Summit County Citizens Voice

‘High confidence’ of the mechanisms driving extreme weather

June 2012 global temperature anomalies. Courtesy NASA.

MUNICH, GERMANY — With the fundamental science of global warming mostly settled (increasing greenhouse gas emissions trap heat), researchers are moving into new realms, including the possible links between climate change and extreme weather.

And while it’s hard to show direct causal links, more scientists are acknowledging that global warming is at least setting the stage for more extreme weather.

“It is critical to understand that the link between climate change and the kinds of extremes that lead to disasters is clear,” Stanford climate researcher Chris Field said this week to the people who need to hear that message the most — lawmakers in Congress.

Testifying this week at a contentious U.S. Senate hearing on climate change, Field said it’s time to prepare for more flooding, drought and extreme heat.

Just as speeding increases the chance of having a car accident, climate change intensifies the risk of heat waves, droughts and heavy precipitation,  said Field, a senior fellow at the Stanford Woods Institute for the Environment.

“We can point clearly to the causal mechanism, but it’s still difficult to predict exactly when or where the crisis … will occur,” he said. “But still, we can have high confidence in the driving mechanism.”

Field said we can reduce the risk of a weather-related disaster with measures such as disaster preparations, early warning systems and well-built infrastructure.

While climate change’s role in tornadoes and hurricanes remains unknown, Field said, “the pattern is increasingly clear” when it comes to heat waves, heavy rains and droughts.

The hearing came on the heels of months of intense heat waves and massive wildfires. A disastrous drought still affects more of the U.S. than any drought in almost 25 years. Last year alone, the U.S. endured 14 climate-related disasters that each caused least $1 billion dollars in damage, according to written testimony Field prepared for the hearing.

Field is a Stanford professor of biology and environmental Earth system science and director of the Department of Global Ecology at the Carnegie Institution for Science. He was part of a group of researchers who shared the 2007 Nobel Peace Prize for their climate change work with the United Nations Intergovernmental Panel on Climate Change.

Citing studies from the IPCC, the U.S. National Academy of Sciences and the U.S. National Oceanic and Atmospheric Administration, among other scientific organizations, Field told the committee that climate change will lead to more frequent and intense extreme weather that affects larger areas and lasts longer. This, Field said, is a recipe for “unprecedented extreme weather and climate events.”

At the hearing’s close, Field explained his objective.

“What we’re trying to do is provide sufficient information for policymakers to make good decisions to try to figure out ways to avoid the damages that come from climate change without providing unacceptable costs to the rest of society. And we’re really trying to find smart ways to move forward, recognizing what’s happening, recognizing what the risks are and that there are consequences of using the atmosphere as a dump for greenhouse gasses just the same way there are consequences of making changes in the economy that are intended to alleviate those damages.”

Filed under: climate and weather, Environment, global warming Tagged: | climate, climate change, extreme weather, global warming, Intergovernmental Panel on Climate Change