At 1,656 pages, National Climate Assessment (NCA) prepared by the U.S. Global Change Research Program (USGCRP) provides a grim look on the impact that climate change will have on the United States. The Global Change Research Act of 1990 mandates the preparation of a report no less than every four years to interpret the findings of the USGCRP; analyze the effects of global change; and analyze the current trends in global change and projections for trends 20 to 50 years in the future. NCA 4 was released in two volumes. Volume I, the Climate Science Special Report, was released in 2017. That report looked at how climate change is affecting the earth system throughout the United States and provided the foundational science used in Volume II. Volume II was prepared by more than 300 federal and non-federal experts and reviewed by external experts, the general public, and the NCA4 Federal Steering Committee. Volume II was released seemingly under the cover of the Thanksgiving holiday and Black Friday, since it fails to coincide with the current administration’s views on climate change.
Volume II is entitled, Impacts, Risks, and Adaptations in the United States. There are 12 broad findings from the report, which help paint a picture of a country that will struggle in the face of climate change. The report notes that communities are already feeling the impacts of climate change, but that this will only increase over time. There will be more frequent and more extreme weather and climate-related events that will continue to damage the structures and systems of communities. A significant cut in greenhouse gas emissions could substantially reduce these risks. The report notes that although there have been increased mitigation and adaptation efforts over the past four years, the efforts are not on a great enough scale to avoid substantial damages to the economy, environment, and human health in the coming decades. This is much in line with the IPCC report released last month.
The impact and risk on the economy seemed to be a real eye opener for many. Without significant adaptation changes across the globe, rising sea level, temperatures, and extreme weather events will damage critical infrastructure and labor; increase the cost of electricity by making its generation less efficient; affect import and export prices due to supply chain problems; and result in the loss of hundreds of billions of dollars by the end of the century. Aging infrastructure, changes in land use based on the changing climate, and increased global populations will result in critical impacts on water and food systems, energy, transportation, trade, and national security. These interconnected impacts which affect the United States and the entire world could be greater than any individual impacts.
Parts of the United States will have scarce availability of water. There is groundwater and surface water depletion from less snowpack and intensified drought in regions of the country. This not only affects the domestic supply of water, but also the reliability of renewable energy through hydropower and cooling for power plants. There needs to be greater water management throughout the country, but such management has been scarcely implemented. Somewhat related to the water issue is the increase in health related dangers caused by air pollution from wildfires. Wildfires have increased in duration and intensity. Climate change will also have other health related impacts by increasing the geographic range of disease carrying insects and pests. Already, ticks and mosquitoes carrying Lyme disease, Zika, West Nile virus, and dengue fever have expanded into areas previously unaffected by such diseases. Indigenous communities who live off the land will have greater problems doing so as a result of climate change, which may lead to relocation. Agricultural productivity in the United States will decrease due to livestock illness, declining crop yields, declining crop quality, soil erosion, and pest infestation.
The nation’s infrastructure, which is already crumbling in many places from neglect, will only be further decimated by extreme flooding, coastal erosion, heat, and wildfires. Coastal communities will be greatly impacted by the loss of land through erosion, loss of fisheries, and sea level rise. Outdoor recreation and tourism will also be impacted by climate change. Loss of snowpack and snow impacts ski and other winter recreation industries. Coastal erosion and the increase in red tide or other algae blooms negatively affects beaches and other summer recreation spots. Wildfires close national parks and other areas of scenic beauty. Animal migration and species loss can impact many different industries.
The ultimate takeaway from the report is that the climate is changing faster than it ever has before. Impacts from this change are already being felt throughout the United States and will only become worse over the coming years. It is necessary to take action today to prevent the increased impact from global climate change. Although some steps have been taken, these steps are not enough to combat the changes to come and more drastic action is needed. There needs to be a greater reduction in greenhouse gas emissions as well as regional adaptation measures.