For Immediate Release, May 6, 2014

Contact: Patrick Sullivan, (415) 517-9364,

National Climate Report Finds Huge Flood Threat to Major U.S. Coastal Cities

Scientists Also Warn of Food Supply Threat, More Destructive Hurricanes,
Up to 10 Degrees of Warming This Century

SAN FRANCISCO— Climate change has dangerously increased flood risk in many of America’s largest coastal cities and will drive up sea levels as much as 4 feet by 2100, according to a new federal report released today.

The National Climate Assessment also predicts serious climate threats to America’s food supply, an increased risk of powerful hurricanes, and as much as 10 degrees Fahrenheit of warming by the end of the century unless deep cuts are made to carbon pollution. More than 300 experts were involved in creating this scientific report.

"This is more than just the scientific case for action on climate change,” said Shaye Wolf, the Center’s climate science director. “There's no doubt that human lives are at risk and human misery will be the price of inaction. President Obama has a moral obligation to act, not just in a series of small steps but in ways that will finally begin turning the tide of this global crisis."

Here are the five most disturbing findings of the National Climate Assessment:

  1. Rising seas and more damaging extreme weather: New York, Boston, Miami, New Orleans, the San Francisco Bay area and many other coastal cities are threatened by flooding and seawater intrusion because of sea-level rise. Sea levels could rise 4 feet by 2100, imperiling communities and critical infrastructure, as well as key wildlife habitat. Storm surges will become more destructive because they will ride on higher sea levels.
  2. More extreme heat: America will warm by as much as 10 degrees Fahrenheit by 2100 if carbon emissions keep rising, the report says. Major heat waves have become more intense and more common.
  3. Endangered food supply: Food insecurity will increase in America and around the world, the report says. Yields of major U.S. crops are expected to decline by 2050 because of rising temperatures and growing precipitation extremes. Fishing and other marine-based food production will also suffer because ocean waters are becoming warmer and more acidic.
  4. Biodiversity threatened: Many plants and animals and their habitats may be overwhelmed by climate change and other stressors. Climate change is altering some ecosystems so rapidly, the report finds, that many species “may disappear from regions where they have been prevalent or become extinct, altering some regions so much that their mix of plant and animal life will become almost unrecognizable.”
  5. Carbon emissions rising rapidly: Carbon pollution is still increasing, with global emissions “on a path to be even higher than the high emissions scenario” analyzed in the report. America’s contribution to global emissions is about 20 percent, and our efforts to reduce pollution are too slight to comply with international agreements to avoid dangerous climate change.

Deep and rapid greenhouse gas cuts are needed to reduce these risks. The Clean Air Act is America’s leading tool for curbing greenhouse gas pollution, and 79 U.S. cities have joined the Center’s Clean Air Cities campaign urging the EPA to use the Clean Air Act to help reduce carbon in our atmosphere to no more than 350 parts per million, the level scientists say is needed to avoid catastrophic climate change. 

The Center for Biological Diversity is a national, nonprofit conservation organization with more than 775,000 members and online activists dedicated to the protection of endangered species and wild places.

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