Spring is in the air in Antarctica, and NASA scientists are keeping a close watch on a huge crack in the Pine Island Glacier that’s looking ready to pop. If (or when) it calves, it will produce an iceberg the size of New York City — the largest sea level rise contributor from Antarctica, according to NASA’s Dr. Kelly Brunt.

Antarctic glaciers do this sort of thing every now and then, so that’s not what makes this particular break interesting. As Brunt explains in the new video below, if cracking glaciers can be compared to breaking fingernails, this Pine Island crack is like a nail that has broken below the white — back where shouldn’t break and where it really hurts. She explains it well for NASA’s Operation IceBridge:

This Pine Island Glacier event might seem to somheow contradict recent reports of record sea ice extent around Antarctica. This information has been misused by climate science denialists to argue that while the Arctic is warming and losing sea ice, it’s okay because the Antarctic is making up for it. Wrong. Here’s the real story from the National Snow and Ice Data Center. I have highlighted the key parts:

“First, climate is warming over much of the Antarctic continent, as shown in several recent studies (e.g., Chapman and Walsh, 2007, Monaghan et al., 2008, Steig et al., 2009) and is related to Pacific Ocean warming (Ding et al., 2010) and circumpolar winds. Both warming and ozone loss act to strengthen the circumpolar winds in the south. This is due primarily to persistently cold conditions prevailing on Antarctica year-round, and a cold stratosphere above Antarctica due to the ozone hole. Stronger winds generally act to blow the sea ice outward, slightly increasing the extent, except in the Antarctic Peninsula region, where due to geography, winds from the north have also increased, pushing the ice southward. Thus, sea ice extent near the northwestern Antarctic Peninsula continues to decline rapidly, while areas in the Ross Sea and the southern Indian Ocean show significant increases (Stammerjohn et al., 2012). Circumpolar-averaged sea ice extent changes nearly cancel each other out for all months of the year (Parkinson and Cavalieri, 2012). This winter, atmospheric conditions were near average overall, with roughly equal areas of cooler and warmer air temperatures over the sea ice.”

SLIDESHOW: Climate Tipping Points

The bottom line is that Antarctica isn’t the Arctic. It’s a continent at the bottom of the world — the highest continent, too. It’s surrounded by water, while the Arctic is a sea at the top of the world, surrounded by land.

It doesn’t take a rocket scientist to understand that despite being polar, they are extremely different climatic beasts. So we need to watch these places individually and we should take notice when glaciers break off above the quick.

Photo Credit: NASA / Jim Yungel