The agency calls the program, to be dubbed ABoVE — Arctic Boreal Vulnerability Experiment — a “major field campaign.” It will send teams of scientists out into the field in Alaska and Canada, but also draw on NASA’s strength in satellites and remote sensing to get a better handle on what is happening to the the remote world above the Arctic Circle. Twenty-one initial field research projects have been green-lighted as part of an eight to ten year campaign, which is being launched out of NASA’s Terrestrial Ecology Program.
“The Arctic really is the canary in the coalmine,” says NASA’s Charles Miller, deputy science lead to the ABoVE project. “Things are changing in the Arctic at least twice as fast as the global average, and the systems in the Arctic, from the ecosystems to the sea ice to the permafrost, are thought to be very very susceptible to these environmental impacts.”
President Obama Tuesday focused attention on one change in particular that has reverberating effects — the loss of Alaska’s glaciers, which not only harms natural features that are crucial to the state’s tourism industry, but also has many attendant environmental consequences.
“There is a growing appreciation of how glacial melt, permafrost melting, and warmer and drier conditions are driving both insect outbreaks and wildfires, and this collective response to a warming climate is what is giving urgency” to the new research endeavor, says Doug Morton, an Earth scientist with NASA’s Goddard Space Flight Center.
To underscore the dramatic changes, Morton pointed to the following map, which is based on data from NASA’s GRACE (Gravity Recovery and Climate Experiment) satellites, twin instruments that circle the Earth and measure the tug of gravity from below. Areas with variations in mass cause the satellites to become closer to or more distant from one another, and this can be measured with high precision.
As a result, it is possible to measure things like “changes in Earth’s gravity from movement of water across the Earth’s surface,” as Morton puts it. Here’s the result, as of April of this year, and look in particular at Alaska and western Canada:
The image above initially drew a lot of attention in the context of the California drought, but Morton explains that it captures much more than changes in groundwater. It also captures changes in the mass of ice. Terrestrial water storage, which is shown in the map above, “consists of groundwater, soil moisture and permafrost, surface water, snow and ice, and wet biomass,” notes one NASA researcher. It “tends to be dominated by snow and ice in polar and alpine regions, by soil moisture in mid-latitudes, and by surface water in wet, tropical regions such as the Amazon.”
“We’re able to tell that there’s less water and ice weighing down the Alaska Range …and the amount of ice that’s been lost would be about knee deep across the entire mountain range,” says Morton. The Alaska Range includes not only Denali — the U.S.’s highest peak, which President Obama just officially gave its traditional name — but also numerous other glaciers.
“The weight of water, how much ice and snow and surface groundwater we’ve lost, is really a profound measure of how much this landscape has changed over a decade,” Morton continues.
But what the new NASA research endeavor focuses on is how changes like this lead to follow-on effects. For instance, melting ice earlier in the year dries out the ground, which can in turn set the stage for gigantic wildfires — this year’s blazes took out over 5 million acres in the state — which in turn sets the stage for the loss of permafrost, the frozen ground beneath, which is exposed to warmer temperatures once the forests above it burn away.
Extreme fire “takes the cover off of the permafrost, and its protected layer goes away, so the permafrost is now more vulnerable to thaw and change,” says NASA’s Miller.
And that sets the stage for emissions of carbon dioxide and methane to the atmosphere from permafrost — which contains the carbon-rich frozen remnants of past plant life — which in turn sets the stage for more global warming.
But there are many unresolved question about a process like this. For instance, notes Miller, there is also considerable research documenting what is called Arctic “greening” — the extension of plant growth into new areas as warming comes on strong, and the tundra becomes more supportive of plants that once could not survive the harsh conditions there. More plants means more pulling of carbon dioxide back out of the atmosphere again. So could this offset permafrost losses?
“That is one of the key questions that we do not know [the answer to] and for which our current best models give us conflicting information,” says Miller. “We really just don’t know.”
So in sum, President Obama has drawn national and global attention to Alaska’s and the Arctic’s rapid transformation — but we’re still going to need a lot of hard scientific work, on the ground in remote places, to decipher the consequences for the entire globe.
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