Antarctica Is Melting Three Times As Fast As a Decade Ago (nytimes.com)

An anonymous reader writes: Between 60 and 90 percent of the world's fresh water is frozen in the ice sheets of Antarctica, a continent roughly the size of the United States and Mexico combined. If all that ice melted, it would be enough to raise the world's sea levels by roughly 200 feet. While that won't happen overnight, Antarctica is indeed melting, and a study published Wednesday in the journal Nature shows that the melting is speeding up. The rate at which Antarctica is losing ice has tripled since 2007, according to the latest available data. The continent is now melting so fast, scientists say, that it will contribute six inches (15 centimeters) to sea-level rise by 2100. That is at the upper end of what the Intergovernmental Panel on Climate Change has estimated Antarctica alone could contribute to sea level rise this century.

"Around Brooklyn you get flooding once a year or so, but if you raise sea level by 15 centimeters then that's going to happen 20 times a year," said Andrew Shepherd, a professor of earth observation at the University of Leeds and the lead author of the study. Even under ordinary conditions, Antarctica's landscape is perpetually changing as icebergs calve, snow falls and ice melts on the surface, forming glacial sinkholes known as moulins. But what concerns scientists is the balance of how much snow and ice accumulates in a given year versus the amount that is lost.

Comments

Yes, The World Is Returning To Normal

[ComputerGeek01]

I hate how many otherwise intelligent people completely misunderstand global warming. Although people are contributing a fair amount to the rate at which we are warming up, this planets default temperature is much MUCH higher than what our species is comfortable with. Guess what? If you are reading this, you were born during an ice age: https://en.wikipedia.org/wiki/...

Re:Yes, The World Is Returning To Normal

[hipp5]

I hate how many otherwise intelligent people completely misunderstand global warming. Although people are contributing a fair amount to the rate at which we are warming up, this planets default temperature is much MUCH higher than what our species is comfortable with. Guess what? If you are reading this, you were born during an ice age: https://en.wikipedia.org/wiki/...

So what? From a human perspective (arguably the thing that matters most to you and me), normal is what we have now, and any deviations from that are going to cause us pain and suffering. It might be inevitable, but it's absolutely in our best interest to have it happen as slowly as possible. Cities, industries, and crops are where they are; moving them or hardening them is gonna be hella expensive and would be better done over long periods of time. Not to mention that really fast rates of change could destabilize the very fabric of our societies. That's nice that we're in an "ice age", but it means diddly squat to whether or not we should be trying to reduce our contribution to climate change.

Re:Yes, The World Is Returning To Normal

[jellomizer]

The Rate of global warming is the biggest issue. Just like falling it is your rate of speed that you hit the ground is what will kill you.

The world isn't ever "Normal" it is always in flux, but if we change it too much a lot of things can die.

Re:Yes, The World Is Returning To Normal

[Solandri]

So what? From a human perspective (arguably the thing that matters most to you and me), normal is what we have now, and any deviations from that are going to cause us pain and suffering.

In this context, "normal" means the difference between "We need to do everything we can to stop climate change" and "Climate change is inevitable, so let's get busy moving our infrastructure away from the coasts." Opportunity cost is measured against the possible alternatives, not against what you used to have in the past.

If climate change is man-made due to our emissions, then we need to do what we can to stop it or slow it down by reducing our emissions.

If it's natural, then changing our emissions is pointless - it's going to happen no matter what we do about our emissions. We need to stop worrying about emissions and start worrying about moving our infrastructure to be able to survive the change. Slowing it down only increases the time we have to move our infrastructure, it doesn't alter the fact that we need to move it. So changing our emissions then only becomes worthwhile if the extra time to move our infrastructure would reduce the overall cost to move it. In fact speeding it up may actually be preferable since if the change is visible in the short term, it elicits a sense of urgency that gets people to prepare. If there's no visible change, it breeds complacency and skepticism, and we end up doing nothing about the problem. The long-term changes just become stories your great-grandfather told you and what you read about in history books, easy to dismiss as fabricated.

It might be inevitable, but it's absolutely in our best interest to have it happen as slowly as possible. Cities, industries, and crops are where they are; moving them or hardening them is gonna be hella expensive and would be better done over long periods of time

You're confusing a rate with an amount. While spreading the cost of a move over more years decreases its cost per year (a rate), it doesn't change the total cost of the move (an amount).

Our infrastructure's lifespan is on the order of 50-100 years. Most concrete and steel structures wear out and need to be refurbished or replaced within that timeframe. So that's the timeframe within which a move will have the lowest total cost. If you go faster, you end up abandoning infrastructure which still has usable lifespan. If you go slower, people (both the complacent and skeptics) end up building new infrastructure in the areas you're trying to abandon long-term.

Re:Yes, The World Is Returning To Normal

[DarkOx]

f you're so stupid that you think protecting the environment will sacrifice the well-being of your children, then your children would be better off if you slit your own throat.

No see the difference between you me and you apparently is that I actually understand ecology, economics, and don't make purely emotional decisions. Protecting the environment really comes down to a function of people per area. There really isn't any bigger driver of environmental impact. Yes I want a country where there are large wildreness areas where my kids can enjoy. Where we maintain a little bio-diversity. Where we they can go hiking and fishing etc. Guess what carbon foot print has very little to do with that.

Population has EVERYTHING to do with it. The biggest threat to our environment today in the United States is IMMIGRATION! Don't care if your Republican, Democrat, other. If you not in favor of curbing immigration you are on the wrong side of the environmental issue whatever other policy you might support.

how terrible.

[fish_in_the_c]

People who believe that God created the world and expects us to act as care takers of His gift for the next generation of humanity should be shocked and appalled and take every responsible action to ensure the gift we have been given by God is preserved and passed down to the next generation.

However I can't think of any reason that would inspire action for those who have no faith because the results of any action on this matter for or against are unlikely to have any effect beyond our lifetime.

That brings the next real question, how can we motivate people to action , how can we ensure that action does not unjustly disenfranchise the poor.

Re:how terrible.

[amiga3D]

To make any difference requires a drastic change in modern lifestyles. I mean massive and complete change in how modern man lives. Given that you can't convince a majority of people to give up their cars, air conditioning, beef and hundreds of other things that would have to go plus do something about population growth I don't see any real solution. A global thermonuclear war might solve it but that brings it's own problems. Without a world government exercising dictatorial and draconian laws we're on a course for a hotter planet. That or maybe technology will save us. People watching GW advocates like Gore travel the world in a private jet and living in a mansion the size of a small town aren't going to give up modern luxuries.

Alarmist much?

[LynnwoodRooster]

The NY Times article has this big graph showing an accelerating downward trend starting in 1994. Yet NASA says that Antarctica has been gaining ice from 1979 to 2015. So which is it?

And when you look at the confidence intervals (2720 +/- 1390 - the window is LARGER than the estimate!) you start to get an idea that this is a "well, we don't know but... FLOODING!". I'm sorry, if any engineer or researcher working on my team came and said "I believe the correct value is 50, with a tolerance range from 0 to 100" I'd send them back to the bench after a good chewing out or they'd be sent out to the street...

Re:Alarmist much?

[njvack]

Okay, I'll bite.

The two studies do indeed contradict each other. They use different methodologies. The Journal of Glaciology "Antarctica has been gaining mass" presser linked there (here's the paper, I believe) appears to use altimeter measurements alone, while the Nature paper uses a combination of altimeter data, gravimetry, and the "input-output" method which appears to estimate glacier melt and snow accumulation more directly. (You may have paywalls, I'm at a university.) Which paper to trust? I'm not a glaciologist, I can't answer that.

And yeah, the confidence intervals in the Nature paper are kind of wide. Measuring the mass of ice on a sparsely-populated continent is actually pretty hard, I suspect. But an estimate at either end of the CI still means you're losing a bunch of ice. With your engineer... I'd hope your response would depend on what question you were asking. Are 0 and 100 both numbers you can deal with? Is your acceptable range 40 – 60, or -1000 – 1000? Raw numbers are meaningless without context.

The main takeaway from the two papers are kind of similar, though. There's a LOT of ice in Antarctica. Sea levels are, right now, measurably rising — I mean, "FLOODING" is happening in coastal communities now. Dealing with it is really expensive. If Antarctica's ice melts faster, we'll see more flooding, sooner. If your argument is "increased global temperatures will increase Antarctic snowfall enough to more than offset faster melting," sure, make that argument, but the scientist in the NASA press release you linked to says the exact opposite:

If the losses of the Antarctic Peninsula and parts of West Antarctica continue to increase at the same rate they’ve been increasing for the last two decades, the losses will catch up with the long-term gain in East Antarctica in 20 or 30 years -- I don’t think there will be enough snowfall increase to offset these losses.