps new to you if you already keep up to date on the topic.
Side note: The words in red are terms that are very specifically defined within the report and are not vague but instead express a very precise degree of meaning. For example, “Very high confidence” is defined to mean …
What is potentially new is that there is a real fear within the scientific community that this report will be suppressed. The New York Times covers this in detail …
The E.P.A. is one of 13 agencies that must approve the report by Aug. 18. The agency’s administrator, Scott Pruitt, has said he does not believe that carbon dioxide is a primary contributor to global warming.
“It’s a fraught situation,” said Michael Oppenheimer, a professor of geoscience and international affairs at Princeton University who was not involved in the study. “This is the first case in which an analysis of climate change of this scope has come up in the Trump administration, and scientists will be watching very carefully to see how they handle it.
Scientists say they fear that the Trump administration could change or suppress the report. But those who challenge scientific data on human-caused climate change say they are equally worried that the draft report, as well as the larger National Climate Assessment, will be publicly released.
So what happens now?
We simply don’t know how the politics will play out, but with the 18th Aug deadline for signing it off looming we shall soon find out.
The draft of the report has been available for some time for public comment, and so it is available online. Some media stories reported that it had been leaked, but this is not correct, and so the outlet that first issued that claim has corrected it. Others however picked up the leak claim before that correction, hence the “it was leaked” is still floating about out there. As for the report itself, even if it is actually suppressed, it will not be going away.
If I was to speculate what will actually happen, then my best guess here is that all of the agencies will sign and life will go on. Even Scott Pruitt will most probably sign it off. The alternative would be utterly insane and would throw a very public spotlight upon the administration as one that is definitively anti-science, hence I lean towards thinking that they would not be stupid enough to suppress it or interfere with it.
However, when I’ve speculated in the past and leaned towards the most pragmatic and politically sensible being the most probable, then I’ve been proven to be quite wrong. For example I speculated that Trump would simply not be stupid enough to try and pull the US out of the Paris Agreement – so yes, I was really wrong about that call.
That perhaps is sometimes how things do work out. Whenever you think, “Nobody would be that stupid”, up pops somebody to prove you quite wrong. This is a definitive attribute within the political arena that Trump has managed to gain a monopoly of. In the end the politics is utterly irrelevant because reality is not something that politicians can regulate. Either we address the existential crisis we as a species now face or we don’t and so face the consequences.