Every year, Arctic sea ice grows and extends through the winter. On March 7, 2017, Arctic sea ice reached its record lowest maximum.
On March 7, 2017, Arctic sea ice reached the lowest winter maximum on record. Source: NASA’s Goddard Space Flight Center.

You’ve probably heard about climate change, the loss of sea ice in the Arctic Ocean, and the loss of prime polar bear habitat. None of this is news.

However, you may not be aware of how alarmingly fast the Arctic Ocean is shedding sea ice.

Up until the 21st century, the loss of sea ice has been minimal. But now, scientists say a domino effect is occurring. As the oceans (and the world) heats up, more and more old Arctic sea ice is disappearing — and it is not being replaced.

As this remarkable video from NASA’s Goddard Space Flight Center shows, the retreat of Arctic sea ice has ramped up significantly in the past decade.

Old sea ice is important because it is thicker, and thicker ice can survive summertime in the Arctic. Without it, the Arctic will likely have an ice-free summer in the next decade.

“We’ve lost most of the older ice,” said cryospheric scientist Dr. Walt Meier of NASA Goddard Space Flight Center. “In the 1980s, multiyear ice made up 20 percent of the sea ice cover. Now it’s only about 3 percent. The older ice was like the insurance policy of the Arctic sea ice pack: as we lose it, the likelihood of a largely ice-free summer in the Arctic increases.”

Sea ice coverage in September 1991. Source: NASA's Goddard Space Flight Center.
Sea ice coverage in September 1991. Source: NASA’s Goddard Space Flight Center.

The loss of Arctic sea ice will have ramifications that exceed lost polar bear habitat. The cold waters of Arctic Ocean effectively act as a global AC unit. Without ice to insulate these waters, water temperatures will skyrocket.

The white coloration of sea ice and snow reflects sunlight back into the atmosphere, keeping Earth’s polar regions (and the rest of the planet) cool. Without the ice, the dark blue waters of the Arctic Ocean will absorb far more sunlight. In fact, summer sea ice reflects 50 percent of incoming radiation back into space while open water only reflects 10 percent.

Sea ice coverage in September 2016. Source: NASA’s Goddard Space Flight Center.

With all that said, the loss of sea ice during Arctic summers is changing the Arctic from a global AC unit into a global heater, and that doesn’t include the effects of carbon emissions, sea level rise, warming Arctic rivers, methane being released from melting permafrost, and increases in water vapor that traps radiation in the atmosphere, among other factors.

Are we beyond the tipping point to protect the Arctic (and our planet as we know it), or is it too far gone? Throughout the rest of the 21st century, we will see.