Moss on melting ice with Antarctic mountains in the background.

Antarctica is changing, for good. This is what scientists say it will look like by 2100

Only a tiny part of Antarctica – less than 1% – is permanently free of ice.

Yet this is where most of its unique plants, mosses, lichens, algae, invertebrates and animals manage to survive.

But everything is changing. By the end of the century, thousands of square kilometers of permanently ice-free habitats will open up on the continent, even under moderate climate change.

In general, growing seasons will lengthen, more precipitation will fall as rain, more fresh meltwater will be released, average temperatures will become milder, and extreme weather events, as elsewhere, will likely become more intense.

Put it all together, and you have a transformation of parts of the world’s most intact environment.

The researchers have therefore painted a picture of what it will look like, publishing their analysis in Global Change Biology.

Penguin walk?

“Some species of penguins will win, but others will lose,” said co-author Justine Shaw of Securing Antarctica’s Environmental Future, Queensland University of Technology.

Gentoo penguins are already advancing to new habitats as the ice recedes in West Antarctica, as are Adélie penguins on Beaufort Island and king penguins in the subantarctic part of South Georgia, according to the analysis.

This is a very important point.

Antarctic soils buried under ice for millennia are generally nutrient-poor and unable to support much life.

Penguins surrounded by snow and grass.
Colonies of king penguins are advancing as the ice recedes over subantarctic South Georgia.(Getty Images: elmvilla)

But penguin poop, or “guano,” is packed with nutrients like nitrogen and phosphorus, as well as trace metals.

In this way, penguins act as ecosystem engineers – as they move through newly discovered habitats, they help prepare the ground for things like plants, lichens and mosses to grow there. install.

So much so that the growth of vegetation on newly exposed ground can betray the location of old penguin colonies, which existed during previous periods of warming.

Scientists can use soil analysis to confirm these locations.

“You look and say, ‘Why is there a big moss bed here? ‘” Dr. Shaw said.

“The ice can melt and expose an old colony of penguins, where you have nutrients locked in that soil.”

But it’s not all good news for the penguins. Some, like the emperor penguin, depend on sea ice for breeding and feeding.

“The emperor penguin looks like it’s not coping well with climate change. It doesn’t happen anywhere else in the world.”

Will we see trees in Antarctica?

There are currently only two species of flowering plants native to Antarctica – the Antarctic Hairweed and the Antarctic Pearl.

Both are thought to have colonized Antarctica multiple times over tens of thousands of years, via wind and animals from South America.

A patch of green hair grass.
There are only two flowering plants native to Antarctica, although the threat of weeds taking hold is increasing.(Getty Images: Gerald Corsi)

But if penguins and shorebirds prepare more ice-free areas for vegetation, could we see trees moving onto the mainland?

“Certainly not in our lifetime. We don’t have any trees on the subantarctic islands yet,” Dr Shaw said.

It’s not just harsh conditions that keep trees at bay.

“The Southern Ocean is a pretty massive barrier,” she said. The seeds should remain viable after crossing this vast expanse of salt water to establish themselves in Antarctica.

But some non-native plants and invertebrates have managed to do this. So how did they do it?

“Where we’ve had weeds and invasive species before in Antarctica is where people have been,” Dr Shaw said.

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