Pacific Southwest, Region 9
Serving: Arizona, California, Hawaii, Nevada, Pacific Islands, Tribal Nations
Climate Change in the Pacific Southwest
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Just as the ecosystems in the Pacific Southwest Region are extremely diverse, so are the impacts of climate change. Many environmental impacts are already apparent, including increased forest fires and droughts, threatened or extinct animal and plant species, sea level rise and coral bleaching from ocean acidification. Below are some examples of documented changes resulting from global warming in our region. Information on national and international impacts of climate change is also available on EPA's national Web site.
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Resurveying the Wildlife of California and Nevada
Nearly a century ago, Joseph Grinnell started a project with his colleagues and students to document the wildlife of California. They surveyed over 700 locations in California and Nevada, documenting and collecting mammals, birds, reptiles and amphibians. Today, the UC Berkeley Museum of Vertebrate Zoology is resurveying these locations to get a comprehensive dataset on how ecology in California has changed.
Butterflies in Danger
The Bay Checkerspot butterfly is both federally listed as threatened, and now extinct on most of the San Francisco peninsula including nature preserve Jasper Ridge in California. A study by a group of scientists shows that this extinction was likely hastened by increased variability in climate which is likely caused by climate change.
Hawaiian Honeycreepers Face Extinction
Several scientists look into human impacts on Honeycreeper birds in Hawaii. Landscape analyses of three high-elevation forest refuges shed light on a deadly combination of anthropogenic climate change, past land-use changes and biological invasions. These combined forces threaten to drive several of the remaining species to extinction, especially on the islands of Kauai and Hawaii.
Ocean Acidification, Sea Level Rise, Polluted Seas and More
A recent study indicates that increased ocean absorption of carbon dioxide is impacting the calcification of shellfish and could threaten the entire ocean ecosystem. EPA is soliciting information that may be used to develop guidance on how to address ocean acidification. The Center for Ocean Solutions is a collaborative effort funded by the Packard Foundation and drawing upon the resources of Stanford University, the Monterey Bay Aquarium, and the Monterey Bay Aquarium Research Institution. This report reviews more than 3,400 scientific papers to outline the major threats to the Pacific Ocean.
Air Quality Impacts
EPA Region 9 has funded several research projects to examine the impact of climate change on air quality, specifically examining the impacts on criteria pollutants as identified under the Clean Air Act.
Assessing the consequences of Global Change for Air Quality: Sensitivity of U.S. Air Quality to Climate Change and Future Global Impacts
The overall objective of this project is to assess the impact of changes in regional and global climate on air quality in California. By using a combination of model and observation-based analyses, they determine the effects on air quality of changes in temperature, moisture, pollutant inflows from the Pacific Ocean, and future changes in emissions in central California.
Regional Development, Population Trend, and Technology Change Impacts on Future Air Pollution Emissions
The purpose of this study is to integrate economic forecasts with land-use models, water constraint models, travel demand models, and stationary source models to create an emissions modeling system that can be used to predict future air pollution emissions. The new emissions modeling system will be demonstrated by predicting air quality emissions in the San Joaquin Valley in central California during the year 2030.
Consequences of Global Change For Air Quality
Ozone and particulate matter standards designed to protect public health are routinely violated in California’s south coast air basin surrounding Los Angeles and the San Joaquin Valley in central California. Global change will affect air quality in California through adoption of new technology, altered background concentrations, and evolving meteorological conditions. The magnitude and direction of these effects are unknown, and so the true public health costs of global change can not be quantified at this time.
Climate Data Shows California Has Been Heating Up
Bill Patzert of NASA's Jet Propulsion Laboratory, Pasadena, Calif., teamed with Steve LaDochy of California State University, Los Angeles, and Richard Medina, now a doctoral candidate at the University of Utah, Salt Lake City, to investigate California air temperature patterns from 1950 to 2000. Average temperatures increased significantly in nearly 54% of the stations studied, with human-produced changes in land use seen as the most likely cause.
Increased Forest Fires in Western U.S.
Scientists from universities in California and Arizona as well as the United States Geological Service collaborate to look at a comprehensive data set of forest fires in since 1970 to determine what is driving the recent increase in the frequency and areas burned by forest fires. Their study indicates that the increase may be caused by land management practices or increased climatic variability associated with climate change. Improvements in agriculture and forestry practices can reduce carbon emissions as well as increase carbon sequestration.