This Woman Tracks Icebergs for the International Ice Patrol

Yes, that’s a thing, and it’s essential for safe shipping in the North Atlantic.

Commander Gabrielle McGrath entering the aircraft where she and her team conduct their missions to search for icebergs in the North Atlantic. Using HC-130J aircraft, their operations are based out of St. John’s, Newfoundland, for a nine-day period twice a month.

Photographer: Caroll Taveras for Bloomberg Businessweek

At Work With is our ode to unsung professions. This week, meet a Coast Guard officer who patrols the North Atlantic for icebergs.

Gabrielle McGrath, U.S. Coast Guard Ice Patrol

  • Age 42
  • Job title Commanding officer
  • Industry U.S. military
  • Location Connecticut
  • Years at Coast Guard 21

This is embarrassing, but I’ve never heard of the International Ice Patrol.
It’s a lesser-known entity to the U.S. Coast Guard. We’re at 17 people now. I joined in 2006 and have been commanding officer since 2013.

And you, what, patrol icebergs?
Following the Titanic disaster in 1912, several countries founded the International Convention for the Safety of Life at Sea that put in place safety regulations and also created the International Ice Patrol, which tracks icebergs and alerts passing ships to their presence. The Ice Patrol is run by the U.S. Coast Guard, but there are 17 contributing nations that pay for our work.

Why do you patrol only the North Atlantic?
Because it’s the only place in the world where the path of icebergs intersects with shipping lanes. We can track up to 10,000 icebergs in any one season. It takes one to three years from when an iceberg calves off a glacier to when it gets to our area.

Commander McGrath in her office at a Coast Guard base in Connecticut.
Photographer: Caroll Taveras for Bloomberg Businessweek

So how do you track an iceberg anyway?
In 1913, when the Ice Patrol started, its ship would station itself near an iceberg and broadcast a signal out to all ships within range saying, “Hey, this is where the iceberg is.” Once the iceberg melted, they’d go on to the next one. After World War II, we started using aircraft. For a long time it was mostly aerial photography. In the 1980s we started using radar. Something we’ve brought into play now is satellite imagery analysis. We’ve been working on it for decades, and it’s come to fruition just this year.

Do you do this year-round?
February through July we fly. We’re typically in the air seven to nine hours a day, locating radar targets and collecting data. We find an iceberg and predict its path and deterioration based on factors including sea surface temperatures, wave heights, ocean drift.

In the base’s library, a painting of a Coast Guard plane flying over icebergs.
Photographer: Caroll Taveras for Bloomberg Businessweek

Once you find an iceberg in a shipping lane, what do you do? Can you get rid of it?
In the 1950s and ’60s we experimented with destroying icebergs by, say, placing bombs on them, but one large iceberg is easier to track than if you break it up into small pieces. So now we tend to leave them alone. We don’t do GPS tracking because as the iceberg melts, the tracking device will fall off.

Has the number of icebergs changed now that the ocean temperature is rising?
What we’ve noticed is that the season of severity is based more on atmospheric conditions in the area around Greenland than long-term changes to climate. In 2013 we had onshore winds and had only 13 icebergs in the shipping lane. In 2014 the pattern shifted and we had 1,546 icebergs. 


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