Global Warming

US Government Report on Climate Change

Earth's climate is now changing faster than at any point in the history of modern civilization, primarily as a result of human activities, according to a long-awaited report released Friday by the federal government. The National Climate Assessment warns that extreme weather and climate-related events in the U.S. are worsening, and it reveals the economic and health toll of climate change.

The report, which is mandated by law, "concludes that the evidence of human-caused climate change is overwhelming and continues to strengthen, that the impacts of climate change are intensifying across the country, and that climate-related threats to Americans' physical, social, and economic well-being are rising."

The report's authors, who represent more than a dozen federal agencies, detail expected economic impact.

"The continued warming that is projected to occur without substantial and sustained reductions in global greenhouse gas emissions is expected to cause substantial net damage to the U.S. economy throughout this century, especially in the absence of increased adaptation efforts," the report says.

Climate change is expected to hurt the American economy by causing more damage to natural resources and infrastructure, including access to roads, the viability of bridges and the safety of pipelines.

The federal report says the last few years have smashed records for damaging weather in the U.S., costing nearly $400 billion since 2015.

When it comes to health, the report says increasing water and air temperatures and more intense extreme events are expected to heighten exposure "to waterborne and foodborne diseases, affecting food and water safety."

Climate change is also projected to increase the frequency and severity of allergic illnesses, including asthma and hay fever. And it will alter the geographic range and distribution of disease-carrying insects and pests, exposing more people to ticks that carry Lyme disease and mosquitoes that transmit viruses such as Zika, West Nile, and dengue, with "varying impacts" across regions.