Photograph by David McNew, Getty

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A dog hangs around an abandoned farmhouse in February near Bakersfield, California, during the driest year on record. Scientists warn that such droughts may get worse with climate change.

Photograph by David McNew, Getty

Federal Climate Change Report Highlights Risks for Americans

The National Climate Assessment calls for action on global warming.

The White House released a major report on climate change on Tuesday, warning of global warming-related problems that are already affecting ordinary Americans and calling for more action to reduce greenhouse gas emissions.

"The findings in this National Climate Assessment underscore the need for urgent action to combat the threats from climate change, protect American citizens and communities today, and build a sustainable future for our kids and grandkids," the White House said in a statement.

The assessment represents the most comprehensive review of climate impacts in the U.S. in over a decade, with contributions from 13 federal agencies and more than 300 scientists and experts, as well as input from the business community.

Sierra Club executive director Michael Brune called the report "a wake-up call that we simply cannot afford to sleep through yet again.

"American families are already paying the costs of the extreme weather and health risks fueled by the climate crisis," he said. "The toll on our health, our communities, and our economy will only skyrocket across the country if we do not act."

But some conservative groups reacted with skepticism. The libertarian Cato Institute wrote in a blog post that the report "overly focuses on the supposed negative impacts from climate change while largely dismissing or ignoring the positives from climate change."

Specifically, Cato argued that increasing temperatures decrease people's sensitivity to heat.

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The massive Rim Fire burns near Buck Meadows, California, on August 21, 2013. Such large wildfires will become more likely in many areas because of climate change.

Focus on the Present

The peer-reviewed Third National Climate Assessment argues that climate change is already resulting in substantial financial, public health, and ecological costs, from increasingly severe weather to disruption of infrastructure. The report points to droughts in the West and flood-based damage to roads in the East.

Many steps are being taken to curb emissions and mitigate impacts of climate change, but the new report warns that those actions have been insufficient, particularly at the local level.

For example, coastal communities haven't done enough to protect shorelines from rising seas, while many areas in the Southeast and Southwest aren't well prepared for water shortages, the report says. (Read "Rising Seas" in National Geographic magazine.)

The report provides guidance for local officials across the country on how to respond to climate change. It advises coastal jurisdictions on how to prepare for sea-level rise and Western regions on planning for drought and wildfires.

Eric Pooley, a vice president for strategy and communications with the Environmental Defense Fund, said that President Obama has steadily been following through on a Climate Action Plan he unveiled last June.

That plan aims to set new rules on carbon emissions for new and existing power plants and address methane emissions from the gas industry. But Pooley said the National Climate Assessment proves that plan is "not enough."

The White House, for its part, is promoting this report more rigorously than the last climate assessment, which was released in 2009.

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Superstorm Sandy caused $42 billion in damage in New York, including destroying the Breezy Point home of the Connolly family. Climate change can give such storms greater energy.

Problems for Americans

The stated goal of the National Climate Assessment is to inform the president, Congress, and the public about up-to-date science on climate change and its effects in the U.S.

The report warns that the average temperature across the U.S. has risen 1.5 degrees Fahrenheit since recordkeeping began in 1895. Eighty percent of that warming has occurred since 1980.

That amount of climate change has started causing problems for Americans in sectors ranging from construction and transportation to agriculture and forestry to health, the report says.

It says that more wildfires, decreased air quality, insect-borne diseases, and food- and waterborne diseases will take an increasing toll on human health, especially among children, the elderly, and the vulnerable.

"Climate change will, absent other changes, amplify some of the existing health threats the nation now faces," such as asthma and allergies, the report warns.

It says that extreme weather and sea-level rise is causing damage to buildings, roads, railways, runways, and other facilities in many regions.

Climate change is also disrupting natural systems and displacing species, the report cautions, which could impact the ability of ecosystems to provide useful "services" like flood control and watershed maintenance.

"Many agricultural regions will experience declines in crop and livestock production from increased stress due to weeds, diseases, insect pests, and other climate change-induced stresses," the report says.

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