Climate change could make every summer like 2012's

Nebraskans who wonder what climate change could portend for the state have a recent reference point: the summer of 2012. The worst drought in the region’s recorded history, it could be just a typical summer by century’s end, University of Nebraska-Lincoln scientists warn.

Don Wilhite, longtime climate scientist, led a discussion of climate change at the first Heuermann Lecture of 2014-15 Thursday. Wilhite and other UNL scientists discussed their new report “Understanding and Assessing Climate Change: Implications for Nebraska” before several hundred people at the Nebraska Innovation Campus Conference Center.

Although the extent of human beings’ contribution to climate change remains a point of political contention in the United States, Wilhite said there’s virtually no scientific doubt left. Ninety-seven percent of climate scientists now believe human behavior is changing the climate.

Although the Earth has gone through ice ages and warm periods throughout its history, the warming of the planet is occurring at a faster rate than ever before, and it’s become clear to scientists that shifting land use patterns, burning of fossil fuels and other actions are quickening the pace, Wilhite said.

He pointed to 10 indicators measured globally over decades, all of which indicate the earth’s climate is warming. They include temperatures over oceans and land, snow cover, ocean heat content and sea surface temperatures. Wilhite also said that July 2014 was the 353rd consecutive month with a global temperature above the 20th century average.

Wilhite acknowledged projections are not certain because it’s impossible to predict how human behavior might change in the coming decades to contend with climate change. Average temperatures in Nebraska could increase 4-5 degrees up to 8-9 degrees by 2071-2099. Days of 100-degree temperatures could increase by 13-16 per year, up to 22-25. The frost-free season, having already increased 5-25 days, could increase by another two weeks.

Wilhite pointed to the 2012 summer, when McCook and Lincoln experienced 37 and 17 100-degree days, respectively – 11 and 4.6 days more than normal.

“2012 would be an average summer” if climate change projections are accurate, Wilhite said.

Some regions of the United States would be “winners” in climate change, but “losers” would include the Great Plains, the Southwest and the Southeast, Wilhite said.

Other coauthors of the report offered some perspective in a question and answer session. Deborah Bathke, an assistant professor of practice in meteorology-climatology, said UNL is well-positioned with its variety of expertise to help find answers to climate change. She urged “a positive, solutions-oriented focus rather than a doom and gloom approach.”

Robert Oglesby, a professor of climate modeling at UNL, said the United States has a responsibility to provide leadership on the issue, but many politicians instead point to other countries, such as India and China, where rapid industrialization has had significant environmental impacts.

“We used to think of ourselves as leaders. Waiting to see how other countries act is not leading,” he said. “Do we have the will or do we not have the will?”

Wilhite said he hopes the UNL report will provide a foundation to state and federal policy makers. In addition to its summary of scientific evidence of climate change, he noted, the report features commentaries from several key sectors in Nebraska, including water resources, energy supply and use, agriculture, forestry, human health, ecosystems, urban systems, infrastructure and rural communities.

The entire report is available at go.unl.edu/climatechange

Heuermann Lectures focus on providing and sustaining enough food, natural resources and renewable energy for the world's people, and on securing the sustainability of rural communities where the vital work of producing food and renewable energy occurs. They are made possible by a gift from B. Keith and Norma Heuermann of Phillips, long-time university supporters with a strong commitment to Nebraska's production agriculture, natural resources, rural areas and people.

Lectures are archived at http://heuermannlectures.unl.edu.

For a World-Herald op-ed by IANR Vice Chancellor Ronnie Green, see: http://bit.ly/1rybmKs

More details at: http://go.unl.edu/j2qn