Last year, the U.S. Global Change Research Program released the third U.S. National Climate Assessment, which summarizes the impacts of climate change in the United States, both now and in the future. A team of more than 300 experts produced the report, with extensive input from a 60-member Federal Advisory Committee, the public, and the broader scientific community.
One of the exciting things about last year’s report was its new emphasis on the user community. Not only is the report more detailed than previous iterations in summarizing impacts relevant to different states and regions around the country, as well as to different industries, but its format is a highly interactive and visual website. At the same time, all the data that went into the analysis is available on the website for scientists who want to better understand the analysis.
The point, of course, is that it is important for the public to understand some of the very serious implications of climate change, and it is equally important for the scientific community to help explain the issue in a way the public can both grasp and use to make decisions.
Two of the lead authors of the National Climate Assessment recently took up the challenge by writing about the report—and what has changed over the last year—in an editorial in a community newspaper.
Below is their article. We hope this encourages other scientists to follow their example!
—Alexandra Shultz, Director of Public Affairs, AGU; email: [email protected]
Citation: Shultz, A. (2015), Spreading the word about climate change, Eos, 96, doi:10.1029/2015EO029509. Published on 6 May 2015.
Climate Change and Our Nation
Republished by permission of The News-Gazette. Permission does not imply endorsement.
By Don Wuebbles and Jerry Melillo
One year ago marked the release of the National Climate Assessment, the most comprehensive analysis to date of how climate change is affecting every corner of our nation — our health, water, food and more. The assessment made clear that climate change is not just a problem for the future, but is happening now across the United States. Americans are already being affected by increases in heat waves and heavy downpours, rising sea level, and other impacts of climate disruption.
Recent changes are occurring more than 10 times faster than past natural changes, and many lines of evidence make clear that emissions from the burning of coal, oil and natural gas are the primary cause of the last half-century’s warming.
The assessment also showed that large reductions in global emissions of heat-trapping gases could reduce future climate change and avoid some of its most damaging impacts.
In the year since the assessment’s release, new scientific developments have told a consistent and compelling story that points to the need for urgent action to address this great challenge.
NASA and NOAA analyses show that 2014 was the warmest year on record. Nine of the 10 hottest years have taken place since 2000. Over the last five decades, each decade has been warmer than the previous one, and this decade looks like it will be warmer still. So far in 2015, January through March was the warmest first quarter on record globally.
And we understand why. Atmospheric carbon dioxide traps heat, and its level in early 2015 eclipsed a long-standing prehistoric high, as it reached a concentration of 400 parts per million, a level that has not occurred in millions of years.
For the last 200,000 years, the period of human habitation on Earth, the atmosphere’s carbon dioxide level has fluctuated between 170 and 280 parts per million, as shown by records preserved in air bubbles trapped in polar ice.
Through the burning of fossil fuels and the clearing of forests, we have pushed carbon dioxide levels about 43 percent above the high end of this range. Human activities have also increased the atmospheric amounts of other important heat trapping gases such as methane and nitrous oxide.
The warming resulting from these increases is leading to massive melting of ice at the poles, and the past year has revealed several disturbing new developments.
In February 2015, the cap of winter sea ice in the Arctic covered far less area than in any previous late winter period. And satellites have now more extensively than ever mapped Earth’s two large polar ice sheets on Greenland and Antarctica, and found that the ice on both is declining at unprecedented rates, adding to global sea level rise (which surged in the latter half of 2014).
A new study of a rapidly melting section of the West Antarctic Ice Sheet reveals this sector to be in an irreversible state of decline. This sector alone contains enough ice to raise global sea level by 4 feet, and it is melting faster than expected.
Researchers say these new findings require an upward revision to current sea level rise projections.
New studies have also found evidence of increasing societal impacts occurring due to climate change. A new assessment of human health effects developed by leading health experts is now available for public and expert review. Recent research also suggests potentially much larger effects on agriculture than prior studies.
That’s the bad news. But good news can be found in recent studies that show the value of reducing emissions. Not only will such emissions cuts reduce future climate change, they will also improve our health in other ways, and save us money.
For example, a new study examining the true costs to society of continuing to burn fossil fuels finds that when the effects of air quality on human health from energy production are included, the actual costs of burning coal, oil and natural gas are far higher than the use of solar and wind power. This is important information that can inform our energy choices.
Other good news can be found in the rapidly-growing capacity and declining prices of solar and wind power.
We report the latest science, hoping that it will help us make better decisions.
After all, as our late colleague F. Sherwood Rowland, a Nobel Laureate, said, “What’s the use of having developed a science well enough to make predictions if, in the end, all we’re willing to do is stand around and wait for them to come true?”
Don Wuebbles works in the Department of Atmospheric Sciences at the University of Illinois, Urbana. Jerry Melillo works in the Marine Biological Laboratory, Woods Hole, Mass.