Under the Ice

To paraphrase J.R.R. Tolkien’s famous words in The Lord of the Rings, “It’s a dangerous business, clicking on a link. You glance at a story, and if you don’t watch out, there’s no knowing where you might be swept off to.”

This week I innocently clicked on a link to this story from the American Association for the Advancement of Science (AAAS).
Mysterious holes in Antarctic sea ice explained by years of robotic data (University of Washington, AAAS EurekAlert!)
In turn, that link led to this research study that was just published in Nature last week.
Antarctic offshore polynyas linked to Southern Hemisphere climate anomalies (Ethan C. Campbell, et al., Nature)

Indeed, the articles provided an interesting explanation for those odd polynya phenomena in Antarctica, but it was actually this intriguing image that really grabbed my attention.

Instrumented Seal, University of Washington. Credit: Dan Costa/University of California, Santa Cruz
Image: Ocean measurements were also collected by seals swimming under the sea ice with temporary satellite tags, showing normal water conditions in the years that did not have large polynyas.
Credit: Dan Costa/University of California, Santa Cruz

Yep, that’s a seal with an antenna on it’s head!

It turns out that the study used data combined from satellite images of sea ice cover, some robotic drifters as well as elephant seals outfitted with sensors.

What’s more, using seals wasn’t a one-off operation. It was part of a program that’s been operating for over a decade according to the Coriolis Operational Oceanography site:

Since 2004, several hundred seals have been equipped with conductivity-temperature-depth (CTD) sensors in the Southern Ocean for both biological and physical oceanographic studies. A calibrated collection of seal-derived hydrographic data is now available from Coriolis, currently consisting of more than 300,000 temperature/salinity profiles. — Coriolis

The Coriolis site also has more information about the program which includes a link to this article about a web portal named MEOP. As mentioned in the video, MEOP stands for the title of the program which is Mammal Exploring the Ocean from Pole to Pole, and the site provides access to an international database of validated ocean observations collected by marine mammals such as seals, sea lions, and even turtles.

You can find out more about the program here.
MEOP web portal : ocean observations by marine mammals (Argos System)

On my journey to learn how scientists have been strapping sensors to seals to find out about what’s going on under the ice in Antarctica, it was impossible to miss some stories about other methods they are using.

For example, here’s a story where an evolutionary biologist named Paul Cziko from the University of Oregon explains how they setup something called the McMurdo Oceanographic Observatory (MOO). Spoiler alert. This time it’s humans diving way down under the ice. Burrrr!

Yes, you really can go to the MOO site and listen in on some seals and ice for yourself.

After all of this stuff about seals, why stop with listening? Aren’t you itching to see some more?

Here’s a short 360° video from BBC Earth that takes you under an iceberg to visit with a crabeater seal along with some gentoo penguins before returning to the surface to share some other views and perspectives about Antarctica.

That was a nice view of a seal under ice, but now here’s an even better 360° video that get’s you up close and personal with an elephant seal on a beach.

So there you have it. The moral of this story is that you should be careful about what you click on, or you might find yourself on an unexpected virtual journey to learn about seals with sensors, and then end up spending an hour or more exploring the frigid waters under Antarctica.

In case you’ve got a few more minutes and the interest, here are links to two more very nice YouTube videos about the amazingly diverse and beautiful life deep under the Antarctic ice.
The Deepest Dive in Antarctica Reveals a Sea Floor Teeming With Life
Discovering Life Under Antarctica’s Ice

Finally, now that I’ve got you down here with me on this unexpected adventure in Antarctica, the trip wouldn’t be complete without some more penguins, right?

Here’s a 360° close-up view of a colony of some Adélies, chinstraps and gentoos — some of them are having a rough time, but nonetheless, they’re all still fun to watch (esp. the chicks).

Have a great weekend!

Find out more about Seals and Antarctica