Their report, the second of a two-part National Climate Assessment project, claims that rising temperatures have already affected major industries and that Americans are now being directly affected.
"The impacts of global climate change are already being felt in the United States and are projected to intensify in the future—but the severity of future impacts will depend largely on actions taken to reduce greenhouse gas emissions and to adapt to the changes that will occur," the authors write.
The report catalogs the steps the U.S. is already taking in response. They include water conservation in the Colorado River Basin; Nebraska’s extension program that helps ranchers cope with drought; efforts in Hawaii to promote coral reef recovery; and investments in Louisiana flood control operations.
"In Alaska, a tribal health organization is developing adaptation strategies to address physical and mental health challenges driven by climate change and other environmental changes," the authors write. "As Midwestern farmers adopt new management strategies to reduce erosion and nutrient losses caused by heavier rains, forest managers in the Northwest are developing adaptation strategies in response to wildfire increases that affect human health, water resources, timber production, fish and wildlife, and recreation."
Rise of 1.8 degrees Fahrenheit
The report says the annual average temperatures have increased by only 1.8 degrees Fahrenheit over the last 118 years, though it says much of the change is concentrated in the period between 1986 and 2016.
The report is being issued at the beginning of what is projected to be a particularly cold winter. A NASA scientist recently reported that there has been a lack of sunspot activity throughout 2018, and that could lead to what he called a "space age record" for cold temperatures this winter.
Ultra-violet radiation from sunspots is thought to agitate particles in the Earth's atmosphere, creating heat. Without the sunspot activity, that heat will be absent.
Other scientists cited in the Daily Mail say these changes take place in the atmosphere high above the earth and are not likely to affect the weather that much on the surface.