Mapping Arctic Tundra
For the last four years, Earth and Environmental Studies Professor Mark Chopping has been mapping changes in Arctic tundra on the Alaska North Slope with the help of a Terrestrial Ecology Program grant from NASA.
The first NASA Earth Observing System satellite became operational in 2000. “We hope to be able to map and quantify the changes in tall shrub cover in Arctic tundra over the period 2000 through 2012,” Chopping says. “Remote sensing of vegetation in the Arctic is challenging because of cloud cover, low sun elevation, currently low shrub cover and intrinsically dark surfaces.”
“Shrubs affect climate because they absorb more sunlight than other tundra vegetation in summer and they help snow insulate the land surface in winter from cold Arctic air, promoting permafrost thaw and soil microbial respiration,” Chopping explains. “This potentially releases large volumes of the greenhouse gases methane and carbon dioxide. By mid-century, we are likely to see very rapid and very large releases of these gases from Arctic soils.”
Chopping sees climate change as a bio-directional process. “It affects Arctic ecosystems and the changes in Arctic landscapes are affecting climate.”
Yet the impact of these changes is not confined to the Arctic. Changes in Arctic amplification—or surface warming at high latitudes—have the potential to cause extreme weather like cold spells, heat waves and drought even in New Jersey.
So far, mapping efforts have been confined to the Alaska North Slope. Chopping and Rocio Duchesne, an environmental management doctoral student, have conducted several field campaigns in Alaska. “We’ve constructed a large reference database,” Chopping says. “When we have tested our method, we will extend the mapping to the entire Arctic.”
Chopping’s project is part of the multi-agency North American Carbon Program. His goal is to construct a robust map series that will aid researchers from multiple disciplines who are studying changes in everything from Arctic wildlife habitats and carbon pools to permafrost thaw and snowmelt. “Although 12 years is a short period for most ecosystem change studies, the Arctic environment is changing so rapidly that we hope to detect a trend,” says Chopping.