Nowhere on Earth is climate change happening faster than in the Arctic, where the island of Greenland – a colony of Denmark that's home to about 56,000 full-time residents – stands as one of the most visible symbols of the impacts that are already being felt.
Warming temperatures are making it possible to mine once-inaccessible and vast deposits of gold, uranium and diamonds, while at the same time the ice sheet that covers most of the island is melting more rapidly today than in decades.
In March, scientists reported that the pace of melting on parts of Greenland's ice has tripled in the last decade, suggesting that "the sleeping giant is awakening ... and given likely continued Arctic warming, that it's not going back to bed," according to glaciologist Jason Box.
Browse the photos above for a tour of Greenland's stunningly beautiful frozen landscape, which is changing in ways we're just beginning to comprehend:
It's one of the biggest things on Earth. The Greenland ice sheet spans about 656,000 square miles and measures about 1.9 miles deep at its thickest point. It covers about 80 percent of the island of Greenland, which is about three times the size of Texas. By contrast, the Antarctic ice sheet covers about 14 million square miles, or an area larger than the size of the U.S. and Mexico combined.
The ice comes from snow. The ice sheet is made up of layers of compressed snow, much of which is more than 100,000 years old. Trapped in the ice are tiny air bubbles that contain the concentrations of carbon dioxide and other greenhouse gases from thousands of years ago. These records of ancient climates are a critical piece in the puzzle of how Earth has warmed and cooled throughout human history (and long before).
It'll take a very, very long time to melt. Scientists estimate that if all the ice that today covers Greenland – about 684,000 cubic miles – melted away completely, it would raise the world's oceans by about 23 feet, which would put just about every coastal city in the world under water. This won't happen anytime soon, however. Most climate change scenarios say it would take thousands of years for all of Greenland's ice to melt.
Ian Joughin PSC/APL/UW
Taken on an expedition to Greenland's North and South lake sites by a team from the University of Washington and the Woods Hole Oceanographic Institution in July 2010, this photo gives an up-close view of how quickly the island's ice sheet is melting.
But it's already contributing to sea level rise. Over the past 20 years, the melting of the Greenland ice sheet has been responsible for roughly a sixth of the annual rise in global sea levels, adding about 0.5 of the 3.2 millimeters by which the world's oceans rise each year.
Greenland's melting can affect weather and temperature patterns elsewhere. In the 1960s, rapid melting of Arctic freshwater ice sent what is known as the Great Salinity Anomaly into the ocean, creating a thin layer of freshwater that floated on top of the salty North Atlantic and insulating it from contact with the atmosphere.
Why is this worrisome? Because the global ocean soaks up a significant amount of the carbon dioxide humans pump into the atmosphere, anything that interferes with its ability to pull CO2 from the air to the sea depths could create a feedback loop that would worsen global warming.
Its melting is accelerating. According to the aforementioned study in the scientific journal Nature Climate Change, the Greenland ice sheet's northeast region had been stable for a quarter century until the first years of the 21st century.
But around 2003, warming air temperatures began melting the northeastern ice sheet much more quickly than before, and its Zachariae glacier has since retreated by more than 12 miles. That's especially fast when compared with the Jakobshavnglacier in southwestern Greenland, which has taken about 150 years to retreat just over 20 miles.
"We're seeing an acceleration of ice loss," Michael Bevis, a professor of earth sciences at Ohio State University and co-author of the study, told USA Today. "Now, there's more ice leaving than snow arriving."Follow @terrellwrites
MORE: The Melting of the Greenland Ice Sheet