U.S. Government Climate Science vs. U. S. Government Climate Crisis

­­­­­­Statement for the Record House Committee on Natural Resources

Hearing on: When Science Gets Trumped: Scientific Integrity at the Department of Interior July 25, 2019

Dr. Caleb Stewart Rossiter Executive Director, CO2 Coalition

The scientific integrity of the Department of Interior suffered badly in 2018. As a participating agency in the U.S. Global Change Research Program it approved the publication of Volume II of the fourth National Climate Assessment. Volume II, titled Impact, Risks, and Adaptation in the United States, repeatedly contradicts Volume I, Climate Science Special Report, which was published the year before. Volume I found, as did the latest synthesis report (AR5) by a similar body of government scientists at the UN, in which the United States is a member, that there is no statistically significant evidence that human-caused warming, or in nearly all cases even warming from natural causes, has resulted in an increase in the decadal rates of hurricanes, droughts, floods, storms, precipitation, wildfires, and sea-level rise. Variable periods of extreme weather are not the same as a change in the underlying climate. Volume II, in contrast, repeatedly claims that there have been increases in all of these variables, and many others, because of human-caused climate change. It presents no statistical proof for these claims. It also uses small regions and inappropriately short time periods for analysis that hide its own data and conclusions from appropriate time periods in Volume I. Volume II also presents individual and regional examples of crises as being caused by ‘climate change,’ while Volume I and UN data and conclusions show no trends that allow such attribution. It also repeatedly reports modeled ‘expectations’ and ‘projections’  of extreme and dangerous weather despite the lack of trends to date. Volume II justifies this narrative of the future by claiming that: ‘Climate models have proved remarkably accurate .… Today, the largest uncertainty in projecting future climate conditions is the level of greenhouse gas emissions going forward.’ This is a gross misrepresentation of the state of climate modeling, as described in the UN report. Climate models are mathematical exercises in curve-fitting in which thousands of parameters are tuned to enhance the contribution of carbon dioxide to warming. As a result they have been poor at projections, consistently running two to three times too hot over the past 30 years. It is scientific malfeasance to ignore or misrepresent your own data and conclusions. Volume II is a false narrative, not a work of science, and indeed deserves the label ‘fake science.’ I encourage the Committee to use its oversight functions to find out how this breakdown of scientific principles occurred at the Department of Interior and indeed in the entire U.S. Global Change Research Program.

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From its cover showing a wildfire burning in California to the last of its 1,515 pages, Volume II claims incessantly, in contradiction to Volume I and the UN, that human-caused climate change is creating crises in extreme weather. A single page, provided here here, from Volume II’s Overview compiles many of these false claims. It fundamentally confuses weather with climate by presenting particular examples of extreme weather as “climate change,” despite the Volume I and UN data and conclusions showing no statistically-significant trends for the variables in question. This page is labeled ‘Americans Respond to the Impact of Climate Change.’ From the many claims in Volume II that reducing CO2 emissions will reduce the impact of climate change, it is clear that it is referring here to human-caused climate change. However, this page never tells the reader that the UN has concluded that at least the first half-degree of the past century’s one-degree warming, until 1950, was largely natural because there was insufficient CO2 to force temperature. After 1950, during the era of significant CO2 emissions from the surge in global industrialization, the UN concludes that up to half of the second half-degree of the warming still may be natural. Here is a list of the page’s claims that are contradicted by the data and conclusions in Volume I, and by the UN body. CLAIM: Northwest: Wildfire increases and associated smoke are affecting human health, water resources, timber production, fish and wildlife, and recreation. FACT: Wildfires have increased since 1970, largely because of forest management practices. Volume I says: “(L)ow to medium confidence for a detectable human climate change contribution in the western United States based on existing studies …. The frequency of large wildfires is influenced by a complex combination of natural and human factors. Temperature, soil moisture, relative humidity, wind speed, and vegetation (fuel density) are important aspects of the relationship between fire frequency and ecosystems …. Forest management practices have resulted in higher fuel densities in most U.S. forests …. Recent literature does not contain a complete robust detection and attribution analysis of forest fires including estimates of natural decadal and multidecadal variability…nor separate the contributions to observed trends from climate change and forest management.” CLAIM: Southwest: Drought in the Colorado River Basin has reduced Lake Mead by over half since 2000, increasing risk of water shortages for cities, farms, and ecosystems. FACT: Both Volume I and the UN report no significant trends in drought, and so of course did not conclude that droughts were caused by a temperature increase, natural or man-made. Volume I: “(There is) evidence from paleoclimate proxies of cases of central U.S. droughts during the past 1,000 years that were longer and more intense than historical U.S. droughts. UN: We conclude that there is low confidence in detection and attribution of changes in drought over global land areas since the mid-20th century .… Recent long-term droughts in western North America cannot definitively be shown to lie outside the very large envelope of  natural precipitation variability in this region.” CLAIM: Northern Great Plains: Flash drought and extreme heat illustrate sustainability challenges for ranching operations with emerging impacts on rural prosperity and mental health. FACT: Again, no Volume I or UN trends on drought in the CO2 era. On heat waves, the UN says: “There is also evidence in some regions that periods prior to the 1950s had more heatwaves (e.g., over the USA, the decade of the 1930s stands out and is also associated with extreme drought).” However, the UN was unable to make a global conclusion on whether heat waves have increased, due to a lack of data coverage, but is a weak 66 percent sure that “the frequency of heat waves has increased in large parts of Europe, Asia and Australia.” In any event, how big is the effect, based on all available global data? Tiny. The study the UN relies on says that there has been an increase since 1950 of just one quarter of one percent in the number of heat waves per year, and a 1.4 percent increase in the total number of heat wave days per year.  https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2012GL053361 CLAIM: Southern Great Plains: Hurricane Harvey’s landfall on the Texas coast in 2017 was one of the costliest natural disasters in U.S. history. FACT: If it was a “natural disaster” what is a hurricane doing on a page of “impacts of climate change?” And Volume I and the UN do not find that hurricanes are man-made or part of a trend. Volume 1: “(T)here is still low confidence that any reported long-term (multidecadal to centennial) increases in tropical cyclone (note: includes hurricanes) activity are robust. UN: Current data sets indicate no significant observed trends in global tropical cyclone frequency over the past century …. No robust trends in annual numbers of tropical storms, hurricanes and major hurricanes counts have been identified over the past 100 years in the North Atlantic basin.” CLAIM: Flooding in Louisiana is increasing from extreme rainfall. FACT: Volume I: “Analysis of 200 U.S. stream gauges indicates areas of both increasing and decreasing flooding magnitude but does not provide robust evidence that these trends are attributable to human influences.” UN: “(T)here continues to be a lack of evidence and thus low confidence regarding the sign of trend in the magnitude and/or frequency of floods on a global scale.” (Rossiter note: ‘sign of trend’ means we don’t even know if it is increasing or decreasing.) CLAIM: Midwest: Increasing heavy rains are leading to more soil erosion and nutrient loss on Midwest croplands. FACT: There is a trend to heavy rainfall in parts of the United States, although it has not been attributed to human activities. Globally, there is strong regional variation in heavy rains. Volume I: “Heavy precipitation events in most parts of the United States have increased in both intensity and frequency since 1900 (high confidence). There are important regional differences in trends, with the largest increases occurring in the northeastern United States (high confidence). (Rossiter note: the period from 1901 to today includes half a century of natural warming.) However, trends … identified for the U.S. regions have not been clearly attributed to anthropogenic forcing.” UN: “It is likely that since 1951 there have been statistically significant increases in the number of heavy precipitation events in more regions than there have been statistically significant decreases, but there are strong regional and subregional variations.” CLAIM: U.S. Caribbean Damages from the 2017 hurricanes have been compounded by the slow recovery of energy… FACT: As above, no hurricane trends. CLAIM: Northeast: Water, energy and transportation are affected by snowstorms, drought, heat waves, and flooding. FACT: No significant national or global trends, whether man-made or natural, have been identified for these variables. Drought, heat waves, and flooding have been covered above. On snowstorms, Volume I finds regional variation but no national trend:  “Changes in snow cover extent (SCE) in the Northern Hemisphere exhibit a strong seasonal dependence. There has been little change in winter SCE since the 1960s (when the first satellite records became available), while fall SCE has increased. However, the decline in spring SCE is larger than the increase in fall…”

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