Late last week, the White House announced something seemingly mundane — a series of new topographic maps of the U.S.’s only Arctic state, Alaska. Ninety percent of the enormous state has now been mapped at a far higher resolution than ever before – 2 meters — through satellite-based imaging combined with high-powered computing.
The announcement represented the fulfillment of a pledge that president Obama made almost exactly a year ago in Kotzebue, Alaska, when he visited the state to highlight climate change.
Mapping may sound rather dull — but the more closely you examine what has been accomplished here, the more you realize it is the kind of advance that could have a profound impact on scientific understanding of the entire Arctic, the most rapidly changing part of the globe.
“Elevation data is one of the most fundamental datasets for both earth science and all aspects of mapping and cartography,” said Paul Morin, who led the research at the University of Minnesota’s Polar Geospatial Center, in collaboration with the National Science Foundation and the National Geospatial-Intelligence Agency. “It tells you the shape of the Earth and it tells you what the Earth is. That’s key for all kinds of things, from the biology to plate tectonics and glaciology.”
“It’s a complete game-changer,” added Fabien Laurier, a senior policy adviser at the White House’s Office of Science and Technology Policy. “Elevation may not sound all that exciting, but the range of applications is almost limitless.”
The new data will complement an ongoing project by the U.S. Geological Survey to map Alaska at a still higher resolution using lasers and radar.
The lack of good maps of Alaska was covered extensively by the Post’s Lori Montgomery in 2014. As she put it then:
Alaska, it turns out, has never been mapped to modern standards. While the U.S. Geological Survey (USGS) is constantly refining its work in the lower 48 states, the terrain data in Alaska is more than 50 years old, much of it hand-sketched from black-and-white stereo photos shot from World War II reconnaissance craft and U-2 spy planes.
Errors abound. Locals tell of mountains as much as a mile out of place. Streams flow uphill, and ridges are missing because a cloud happened by when the photo was taken.
Rather than flying planes over Alaska, the new maps were created based on high-resolution telescopic images captured by polar orbiting satellites operated by DigitalGlobe. Images of a 17-by-120 kilometer area were snapped once, and then snapped again, 45 seconds later — by which time the rapidly orbiting satellites had already moved a large distance away. Thus, each image showed the same square of terrain but at different angles.
Then, a supercomputer dubbed Blue Water, at the University of Illinois at Urbana Champaign, computed the elevation of all objects in the landscape by rapidly comparing every object in every pair of images.
Computing power is what made this possible. “We calculated that if we were to try to do this on a very powerful desktop gaming computer, it would take you about 20,000 years to run the same data through,” said Morin.
And the Alaska maps are just a beginning. An elevation mapping of the entire Arctic, based on the same technique, is slated to be released by the close of 2017.
“The highest resolution for publicly available maps of the Arctic region is 30 meters, compared to less than 1 meter for the rest of the United States and the rest of the industrialized world,” says Mark Brzezinski, executive director of the Arctic Executive Steering Committee at the White House.
As the Arctic comes into high resolution, Morin and Laurier said scientists will be able to study the impacts of climate change by satellite. As glaciers melt, they slump. As permafrost thaws, the ground collapses. As wildfires rage, trees vanish.
And all of these types of changes can, increasingly, be quantified remotely.
“If you’re trying to figure out the amount of carbon in a stand of trees, you can actually more precisely estimate that now, because you’ll know the height of the trees, and if you can tell what type of trees they are, you can tell what carbon’s in there,” said Morin.
Brzezinski added that, at a time when numerous Alaskan native villages are either contemplating, or on the path towards, relocation in the face of rising seas and declining sea ice, digital elevation mapping can tell you where it might be a safe place to relocate.
In sum, at a time of dramatic Arctic change, a sinking of just a few meters will now be something that scientists can document from afar. Expect a wealth of research to result.
We can’t stop the dramatic transformation of the Arctic, perhaps, but we will be able to observe it at extremely high resolution.
“By the end of 2017, all of us, with access to a computer, can zoom in to places that were as remote as can be until this mapping is revealed,” said Brzezinski.
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