USA — A new federal scientific report says global warming is rapidly turning America the beautiful into America the stormy, sneezy and dangerous. And those shining seas? Rising and costly.
The new National Climate Assessment, released Tuesday, concludes that the harms of global warming will become more and more disruptive across the nation throughout this century and beyond. The report emphasizes how warming and its all-too wild weather are changing daily lives, even using the phrase “climate disruption” as another way of saying global warming.
— Climate change in Colorado —
Colorado is included in southwest region in the report. The six state region, it says, has increased heat, drought and insect outbreaks all linked to climate change and resulting in increased wildfires. The report also found the region has declining water supplies, reduced agricultural yields, health impacts in cities due to heat, and flooding and erosion in coastal areas.
The report finds that temperatures in the decade between 2001-2010 were the warmest on record, with an average temperature almost two degrees Fahrenheit warmer than historic averages. It also predicted that if global emissions continue to rise, average temperatures in the southwest region could rise by as much as 9.5 degrees by some time between 2070-2099.
If emissions are “substantially reduced,” the report reduced temperature increase during the same time frame by 3.5 to 5.5 degrees.
“Summertime heat waves are projected to become longer and hotter, whereas the trend of decreasing wintertime cold air outbreaks is projected to continue,” the report says.
Because the southwest has the highest percentage of population living in cities, the report says the heat may cause repercussions for public health. The authors suggest that as high temperatures or heat waves are magnified by the urban heat island effect, the energy system will become stressed and thereby increase the possibility of brownouts or power outages. Without adequate cooling, populations will be subjected to the heat and face increase chance of illness or death.
By the end of the century, the report projects Colorado’s average snowfall will be reduced to 74 percent of what it was in the 30 years preceding 2000. Additionally, the report predicts the snow will melt earlier because of a layer of dust and soot resulting from agriculture and development.
Warmer winters and dryer conditions due to climate change are referenced in the report as causes of exacerbated bark beetle outbreaks leading to dead trees and wildfire danger. Other factors cited as increasing wildfire danger include non-native grasses and the federal policy of fighting fires, which allowed fuels to accumulate.
The report recommends prescribed burning, mechanical thinning and retention of large trees.
“These adaptation measures also reduce emissions of the gases that cause climate change because long-term storage of carbon in large trees can outweigh short-term emissions from prescribed burning,” the report says.
— Recommendations for the future —
But the 840-page report says it’s not too late to prevent the worst of climate change. The White House is highlighting the science and effects of warming as it tries to jump start often-stalled efforts to curb heat-trapping gases.
The federal report indicates that stabilizing human carbon dioxide emissions would not stabilize the amount of the gas in our atmosphere. Instead, it says the concentration would continue to increase unless emissions are reduced “far below present-day levels.”
“Carbon dioxide is removed from the atmosphere by natural processes at a rate that is roughly half of the current rate of emissions from human activities,” the report says.
To reduce emissions enough to reduce greenhouse gasses in the atmosphere, the report says global carbon dioxide emissions would need to be limited at 44 billion tons per year within the next 25 years and decline thereafter. In 2011, the report estimates global emissions were around 34 billion tons.
“The challenge is great enough even starting today, but delay by any of the major emitters makes meeting any such target even more difficult and may rule out some of the more ambitious goals,” the report says.
Other efforts recommended in the report include researching new energy technologies that produce less carbon dioxide, researching behavioral science to maximize participation in future efforts and increasing the uptake of carbon dioxide through land-use and forestry.