Why Greenland's glaciers will melt much more quickly than anybody thinks

[benburch]

I believe that the current human-caused (largely American-caused) global warming will melt the glaciers of Greenland much quicker than anybody now believes, possibly in a couple of decades.

Here is the reason; Not only have we put enough greenhouse gases into the atmosphere to raise the air temperature worldwide, but we have also been putting massive amounts of dark carbon particulate matter from the burning of coal and oil, and a lesser amount of soil dust from mechanized agriculture into the air.

Over the 200 years of the Industrial Revolution that particulate matter has been washed from the air in precipitation.

In Arctic areas, including Greenland, that precipitation takes the form of snow.

Now, a picture of the Greenland glacier likely looks like pure white snow because the amount of black carbon in any given snowfall is insufficient to make the albedo (reflectivity) of the snow appear to be any different from a normal snowfall, but every layer of snow that has been deposited in the last 200 years has its own burden of black carbon.

As warming begins to melt the snow burden, and the water evaporates or runs off, its burden of black carbon largely remains in place.

The effect of the dark carbon is to lower the albedo of the snow and therefore to accelerate the heating of the snow, and the layer of air immediately above the snow, by the sun.

This process "snowballs", that is, creates a positive feedback loop in which the surface layer of the snow progressively darkens, and melting happens more and more quickly.

Think of how a dirty snowdrift melts; The dirtiest parts melt MUCH quicker than the relatively clean parts.

The Greenland glacier is a huge dirty snowdrift.

I believe it will melt much more quickly than anybody imagines, and that the flooding of coastal areas will occur much faster than anybody now imagines.

Comments welcome.

[starmaker]

1. Same is true for Antartica

and probably every glacier worldwide

[htuttle]

2. Also, snow and ice lose structural integrity long before they are 'melted'

Big chunks will start collapsing along existing fissures into standing water and melt all the faster. Those glaciers will turn into waterslides and ice-filled rivers long before you'd expect them to melt due to the temperature alone.

[BoneDaddy]

3. Siberia

Just read last week that the Siberian peat bogs are releasing massive amounts of methane into the air as the ice above them are melting. This will continue to add to the amount of greenhouse gases that will continue to push us towards a drastic climactic shift in the near future.

Lovely.

[mtnsnake]

4. Yeah, but our president doesn't agree with that,

so who am I to believe...the scientists who have researched this and who make so much sense, or the imbecile in the white house who isn't convinced there is any such problem.

[The Traveler]

5. What you describe is probably a "second order effect"

Not a big driver. But ... the whole warming process seems to be going faster than expected. And now that the Siberian permafrost is melting, the process will accelerate. Apparently, as the permafrost melts, scientists expect methane trapped in the frozen bog will be released. Methane is 20 times more efficient than CO2 as a greenhouse gas ...

Obviously, we are triggering "feedback loops" both great and small. Things are difficult to predict now as the chaos of the system rises. Imagine a pencil poised on its tip. We know it will fall ... but we cannot predict its final orientation. A new equilibrium will be reached, but we cannot know what it will look like.

"The Day After Tomorrow" scenario is a possibility ... low probability. Alas, it may be one of the less disastrous of possible outcomes.

[rwork]

6. I hope to see

Rush Limbaugh and Jim Inhofe frogged marched before a court.

[MadHound]

7. An interesting theory regarding the melting of the Greenland ice sheet

And that is that all of that fresh water released into the ocean will dilute the salinity of the Gulf Stream current to the point where the GSC will no longer be able to make the return journey from the North Atlantic to the Caribbean, thus shutting down the GSC. Shut down the GSC and the land masses in the North Atlantic will experience an ice age, thus renedering Northern Europe, including England, along with northern North America into an area much like North Alaska, and this will precipitate another Ice Age worldwide. Some very valid science has gone into this theory. And the really scary thing is that ice core data indicates that this scenario could happen quite quickly, in the space of as little as ten years after the salitiny first starts to dilute. Guess what, latest salinity data shows that right now, the salinity of the Gulf Stream Current is lessening.

So rather than global warming, we might want to start preparing for a global Ice Age. Bundle up!

[im10ashus]

10. I totally agree.

Most people associate global warming with higher temps. That would be true in many parts of the world, but the salinity levels of the ocean have been a main concern for scientists for sometime. What was the name of that Jake Gyllenhal movie where this exact scenario happened? It may not be too far removed from fact after all.

[Coexist]

11. the Discovery Channel had an excellent program on this

it was fascinating and scary.

[Ganja Ninja]

8. Isn't a large part of Greenland also below sea level?

Seems to me I heard that somewhere. The ice is sitting on ground that is below sea level and as it melts could also start to float away from the land mass.

[benburch]

14. Yes...

It is pushed down by the weight of the ice. When the ice melts, it will float up again, very slowly.

[zalinda]

9. So, what can we, the little people do?

I can't drive any less than I do now. I've always combined trips, I could never see wasting gas, even when it was less than $1 a gallon. I want to buy some land and do some energy projects, but I can't manage that myself, I'll need a partner to help. So that is put off for awhile. Any suggestions?

zalinda

[Boomer]

16. Prepare for the worst

If you have any yard space at all, start gardening. Even if you don't have a yard, try container gardening in any free space. It takes YEARS to learn how to grow your own food, so start now if this is an unacquired skill.

Keep a well-stocked food larder. I'm not talking a weekend's worth of goods, rather enough staples such as dried beans, rice, flour, canned veggies and meats to last you several months or longer. And don't forget large quantities of water and water purifying tablets. Keep the larder fresh by using the oldest items and restocking.

Maintain an emergency stock of batteries, flashlight, first-aid, etc. We bought solar or spring-powered radios and flashlight for quite reasonable prices on eBay. Which means we can lose power and still hear the news.

Buying a gun would probably be advisable. We haven't taken that step yet. Not sure we ever will. But we're aware that if we ever DO need our emergency supplies, the inability to protect ourselves may make survival a moot point. After all, those who don't prepare can just take from others who do.

[Gabi Hayes]

12. much scarier is the melting permafrost in Siberia....the size of Germany+

France!

it sits over a gigantic peat bog, which, when exposed, will fill the atmosphere with methane, which is TWENTY TIMES worse a greenhouse gas than CO2.

it's already started, and scientists think there's no way to stop it, which will start a very vicious cycle of more heat in the atmosphere, more permafrost melt, more methane, more heat, more melt

can you say "Day After Tomorrow" (a truly rotten movie, of course, but it at least put out for the public one of the possible scenarios)

a better exposure to this, and very well written, too, is Forty Signs of Rain, by Kim Stanley Robinson, an author who would be MOST at home at DU.

[Toots]

13. Not sure that is true at all. The dirt acts as an insulation barrier

The dirt acts like an insulation blanket over the ice and snow. I would say the dirty ice melts much slower than clean ice. However that said the ice is still melting at a record pace and I believe we have achieved the point of no return.

[benburch]

15. Try an experiment this winter for youtself.

Take a snow bank with a southern exposure and some crushed charcoal. Treat half with a dusting of the charcoal, and monitor it through a few sunny days.

I think you will find that the treated half melts MUCH quicker.

I've done this intentionally to get rid of snow after huge snowfalls.

[pitohui]

17. well enjoy them now

like the tourist mags say, if you want to see glacier nat'l park or the glacier-tipped mtns of the andes, see 'em now, if you wanna see vanatu or the marshall islands, see them now

they won't be here in 20 yrs

apparently it's too late to turn the tide so i don't know what else we're supposed to do abt it altho i feel the westernized nations (not just the usa) will be & should be obligated to provide new territories to the displaced marshall islanders & the rest