Sea Levels Rising: What You Need To Know

Q. Dear Umbra,

I'm a bit confused about the possible rise in sea level that may be caused by global warming. I know that in general water expands when warmed, and that is one cause of sea level elevation with respect to global warming. The larger cause for alarm seems to be the melting or collapse of the polar ice caps. I recently read an article that warned that Antarctica, which stores 70 percent of the world's fresh water, could lose the Ross Ice Shelf (a block of ice the size of France) suddenly and without warning and "that its collapse would make sea levels rise by at least 5 meters, with other estimates predicting a rise of up to 17 meters." My question is how quickly would such a rise register?

Saor
Mill Valley, Calif.

A. Dearest Saor,

I got all swept up and joined your completely logical confusion. If ice shelves collapse, when can we expect the swamping wave? Happily, this is incorrect thinking. Many thanks to the good people at Environmental Defense for straightening out my confusion. My mind now runs clear as a glacial river to the sea of climate comprehension.

Read the whole story here.

Comments

[oneofsixbillion]

Remember folks, everything is interconnected, melting ice can also effect our oceans currents which drive our weather systems resulting in climate instability.

[tc399]

Actually, there may be more than one Earth Scientist present., RT. But thank you for the correct information. I was somewhat surprised at the Umbra post., especially this:

"We are warming the atmosphere by increasing greenhouse gas concentrations, the oceans are absorbing large parts of this warmth, warmer water takes up more space, hence the global sea level is rising."

[RTIII]

Well, the primary cause of sea level rise is melting ice that's been supported by land. All other causes are temporary in nature. And, I suppose, over a long enough time-scale, even the ice-melting based change is temporary! However, there is truth to the statement that warmer water takes more space.

The sea surface is not uniform across the world's oceans. Tides, local gravity anomalies, and even prevailing wind play a role. So, too, do smoke plumes and volcano fallout - specifically because they change the amount of sunlight that falls on the surface and therefore changes the waters temperature, over time - among yet other causes.

...Thanks for noting that there may well be other Earth Scientists posting here - I hope so! I didn't mean to sound territorial or anything. I'm just a regular contributor and I've never noticed another that mentions any similar background...
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[tc399]

I rant about politics for the most part, but Ken Takahashi and I play in the ES band.

Warmer water does take a bit more space, but I'm sure you were not supporting the view that a sea level increase of thirty feet in an unspecified but non-geological time frame might be due to water becoming warmer from reflected radiation.

I wish I could get Robin Bell in here. She shares the top tier of ice shelf research.

[ohiomark]

My home is about an hour south of Lake Erie. I can't wait for beach front property.

Get over yourselves Libs, you can't change or control the climate.

[RememberTheAlamo]

Hi ohiomark,

I agree with you, but you must remember the rules of this blog . . .

(1) Global Warming is something like the 6th law of thermodynamics (indisputable)
(2) All energy consumption, by conservatives (i.e.- familes) is real bad
(3) CO2 emissions, if you carry a "CO2 credit" card, are very good
(4) Gas prices are not high enough
(5) Removing status symbols (like SUVs) would be very VERY good.
(6) Trusting unproven technology is "refreshing"
(7) Oil, in all it's forms, is considered pure evil.
(8) Ideas which drive families from suburban living to urban living will get you extra points.
(9) Hybrids are considered really cool (I am not sure if I am allowed to use that word again?)
(10) Everything electrical or chemical is favored over solutions using mechanics or fluids.
(11) Oil companies are the source of all evil
(12) Wind and solar power are economical today
(13) and recently discovered that kinetic energy is no longer (1/2)MV^2
(14) Also . . . only the government can solve our energy problem . . . since the rest of us are "mindless"

. . . and I hope I got that right this time!

Saving you the learning curve!
Yours
Texas Proud

[oneofsixbillion]

Stop spreading the "hate" please. It gets us know where. This is not a partisan issue.

Yours,

American Proud

[MGhamma]

ohiomark, dude! DUDE!! Do you ever listen to yourself? Do you ever try to think before you post? HOLY TOLEDO!!

[RealityBaseCamp]

ohiomark mistook fresh for salt water:

"My home is about an hour south of Lake Erie. I can't wait for beach front property. Get over yourselves Libs, you can't change or control the climate."

Whoa... He thinks somebody is claiming the Great Lakes will rise when the oceans do? I hope he doesn't do his own plumbing.

[ohiomark]

It's called "illustating absurdity by being absurd".

Besides, using the logic of the left, all the melting ice at the North Pole will not just melt into the oceans, they will melt into the rivers and lakes of Canada, which feed the Great Lakes. Also, when the next "ice age" comes, which is the next climate scam from the left, Canada and half of the United States will be covered by a giant glacier.

[RTIII]

I pondered that for a moment - it occurred to me that perhaps there will be a back-flow of water into the Great Lakes? I didn't follow up to see what the elevations up the St. Lawrence are. And, I figured he's very unlikely to listen to anything I have to say, so what's the point?
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[RTIII]

Change. yes, control, no.
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[ohiomark]

What's the difference?

If we have the ability to change it, then we have the ability to change it back.

Here's a hint: We don't!!!

[RTIII]

PART II

What's REALLY going on is that Ross is a gentle slope of land down which ice flows into the sea. The seaward end is floating and the opposite regions are well on land, and inbetween, the region where the kilometers thick ice transitions from being supported by land to water , the bottom is lubricated by meltwater and the more melting that occurrs, the less friction and the faster the ice moves. The moving ice, in turn, rises local sea level, further lifting the ice off the land, which reduces friction even more - and so the ice moves faster. Its a positive feed-back loop.

No one on earth can tell you the real timeline - NOBODY knows and anyone who pretends to is a liar. I know, I've been in the room when the worlds greatest experts debated this very fact.

Additionally, many seem to overlook that as world sea-level rises, a large volume of ice that sits on shorelines will also met and contribute to the total.

Expect between 30 to 60 feet in the next 30 or so years - a little over 180 feet is _possible,_ but would require it all to melt.
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[TimmySlagle]

RTIII just said it all:

"No one on earth can tell you the real timeline - NOBODY knows and anyone who pretends to is a liar ... Expect between 30 to 60 feet in the next 30 or so years "

By your own admission:

LIAR!

[RTIII]

Dear Timmy,

being disingenuous again, I see.

You know I didn't say what the real timeline is, I merely said what I expect - and I gave a pretty big range.

Now, don't you go calling people names to try and prove points - it just goes to show you haven't any argument worth making. And if you make a habit of it, you won't have any friends when you grow up.

Run along now and find someone to argue with who you at least understand.
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[RealityBaseCamp]

PLUS, it occurs to me, the part between the fully-floating and on-land sections is partly *out of the water* (unless it's a very smooth slope and never drops off away from "shore"), and is hanging above the water. Any area that breaks off would go from its present state to fully 90-ish % submerged. Has anybody calculated how much water could be displaced if whatever amount of ice that isn't already floating collapsed, went into the water all at once, and sank to whatever extent it could? There was a technothriller novel that had somebody doing that with a nuclear weapon, but the point of that plot was to unleash a killer wave and benefit from it in whatever way villains do. It wouldn't be near the total potential rise, but I wonder how much that alone would amount to?

When that site said, "But ice shelves are already in the water, so their detachment and disintegration does not add any mass to the global sea volume in and of itself.", they left out the part that isn't already in the water. And they said "collapse" doesn't actually mean "collapse." Huh?

[RealityBaseCamp]

NL207 said, in part:

"The Salient point is that the Ross Ice shelf is already floating in water.
source: http://en.wikipedia.org/wiki/Ross_Ice_Shelf "

I stand corrected on that one. More plastic than I thought.

[RTIII]

P.S.

My statements aren't just guesses; this was my "take-away" from a very well attended meeting at JPL of the world's Ice researchers - about 150 researchers. The meetings original topic - funding priorities for the next year - was changed at the last minute SPECIFICALLY to talk about the Ross Ice Shelf because Ross had changed pace; "Data from the last 6 months indicated movement greater than the total recorded by our investigation in the preceding 6 years."

Our MC was masterful and solicited input from everyone, knowing who the key experts on various aspects of the issue were and asking for their input; someone cited the total known range of sea level change, another cited "where we are now".

At the end, our MC solicited opinions on the magnitude and pace of "significant world sea level rise", and my comments reflect the groups answers. Two, as I recall, thought significant change would take 100 years or more, five or so thought that less than 10 years was possible, but not likely. The vast majority were between 30 years and 60 years. "Collapse of Ross could take mere hours or a few days," the PI said, and no one could disprove him.

As for magnitude, _nobody_ was thinking less than 30 feet of increase, and nearly nobody was thinking more than 60 feet "soon", though all felt we were likely to see at least 100 feet increase "in the not too distant future."
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[NL207]

You are simply full of garbage.

The Ross Ice Shelf is just that, an ice shelf floating in water.

"Ice Shelves are permanent floating ice sheets " source: http://www.vims.edu/bio/microbial/NBPishelf.html

source: http://www.sciencedaily.com/releases/2002/03/020319075014.htm [Larsen shelf]

"Everything east of those mountains that appears to be land is actually the Ross Ice Shelf." source: http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=5256

source:http://en.wikipedia.org/wiki/Ross_Ice_Shelf

The Salient point is that the Ross Ice shelf is already floating in water. Now, some years back, a clever fellow named Archimedes observed that objects floating in water displace exactly thier own mass. When Ice melts, its volume is identical to the water it displaced. The total collapse of the Ross Ice Shelf, since it is composed entirely of ice, will not change the sea level 1 millimeter. Anyone who says differently than this is either claiming the Ross Ice Shelf is not a true ice shelf or is a liar.

[RTIII]

Hi Folks,

Yes, I'm your resident Earth Scientist. When I read the teaser, I though, OK, this is in my field, let's see what they're going to say... Frankly I was VERY surprised to see this posted. Alert HufPo readers will recall that on no less than three occasions, and perhaps more, I have written about the exact scenario posted here...

I hate to be the bearer of bad news but the story is way off the mark. Here are the problems with it.

First, they incorrectly make it sound as if there are two layers of ice. They would have you believe that there's some kind of ice sheet that's floating that inhibits glacier movement and prevent the land-based ice from moving into the ocean. This is absolutely false. The ice conjoins and should instead be thought of as a large area of ice wherein various regions may have different forces applied. The ice IS plastic - it deforms based upon various forces, but it's not like there's a solid board below over which icing flows. The visual they suggest is laughable.

Secondly, the timeline they suggest is laughable. Just a week ago we read here on HufPo about the more than an order of magnatude faster at which the arctic ice is melting than anticipated.

END PART I
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[Vyvjala]

And Bud is worried about selling seaworld........................