Officials from twelve states including New York submitted a comment labelled as State Environmental and Energy Regulators’ Comment on Advance Notice of Proposed Rulemaking, Docket ID No. EPA-HQ-OAR-2017-0545 on February 26, 2018. The comments, facilitated by the Georgetown Climate Center, were from: California, Connecticut, Massachusetts, Minnesota, New York, North Carolina, Oregon, Pennsylvania, Rhode Island, Vermont, Virginia, and Washington. The letter discusses the need to reduce emissions of the greenhouse gases that cause climate change and this post reviews their rationale for that need.
EPA requested comments on a proposed rulemaking to revise the Obama-era Clean Power Plan which was a regulation to limit CO2 emissions from power plants. From my pragmatic standpoint the ultimate issue is whether the regulation can actually impact the purported effects better than an alternate response.
The comment starts as follows:
We are environmental and energy regulators from a group of 12 states, and we are providing comment on the Environmental Protection Agency’s (EPA) Advance Notice of Proposed Rulemaking on State Guidelines for Greenhouse Gas Emissions from Existing Sources (ANPRM).
We represent states that are already suffering the economic and human consequences of climate change, and that are leaders in working to reduce the emissions that cause it. Extreme weather events in recent years have continued to cause record damages that disrupt state economies and require years for recovery. For example, in 2017 California experienced almost twice as many wildfires burning six times as many acres as the average over the last five years, and these fires were among the deadliest in the state’s history, killing a total of 47 people. The National Oceanic and Atmospheric Administration (NOAA) estimates that Hurricane Sandy caused damages of over $70 billion, and projected damages from Hurricane Harvey total $125 billion. With over $300 billion in estimated losses from disaster events in 2017, last year was by far the costliest year for climate and weather related events, and it also tied the record for the number of billion-dollar disaster events in a single year. Our states are working to reduce harmful climate pollution individually and jointly. Minnesota’s GDP grew by 23.1 percent between 2000 and 2014, while its emissions decreased by 3.6 percent. North Carolina’s Renewable Energy and Energy Efficiency Portfolio Standard has resulted in investments of over $10 billion in clean energy technologies, created 34,000 clean energy jobs, and reduced CO2 emissions by 14.6 percent between 2004 and 2014. Since the launch of the multi-state Regional Greenhouse Gas Initiative, carbon emissions from power plants in the region have decreased by 40 percent. EPA should act urgently to reduce the risk to American citizens from further climate impacts, and should take into account the methods our states have already proven as effective and affordable in reducing carbon pollution.
My problem with this rationale is that it only lists a series of weather events but does not explain how much of the observed events are the result of climate change and, therefore, could be affected by the control program they support. Ultimately, the alleged effects of human impacts on climate are not creating new weather-related hazards. Climate change could make weather hazards more frequent and more intense but will not prevent them from occurring in the future.
Consider, for example, the statement “projected damages from Hurricane Harvey total $125 billion”. Hurricane Harvey was “A category 4 hurricane (on the Saffir-Simpson Hurricane Wind Scale) before making landfall along the middle Texas coast. The storm then stalled, with its center over or near the Texas coast for four days, dropping historic amounts of rainfall of more than 60 inches over southeastern Texas.” “Harvey was the most significant tropical cyclone rainfall event in United States history, both in scope and peak rainfall amounts, since reliable rainfall records began around the 1880s”. Not surprisingly with this much rain there was catastrophic flooding and the fact that it happened over the major metropolitan area of Houston made it very costly.
The comment letter states “Extreme weather events in recent years have continued to cause record damages that disrupt state economies and require years for recovery” and uses the very large damage estimate as an example. Not addressed was whether climate change affected the rainfall and thus the damage.
In the first place, using damage estimates is a weak argument for climate change affecting Harvey. If the storm had not stalled over Houston there would have been much less to damage and the costs would have been lower. A recent paper makes the point that “Growth in coastal population and regional wealth are the overwhelming drivers of observed increases in hurricane-related damage”. The paper also shows that there has been no significant change since 1900 in hurricanes that land in the United States for frequency or intensity. So the real argument that the state comments should have made is that Hurricane Harvey itself was affected by climate change.
There are a couple of analyses that do claim that Harvey rainfall was affected by climate change. A team of scientists from World Weather Attribution claimed that human-caused climate change made the record rainfall that fell over Houston during Hurricane Harvey roughly “three times more likely and 15 percent more intense”. Another paper suggests that the annual chance of at least 500 mm (20”) of rain over Texas like that seen from Hurricane Harvey would increase from about 1% between 1981-2000 to 18% by the end of the 21st Century and concludes that the risk from a Harvey event has already increase six-fold in 2017 (a 6% chance of occurrence yearly) versus that from just a couple decades ago.
Both of these analyses use output from dynamical weather forecast models to project the effect of climate change. The theory is that a warmer atmosphere can hold more moisture so rainfall rates would be more intense. Landsea references a study that explains “Theory suggests that the amount of rainfall in the tropical latitudes would go up about 4% per deg F sea surface temperature (7% per deg C). Climate models forced by assuming continued emissions of greenhouse gases suggest around 2-2.5 deg F (1-1.5 deg C) warming by the year 2100, or about 10% more tropical rainfall. Landsea then notes:
Scaling the results from both theory as well as climate model projections suggest, then, that roughly 3% of hurricane rainfall today can be reasonably attributed to manmade global warming. This value is a rather tiny contribution. Thus only about 2” (50 mm) of Hurricane Harvey’s peak amount of 60” (1525 mm) can be linked to manmade global warming.
Landsea goes on to explain why he does not consider the other results reliable. I prefer to use all the results to provide a range of potential outcomes
So even if the State comments had properly considered the real effect of climate change on extreme weather events instead of the inappropriate total cost of a storm, there are a legitimate range of potential outcomes – (15% more intense to 3% more intense). These comments do not provide an appropriate rationale why they believe controls are necessary because they did not provide a science-based argument. Instead they have relied on emotion-based claims of damages without attributing them to climate change impacts.
The Landsea paper lists lessons to be learned from Harvey’s catastrophic flooding that summarize the important points that should be recognized that is written so well I want to include it here:
- Hurricanes (and Tropical Storms) have been associated for millenniums with extreme rainfall and freshwater flooding. There is nothing that one can do to prevent these storms from occurring, hitting land, and impacting people;
- Massive flooding and catastrophic impact from tropical storms and hurricanes occurs when the system moves slowly over a major city. This is precisely what happened because of Harvey as a tropical storm over Texas;
- Flooding is made worse when extreme rainfall occurs over impervious land (such as roads and buildings) and the rain cannot soak in. Land use decisions should better consider allowing building (or rebuilding) in flood prone areas;
- Studies should be made to see if evacuating people in advance of extreme flooding rain is feasible. (Currently, only evacuations from hurricanes are primarily issued from possible storm surge – salt-water – flooding. However, because the skill of in day-to-day rainfall amounts and locations continues to improve, it might be feasible to call for limited evacuations in the most vulnerable locations.);
- Linking hurricane rainfall to global warming today (and even decades from now) based upon such a tiny contribution is misleading. Moreover, such a fixation can delay steps that can be taken now to better mitigate the effects of extreme flooding from hurricanes. See the following sites for more action today that can be taken: the Federal Emergency Management Agency (FEMA), the Insurance Institute for Business and Home Safety (IIBHS), the Environmental Protection Agency (EPA), and academia (University of Colorado, University of Pennsylvania, and University of Iowa).
Paraphrasing Dr. Landsea, the fixation on reducing greenhouse gas emissions in the Obama-era Clean Power Plan is delaying actions that could and should be done today to mitigate the inevitable catastrophic hurricane damages. The comment letter by these states continues this inappropriate fixation. Moreover, the comments do not provide any indication how much their preferred control options would impact global warming in general or the alleged impacts listed in particular.
 82 Fed. Reg. 61,507 (Dec. 28, 2017).
 “Incident Information,” California Department of Forestry and Fire Protection, http://cdfdata.fire.ca.gov/incidents/incidents_stats?year=2017.
 California Department of Forestry and Fire Protection, Large Fires 2017: 300 Acres and Greater, http://cdfdata.fire.ca.gov/pub/cdf/images/incidentstatsevents_273.pdf.
 Billion-Dollar Weather and Climate Disasters,” NOAA, https://www.ncdc.noaa.gov/billions/events/NY/1980-2017.
 Devashree Saha & Mark Muro, The Brookings Institution, Growth, Carbon, and Trump: State progress and drift on economic growth and emissions ‘decoupling’ (December 8, 2016), Fig. 3.
 RTI International, Economic Impact Analysis of Clean Energy Development in North Carolina – 2017 Update (Oct. 2017), https://energync.org/wp-content/uploads/2017/10/Summary-Findings_Economic-and-Rate-Impact-Analysis-of-Clean-Energy-Development-in-North-Carolina%E2%80%942017-Update-October-Version.pdf
 U.S. Climate Alliance, 2017 Annual Report, https://static1.squarespace.com/static/5936b0bde4fcb5371d7ebe4c/t/59bc4959bebafb2c44067922/1505511771 219/USCA_Climate_Report-V2A-Online-RGB.PDF.
 North Carolina Utilities Commission, Annual Report Regarding Renewable Energy and Energy Efficiency Portfolio Standard in North Carolina Required Pursuant to G.S. 62-133.8(J) (October 1, 2017), http://www.ncuc.commerce.state.nc.us/reports/repsreport2017.pdf.
 “RGGI Emissions Fell Again in 2016,” Acadia Center (March 10, 2017), http://acadiacenter.org/rggi-emissionsfell-again-in-2016/.