Pine Island Glacier, one of the fastest-shrinking glaciers in Antarctica, hastened its slide into the sea between 2017 and 2020, when one-fifth of its associated ice shelf broke off as massive icebergs, a study revealed.
Scientists studied the acceleration using high-res radar images, captured by satellites.
Scientists studied the acceleration using high-res radar images, captured by satellites.
Category
🤖
TechTranscript
00:00These high-resolution radar images show how recent collapses of the Pine
00:05Island Glacier ice shelf caused the whole mass of ice to speed up on its
00:09slide towards the sea. The images were captured by the Copernicus Sentinel-1
00:15satellites, which are operated by the European Space Agency and equipped with
00:20synthetic aperture radar, which takes what looks like black and white photographs
00:25but actually captures radio waves rather than visible light. Starting in 2015 the
00:31Copernicus Sentinel-1 satellites took snapshots of the Pine Island Glacier
00:35every 12 days and then after fall 2016 they began collecting data every six
00:41days. Researchers examined all the images collected between January 2015 and
00:47September 2020 and used the multitude of images to create detailed videos of the
00:52ice flow. According to these videos and models that the team developed, the loss
00:59of ice from the shelf allowed the glacier to speed up by about 12% between late
01:042017 and 2020. The glacier sped up another time in recent history between the 1990s
01:11and 2009 when warm ocean currents ate away at the underside of the ice shelf,
01:16destabilizing its structure and causing the glacier to accelerate toward open water.
01:21But this time this somewhat gradual melt driven process wasn't the primary cause for
01:27the speed up. Instead the dramatic and sudden calving of icebergs from the
01:32shelf drove this acceleration. These new findings hint that the entire ice
01:37shelf might collapse sooner than previously projected, within decades rather than
01:42centuries. This could hasten the whole glaciers collapse in turn. But that said we
01:49don't know exactly when that collapse might occur and for now the observed changes
01:53shouldn't drastically change Pine Island glaciers contribution to sea level rise. At present
02:00the glacier contributes about one-sixth of a millimeter of sea level rise each year. So
02:04even if that rate suddenly tripled, we're still talking about fractions of a millimeter. In the
02:10words of the first author, the changes are rapid and concerning but not
02:14immediately catastrophic. Nothing's going to happen overnight.