Antarctica Is Melting:
Climate Destruction, Part II
Two weeks ago I looked at the arctic sea ice decline and at some of the native animals whose numbers are threatened because they depend on below-freezing temperatures, at least for a part of the year. The edge of the ice regularly retreats towards the North Pole during the summer months, but it doesn’t regrow all the way to its previous levels. Every year, the summer sea ice loss continues because of global warming.
When I did the research for this and the last article I realized that I knew very little about the polar regions of our Earth. For example, I wasn’t aware of the fact that their main difference is geographical: The Arctic is an ocean which is covered by a relatively thin layer of permanent sea ice, called the Arctic ice pack (which expands and shrinks every year), and is surrounded by land (Eurasia, Greenland, Canada and the United States). The Antarctic, or Antarctica, on the other hand, is a continent (well, I knew that, but had no idea what it implies). It is covered with a thick ice cap which is surrounded by a rim of sea ice and the Southern Ocean. The ice cap, or Antarctic ice sheet, is up to 3 miles deep and covers 97.6% of the continent or about 5.3 million square miles. The ice makes up 70% of all the Earth’s fresh water. By contrast, the ring of sea ice which surrounds it is salty, frozen sea water and rises to the surface because ice is less dense than water. Sea ice is typically less than 10 ft. thick and shouldn’t be confused with icebergs, glaciers, and ice shelves that float in the ocean but originate on land.
This distinction is important because the reason for the loss of ice in the Antarctic isn’t only warmer surface temperatures, the cause for melting sea ice in the Arctic, but also rising temperature of the ocean which causes icebergs to melt and erodes the ice shelves from below. This is particularly noticeable on the western side of Antarctica where the Thwaites Glacier is located, the widest glacier in the world, larger than the size of Florida. It is nicknamed the Doomsday Glacier because of its fast and increasing ice loss. If it would totally collapse, global sea levels would rise 25 inches! While this won’t happen anytime soon, a scientific study published on October 23 in Nature Climate Change concludes that it may be too late to reverse the trend, even if the Paris 1.5 °C and Paris 2 °C scenarios could be reached – which looks unlikely. Have a look at the NASA Sea Level Projection tool.
Thwaites is a cork in the bottle of West Antarctica. Its vast size and central position mean that its collapse could trigger a reaction across the entire West Antarctic Ice Sheet. It’s possible this happened around 125,000 years ago, when sea levels were about six to nine meters higher than today. West Antarctica won’t fall apart overnight. It might take a few hundred years. But if it does happen—as many researchers fear it will—it will redraw global coastlines.1
Unusually warm ocean currents are melting the ice. Those currents are driven by shifting wind patterns: stronger winds displace cold surface water, allowing deep warmer water to rise up and pour over the continental shelf into the marine basin beneath the glaciers. The winds, in turn, respond to one thing: changes in air temperature. And those changes are caused by greenhouse gas emissions.
According to Ted Scambos, a glaciologist at the University of Colorado Boulder, the only way to really stop the rapid ice melting would be not just to cut levels of planet-heating pollution but also to “remove some that has already built up.” This will be “a real challenge,” he told CNN on October 23.
Maybe I got carried away a little; I bet this is more than you wanted to know, because it’s rather depressing. And yet – those are the facts.
But to make us feel better, I won’t continue with some disturbing numbers of declining penguin populations but rather focus on these adorable animals themselves, at one of the 17 to 20 species. Look at the Emperor Penguins and their chick vocalizing in Antarctica in the little video above, from Christopher Michel (licensed under the Creative Commons Attribution 2.0 Generic license.)
Emperor Penguins are the largest of all penguin species found today; some may grow to 50 inches high and can weigh close to 90 pounds. They also belong to the largest birds, although they can’t fly. Instead, they can dive – the deepest recorded dive was 1,755 feet, and the longest recorded dive was nearly 32 minutes. Isn’t that incredible!
Actually, almost everything about their lives sounds incredible. Just think of the harsh conditions of their environment: temperatures can reach -58°F, wind chills can go down to -76°F, and winds can reach 125 miles per hour.
And they breed during the darkest, coldest season. The female lays one egg late in May or early June, at the beginning of the Antarctic winter. She then takes off, hunts for food, and leaves the incubation to the male. He faithfully protects and warms his offspring: for over two months he holds the egg on the top of his feet, with a layer of skin draped over it for protection (known as brood pouch). He doesn’t eat anything during this time and loses almost half of his body weight!
The colony has an ingenious tactic which allows them to stay warm: 5,000 or more birds huddle closely for warmth, and they shuffle around – so each one takes a turn to stand on the outside where it is cold, but never for long. I believe bees use the same method to keep their hive warm in the winter.
Mom comes back just when the fluffy chick bursts out of the egg. Her belly is full, and she can regurgitate to feed her baby, while Dad finally is free to search for food for himself.
The mothers protect their young chicks inside of their own brood pouches. When the Antarctic summer arrives, in December, the ice begins to break up and open water appears just in time when the young Emperor penguins are able to swim and fish on their own.
Just like polar bears, emperor penguins’ lives depend on solid ice. Melting sea ice threatens their survival and reproduction. In October of 2022 they were granted protection under the Endangered Species Act. Let’s hope this will help.
Climate change is unnerving - there are signs everywhere...some subtle, and others rather obvious - like your mention of what's happening in Antarctica. And here, too, the glaciers are melting at an alarming rate...and just this morning, I saw a butterfly in the garden - a creature that certainly should not be around in mid-November.
Thank you Jessica, that was good to read, all around, from the bad part onward.