Over the next 70 years, the Earth is expected to warm about as much as it did during the thousands of years from the depths of an ice age to the midst of a benign period like the one we currently are in.
That's the conclusion of a major federal report, the National Climate Assessment, released in January and up for public comment until April.
At more than 1,000 pages long, the draft of the National Climate Assessment pulls together the latest climate research into a single document. Its purpose is to better inform officeholders and the public of the changes taking place.
Given the unprecedented pace of planetary change, the report offers little hope for a warmer world being an easier one to live in.
Water scarcity, food supplies and natural disasters will tug at the fabric of society.
“Everyone on Earth will be affected by the changes that are occurring,” according to the report.
If the Earth were to follow its normal cycle, the next ice age would start sometime in the next 1,500 years. Humans have so altered the atmosphere, the report concludes, that the ice age has been delayed indefinitely.
According to the National Climate Assessment, the average temperature of the United States has warmed about 1.5 degrees since 1895, and more than 80 percent of that has occurred since 1980.
As a result, climate change already is affecting the American people, the report notes.
Over the next few decades, another 2- to 4-degree increase in average temperature is expected in most areas. This warming is locked in by increased concentrations of global warming gases in the atmosphere and their effect on weather.
Politicians may not realize it, but the fights in Congress and in the halls of governments worldwide aren't about the climate that will confront the next two generations. That future warmth is unavoidable.
Instead, the fight is whether to curb emissions now so that even more extreme changes don't occur at the end of the century. By then, average temperature will increase by about 3 to 10 degrees or more, according to the report. Less if humans act to curb emissions, more if they don't.
To read the report or offer a comment, go to www.globalchange.gov.
For a look at how climate change is expected to affect agriculture in Nebraska and Iowa, check out the Monday edition of The World-Herald.
Source: National Climate Assessment