Responding to the National Climate Assessment Report

When paleontologist Stephen Jay Gould heard from his doctor that he had a rare and serious stomach cancer, he went straight to the medical library and devoured the scientific literature on his condition. He tells this story in his essay The Median Isn’t the Message.  “The literature,”  he writes, “couldn’t have been more brutally clear: mesothelioma is incurable, with a median mortality of only eight months after discovery.” The prognosis, the science, and the statistics helped Gould understand the nature of the disease, but after sitting in shock with the information, his realized that the most statistically likely life expectancy wasn’t up to chance alone.  Attitude, he recognized, matters mightily in living with cancer.  Three years later, he wrote about reckoning with the knowledge of having mesothelioma, and lived twenty years longer.

On Black Friday, the U.S. Global Climate Change Research Program released its congressionally mandated fourth national climate assessment report to update the public and lawmakers with information about the evidence and risks of climate change. This report, reviewed by the UW Program on Climate Change, builds off of previous reports, with more evidence of warming, regional impacts, and details for the public and policy makers. The core science, that human emissions of greenhouse gasses are disrupting ecosystems, agriculture, human health and economies around the world, has been established in the scientific community for decades. This report makes clear that harmful impacts of climate change are occurring already in the U.S.

What does the report say specifically for the Pacific Northwest?


Increased temperatures and reduced winter snowpack raise the likelihood of more frequent droughts,  wildfires, infectious diseases, and other health impacts. The report uses recent wildfires and extreme heat events as case studies for how human health, infrastructure, and the economy is impacted by these climate-sensitive events, as rising temperatures will increase their frequency and intensity in the future.

Workers fight mountain pine beetles with pesticides. Rising temperatures make forests more susceptible to such pests. Photo credit:

For example: the Goodell wildfire in August 2015 forced Seattle City Light to de-energize transmission lines around its Skagit River Hydroelectric Project for several days. The combined impact of damages and lost power production totaled nearly $3 million (in 2015 dollars).

In Washington, the Department of Ecology allocated almost $7 million in drought relief funds in 2015 (in 2015 dollars). Relief grants were used to provide backup or emergency water supplies for irrigation or human consumption where wells were failing or pumping capacity was inadequate. Typically small or rural water supply systems are relatively more vulnerable to drought impacts when compared to larger urban systems.

In the last several years, our region has seen an increase in some infectious diseases including Lyme disease, associated with rising temperatures and changing tick habitat.

The Washington Department of Health’s vector surveillance program observed an earlier onset of West Nile virus-carrying mosquitoes, and an increasing number of human infections, with some resulting in fatalities.  Before 1999, cryptococcal infections were limited to the tropics, but Cryptococcus gatti, the species that causes these infections, is now established in Northwest soil, leading to 76 West Nile cases occurring in Oregon in 2015.  The Oregon Health Authority recorded spikes in cases of Salmonella and E. coli during months with extreme heat in 2015. A large outbreak of Shigellosis (a bacterial diarrheal disease) occurred in late 2015, affecting a large number of homeless people in the Portland Metro region; this outbreak was associated with unusually extreme precipitation.

Communities with higher rates of illness and death often have less adaptive capacity and are more vulnerable to climate stressors. Many people living in the Northwest already struggle to meet basic needs which, if met, could serve as protective factors. People lacking adequate shelter face increased climate risks (such as direct exposure to extreme heat or winter storms), while also having increased vulnerability (such as poorer health and less access to resources).

Children and youth, in general, will likely experience cumulative physical and mental health effects of climate change over their lifetimes due to increased exposure to extreme weather events such as heat stress, trauma from injury, or displacement and increased toxic exposures such as increased ground-level ozone pollution in urban areas or increased risk of drinking water contamination in rural areas. Infants and children can be disproportionately affected by toxic exposures because they eat, drink, and breathe more in proportion to their body size.


The intent of the report is to inform, but not to prescribe, decisions. And yet people often ask, “what can I do with this distressing information?” Here too, our response to this information matters mightily. One helpful response is simply to talk about climate change more frequently.

The Yale Climate Opinion maps show that, in Washington State:

  • 6/10 Washingtonians think global warming will NOT harm them personally
  • 6/10 Washingtonians never discuss global warming
  • 7/10 Washingtonians hear about global warming in the media less than once per week

As we spend more time indoors during this cold damp winter season, we encourage you to bring climate change into everyday conversations with friends or family. The acclaimed atmospheric scientist and 2018 UW Fleagle Distinguished Fellow Dr. Katherine Hayhoe offers easy-to-follow advice on how to have better climate conversations.

To take it one step further, host discussions with community groups about climate change, and how it concerns you. You can request a scientist from the Program on Climate Change to come speak with your civic/community/educational group on topics of special concern.

Science informs, but it’s up to all of us — society at large— to use the evidence and act courageously to create the future we want. The biggest uncertainty in climate predictions is how humankind will respond to the knowledge of this growing crisis, and how quickly we transition from fossil fuels to a clean energy economy.

by Judy Twedt, Doctoral Candidate, Interdisciplinary PhD Program and Cecilia Bitz, Director, UW Program on Climate Change and Professor, UW Atmospheric Sciences