Cold freshwater from melting Antarctic ice shelves is insulating sea ice from the warming ocean.

Sea Ice In the Southern Ocean
Sea Ice In the Southern Ocean Richard Bintanja

Climate change is expanding sea ice in Antarctica, a paradoxical finding that appears to be the result of melting glaciers, according to a new study. As freshwater glaciers melt, cold water sinks into the ocean, keeping the sea colder than it would otherwise be.

The fresh water is less dense than seawater, so it floats on the top layer of the ocean, which in turn stays cooler. That makes it easier for the seas to freeze again in the Antarctic fall and winter, scientists say. This negative feedback is expected to continue, they added.

Sea ice levels in Antarctica are a major part of ongoing climate change research. Scientists have been puzzled as to why sea ice cover is rising in the southern ocean, while ice in the rest of the world is clearly melting. This study sheds some light on the question.

Richard Bintanja and colleagues at the Royal Netherlands Meteorological Institute used a climate model to show how sea ice expands during fall and winter in the southern hemisphere (our spring and summer). Along with insulating the seas and safeguarding sea ice, this cool, fresh surface layer could also reduce snowfall on the frozen continent. That's because cold air can hold less moisture than warm air; a cool layer would be less likely to be sucked out of the ocean to fall again as precipitation.

There is an alternative explanation for Antarctica's growing sea ice: It could be the result of changing wind patterns, as the BBC notes. But that, too, is a result of changing climate patterns.

The findings appear this week in Nature Geoscience.

Sea Ice Near Antarctica
Sea Ice Near Antarctica:  Richard Bintanja

15 Comments

Until Al Gore says it, we can't believe it.

Yes as I put ice cubes into my glass, the melting ice does add cold water to my drink, temporarily cooling the drink.

As global warming warms the planet over all, as it can cause an growing abundance of melting glaciers to journey south, I suspect it might cause 'temporary' cold weather breezes on the environment, confusing the issue of global warming.

Overall, the ice in my glass will finally melt and yes the drink will eventually warm to room temperature.

But hey, I am just guessing here.. lol.

Just an other example of the fact that there are literally countless linked feedback scenarios that are all acting to keep climate in check.
Stan

The earth climate is changing as it always has and man has very little to do with it. Any claims to the contrary must prove that variations we observe are somehow unnatural. Climate alarmists completely gloss over this requirement, because they want to sell us natural variations as somehow supernatural. This is not to say that we cannot spot some human effects on our climate, such as the "Urban Heat Island Effect."
These effects are small when compared with the vastness of our oceans and atmosphere.
Climate simulations are not legitimate evidence of anything beyond a fertile imagination.

@PriklyPete

I agree with you. The world has gone through numerous warming and cooling periods, interglacial and glacial periods as well as stadial and interstadial periods. Because human history is relatively short we've been alive in a relatively stable time period. Instead of being so anthropocentric and scaring everyone into believing that we're the cause of global warming why not just look at the way the Earth has worked in the past?
After serious warming periods the Earth cools down. It's all a part of cycles humans may never compete with. The Thermohaline circulation, the Milankovitch Cycles, Solar Cycles, Tectonic movement and Volcanic eruption. So many things that affect the Earth far more than humans.
I'm not saying it isn't happening, I'm saying it's not our fault and we should learn to live with the future slightly warmer climate and more importantly the glacial period which will follow.

This wouldn't have anything to do with the influx of fresh water into the oceans from the Polar Ice Caps initially melting, thus causing the major currents ie the Gulf Stream, to be unable to carry warmer waters North and vice versa for the major ocean current that accomplishes the same thing for the Southern Hemisphere?

If you look back at every major ice age (even the minor ones) it would appear that an initial warming takes place first, forcing the major currents to stay near the equator.

What to take away from this:

1. The amount of ice disappearing is exaggerated, as much of the glaciers of ice that break off into the water still survive as ice flows. We haven't lost as much ice as we thought.

2. We have two giant ice mirrors on planet earth... at the least effective locations possible; the poles. Ice floating in the water further north means that those reflective properties are acting on latitudes that receive more sunlight, as their surface has a steeper angle between that an incoming light.

Seems like yet another self-regulating, negative feedback mechanism not included in the computer models. Yet another article further weakens the AGW case. Keep them coming Popsci.

dmidify,
Global warming, dumping of fresh water into the gulf, temporary stopping or slowing of the gulf stream, temporary global cooling, the ice continues to melt and were back to global warming with nothing to stop it.

Anything. Absolutely anything to cling to the biggest scam in modern history.
Fresh water is heaver than salt water so it sinks.
Play again.

I'm pretty sure that Anylcon is robot... Who else posts on almost every single article without actually adding anything useful?

I think this has more to do with government research grant money than science. One of the current religious beliefs of the Federal government is that global warming is real, therefore if you want research money, you must knee and kiss that ring.

great comments all...
robot.. not so much :)

Sorry, Lazlo. Fresh water is less dense than salt water. You can test this at home. Fill a glass with water and red food coloring and add a whole bunch of salt to it. Then fill another glass with fresh water and blue food coloring. Cover the blue glass with a thin sheet of rigid plastic (or not rigid if you're a ninja) and flip it upside down, holding the plastic firmly so you don't make a huge mess. Place the blue glass covered in plastic over the red glass, the remove the plastic slowly. The two will stay separate. If you repeat the experiment, but put the fresh water on bottom, they will mix because the salt water will sink.

Earth's magnetic field funnels particles to the poles, thus the northern and southern light shows you see. The poles also reflect the most sunlight. More Antarctic ice will definitely have an effect on the ocean currents, which will affect the weather around the world.

Fresh water has a greater specific heat value than salt water. This would mean a higher heat transfer rate from the atmosphere to the surface layer of fresh water. The result would be warmer ocean surface temps, not cooler surface temps.


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