Oct 30, 2018

Huge Antarctic iceberg breaks off Pine Island Glacier

The calving front of the Pine Island Glacier, seen by a NASA aircraft in 2016. Image: NASA IceBridge.

An iceberg about five times the size of Manhattan has broken off the Pine Island Glacier in West Antarctica over the past 24 hours, an ominous sign of the continued retreat of this fast-flowing mass of ice. Like many other marine terminating glaciers in Antarctica, this glacier is retreating over time, and increasing the movement of ice into the sea.

Why it matters: While this iceberg itself is not record-breaking — it ranks as the sixth-largest iceberg to break off the Pine Island Glacier since 2001 — it illustrates the continued instability of marine-terminating glaciers in parts of the icebound continent.

The details: The iceberg had first appeared as a rift across Pine Island Glacier in September, before leading to the calving of about 300 square kilometers, or 116 square miles, of ice. The largest individual iceberg measures about 226 square kilometers in area, or 87 square miles.

Stef Lhermitte, a geoscientist at the Netherlands' Delft University of Technology who closely tracks Antarctic ice, tweeted that the glacier front, where the ice meets the sea, has now receded by about 5 kilometers, or close to a mile inland compared to recent decades.

  • Ice shelves, such as the one at the Pine Island Glacier, act like door stops to the land-based ice behind it. Once they diminish, due to a combination of warming from the ocean below and air temperatures above, it's more likely that inland ice will collapse into the sea, raising global sea levels.

Determining the amount of future ice loss from Antarctica is the biggest source of uncertainty in sea level rise projections, but recent studies have suggested that Antarctic ice melt is likely to be at the higher end of the scale.

  • Recent research published in Nature Climate Change, found that "ice losses from Antarctica have accelerated during the past 25 years," and that 40% of the continent's sea level rise contribution has occurred during just the past 5 years.
  • Antarctica lost 1,883 billion tons of ice between 2007 and 2017, which was significantly higher than scientists estimated in a seminal report published in 2013.

The bottom line: The new iceberg is significant for reflecting trends taking place around Antarctica, which many climate scientists find worrisome.

Go deeper: West Antarctic ice melt poses unique threat to U.S., Antarctica has lost nearly 3 trillion tons of ice since 1992

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Trump announces 30-day extension of coronavirus guidelines

President Trump announced on Sunday that his administration will extend its "15 Days to Slow the Spread" guidelines until April 30 in an effort to stop the spread of coronavirus, which has now infected more than 130,000 Americans and killed nearly 2,500.

Why it matters: Top advisers to the president have been seeking to steer him away from Easter as an arbitrary deadline for the U.S. to open parts of its economy, amid warnings from health officials that loosening restrictions could cause the number of coronavirus cases to skyrocket.

Go deeperArrow28 mins ago - Health

Coronavirus dashboard

Illustration: Sarah Grillo/Axios

  1. Global: Total confirmed cases as of 5 p.m. ET: 716,101 — Total deaths: 33,854 — Total recoveries: 148,900.
  2. U.S.: Leads the world in cases. Total confirmed cases as of 5 p.m. ET: 136,880 — Total deaths: 2,409 — Total recoveries: 2,612.
  3. Federal government latest: The first federal prisoner to die from coronavirus was reported from a correctional facility in Louisiana on Sunday.
  4. Public health updates: Fauci says 100,000 to 200,000 Americans could die from virus.
  5. State updates: Louisiana governor says state is on track to exceed ventilator capacity by end of this week — Cuomo says Trump's mandatory quarantine comments "panicked" some people into fleeing New York
  6. World updates: Italy on Sunday reports 756 new deaths, bringing its total 10,779. Spain reports almost 840 dead, another new daily record that bring its total to over 6,500.
  7. What should I do? Answers about the virus from Axios expertsWhat to know about social distancingQ&A: Minimizing your coronavirus risk
  8. Other resources: CDC on how to avoid the virus, what to do if you get it.

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Trump touts press briefing "ratings" as U.S. coronavirus case surge

Photo: Drew Angerer/Getty Images

President Trump sent about a half-dozen tweets on Sunday touting the high television ratings that his coronavirus press briefings have received, selectively citing a New York Times article that compared them to "The Bachelor" and "Monday Night Football."

Why it matters: The president has been holding daily press briefings in the weeks since the coronavirus pandemic was declared, but news outlets have struggled with how to cover them live — as Trump has repeatedly been found to spread misinformation and contradict public health officials.