Virginia Burkett on climate impacts in U.S.
Virginia Burkett: The changes in climate that are projected for the next few decades are likely to be greater than what we’ve seen over the past 100 years.
Virginia Burkett is Chief Scientist for Global Change Research at the U.S. Geological Survey. Dr. Burkett spoke of how a warming climate might affect different parts of the U.S.
Virginia Burkett: In Alaska, the most important impacts would include the loss of sea ice and the decline of permafrost. In the arid southwestern United States, it would be dramatic declines in rainfall and snow cover. And that might lead to more droughts and widespread fires. In the southeast, where I live, it would be rising sea level and stresses on water supplies, crops and trees, and even human health.
Dr. Burkett, who’s based out of Louisiana, studied the potential risk to industry from sea level rise caused by melting glaciers and warmer oceans.
Virginia Burkett: We just completed a study with the U.S. Department of Transportation about the effects of climate change on transportation systems between Mobile, Alabama, westward over to Galveston, Texas. And our analysis shows that a relative sea level rise of two feet, which is entirely plausible this century, would permanently flood about 19 percent of all the interstate highway miles, 64 percent of the freight facilities along the ports, 68 percent of the non-freight facilities.
Burkett warned of the possibility of ‘abrupt climate change’ – rapid, large-scale climate change that could take place in just a few decades.
Virginia Burkett: We’ve seen a decline in snow cover, glaciers, and sea ice, actually, much more rapidly than we had projected. But the worst case scenario would be a large-scale change in the climate system that takes place in just a few decades or less, that persist and causes substantial disruptions to human systems and natural ecosystems. And we refer to this as ‘abrupt climate change.’
One of the most troubling signs of climate change is the decline of the Greenland ice sheet, says Burkett.
Virginia Burkett: The loss of the Greenland ice sheet and why it’s important to us, there are two basic reasons. One, is that trapped in that ice is additional six meters of sea level rise. So if that ice sheet were to completely disappear, sea level globally would rise siz meters, or more. Secondly, the influx of all of that freshwater into the ocean would weaken thermohaline circulation that warms a large part of the northern hemisphere, such as in Europe.
According to Burkett, climate model experiments generally predict the most rapid warming at high latitudes.
Virginia Burkett: We have to remember that virtually all climate model experiments show accelerated warming around the planet over the coming decades, with the warming most rapid at high latitudes, such as Alaska and Canada.
Along the Alaska coast, the vulnerability is exceptionally high due to rising temperatures, which causes the permafrost to thaw, so that the coastline is basically collapsing, and sea ice has retreated away from the coast. So now the coast is being eroded by storms and wave action at a much higher rate. The rate of erosion along the north slope of Alaska, for example, during the past twenty years, compared to the twenty years prior to that has more than doubled.
Rising sea level also threatens the Gulf coast area, says Burkett.
Virginia Burkett: A lot of the various industrial sectors along the Gulf coast for example, are very concerned about sea level rise. We just completed, a few months ago, a study with the U.S. Department of Transportation about the effects of climate change on transportation systems between Mobile, Alabama, westward over to Galveston, Texas. And our analysis shows that a relative sea level rise of two feet, which is entirely plausible this century, would permanently flood about 19 percent of all the interstate highway miles, 64 percent of the freight facilities along the ports, 68 percent of the non-freight facilities. And if sea level rose four feet, it would permanently flood 24 percent of the existing interstate miles, 72 percent of the freight facilities, nine percent of the rail miles, and possibly three airports. Even though a couple of those are in New Orleans and protected by levees.
Burkett offered her view of the role of science in combating climate change.
Virginia Burkett: It’s very simple. The role of science in my view on this or other major societal issues or minor is simply to inform policy. As a scientist, I do not advocate a particular course of action. Personally, I do hope that policy is set in the United States and elsewhere based on good science.
Our thanks to the US Geological Survey, celebrating the International Year of Planet Earth.