Where can I find a post-global-warming map of the earth?

October 13, 2005 6:43 PM

Where can I find a non-batshitinsane version of this map?

Assume: Earth's ice caps melt.

How much would the sea level rise?* As a result of the increased level, what would a map of the world (or specific areas) look like? Has anyone done a serious study of this from a physics perspective? I'm not interested in purchasing one or anything, just interested in seeing more than thumbnails and "artists' renditions."

*I'm just assuming it would rise - wouldn't it?

posted by odinsdream to science & nature (17 comments total)

Can't help you with the map, but I can point out that the primary reason for rising sea levels due to global warming is not so much the melting of the ice caps, but simply thermal expansion of seawater.
posted by Brian James at 6:59 PM on October 13, 2005

What is up with that map? He appears to show a large chunk of the American west covered in water, but most of that area is now at over 4000 feet above sea level.
posted by neuron at 7:13 PM on October 13, 2005

I remembered seeing a National Geographic story about this, and some googleing found it here.

Along the way I also found this, and then a better version of it from here.
posted by gus at 7:20 PM on October 13, 2005

I'm curious about this as well. I have often pondered just how much !@#$ water it would take to cover the entire global ocean surface with a single foot extra. I cannot imagine risings of more than 5 or 10. But then I don't have a clue what I'm talking about.
posted by scarabic at 7:20 PM on October 13, 2005

Yeah, no shit neuron, 1st thing I noticed after the Mississippi river. Perhaps odinsdream'sais for the "non-batshitinsane" version?

I've always loosely heard a rise of up to a couple meters, enough to impact 3/4 of the world's population which supposedly lives within 50-100 miles of the shore. Google???
posted by Pressed Rat at 7:21 PM on October 13, 2005

Oot! that should be odinsdreams basis
posted by Pressed Rat at 7:21 PM on October 13, 2005

Ooh, better yet! Here is a an applet that lets you build your own rising sea level maps!
posted by gus at 7:25 PM on October 13, 2005

Perhaps odinsdream's basis for the "non-batshitinsane" version?

Bingo. The map I linked to is cleary messed up in several ways, like the fact that it's the result of one man's "visions." It was just meant as a starting point to give people an idea of what I was looking for.

gus, thanks for the link - it doesn't appear to work with Safari though. The processing bar fills up, then the map vanishes before updating. I'll try it tomorrow at work with IE and might have better luck.
posted by odinsdream at 7:35 PM on October 13, 2005

I kind of doubt that a global scale map will look impressive, unless it's done by an absurdist.

It would likely look a lot worse once you start examining where population centers are, and how they'd be affected by a few feet of water.
posted by I Love Tacos at 7:58 PM on October 13, 2005

I Love Tacos, I'd like to see detailed area maps, too.
posted by odinsdream at 8:13 PM on October 13, 2005

Can't help you with the map, but I can point out that the primary reason for rising sea levels due to global warming is not so much the melting of the ice caps, but simply thermal expansion of seawater.

The what?

(the volume of water will change less then 0.1% with a temprature change of 10 degrees or so)
posted by delmoi at 8:38 PM on October 13, 2005

Can't help you with the map, but I can point out that the primary reason for rising sea levels due to global warming is not so much the melting of the ice caps, but simply thermal expansion of seawater.
posted by Brian James at 6:59 PM PST on October 13 [!]

Yeah, except you just made that shit up.
posted by angry modem at 9:18 PM on October 13, 2005

Uh, no.

From the Columbia University Metropolitan East Coast Assessment (basically a group concerned with how global warming will affect cities:

Sea level has been rising, on average, between 1 to 2.5 mm/yr for the last 100-150 years, with 1.8 mm/yr a "best estimate". This historic rise in sea level is most probably linked to the observed global increase in temperature over the same period. IPCC The recent sea-level rise comes from the thermal expansion of the upper ocean layers and melting of mountain glaciers. The contributions from the Greenland and Antarctic ice sheets are not as well-established and may be close to zero at present.

From Science, March 18 2005,

If the emission of greenhouse gases were to stop today, their associated global warming would continue because of the long lifetime of the gases in the atmosphere and thermal inertia of the ocean, and sea level rise would continue because of thermal expansion. Two modeling studies address these issues. Both studies conclude that even in these best-case scenarios, temperatures will rise by as much as 0.5 degrees C and sea level will rise by tens of centimeters, not including any melting from ice sheets and glaciers.

From the Union of Concerned Scientists:

By 2100, sea level is estimated to rise by an additional 46 to 58 cm, with an estimated total range of 20 to 86 cm (Warrick et al., 1996). Over half of the change will likely be from thermal expansion of ocean water, another 30% from melting of mountain glaciers, and 10% from melting of parts of the Greenland ice sheet (Gregory and Oerlemans, 1998).

It is true, however, that the original poster's hypo regarding the ice caps melting completely would probably be more significant than the thermal expansion effect, but in the present and near-future it is a more substantial cause.
posted by Brian James at 10:07 PM on October 13, 2005

BY comparison, at the end of the last ice age, global sea levels rose around 120 metres, not accounting for localized depression and rebound of the land mass due to weight of ice. In some areas this rise averaged about 5 cm per year, but in most areas it was much less. This rise is almost entirely due to the melting of the ice sheets and subsequent re-entry of melt water into the oceans.

If all the current ice caps and glaciers on earth melted (including all of Antarctic and Greenlandic sheets), global sea level would rise about 70 metres.

Each year around 1 cm of the collective surface of Earth's water bodies falls as winter snow on the current ice caps. This needs to be balanced by a collective 1 cm of summer runoff for sea level to stay stable. Clearly, it takes very drastic climatic changes to make a rapid change in sea level -- if there was no runoff then sea level would only fall by 1 cm/year, all else being equal. (And by rapid, I mean rapid at a human, not a geological scale)

The average depth of the ocean is about 4000 metres. A 0.1% thermal expansion of that entire water mass (currently it is just the surficial water but eventually that would balance across the ocean system) should produce only a 4 metre rise globally. I am no oceanographer, but the deep ocean conveyers operate at century or millennial scales of mixing so I would be surprised to see that amount of thermal expansion at short time intervals. Further I have no data on thermal expansion of water by temperature, though that should be easily searchable.

Regarding non-batshit insane maps, you can pretty much do this with contours yourself. Assume a worst case 70 metre rise n ocean level then look for that 70 metre (225 foot) contour and thats your new coastline ..... the flatter the area, the more it will be flooded in the horizontal sense
posted by Rumple at 11:08 PM on October 13, 2005

What the hell is the huge continent that suddenly appears between New Zealand and South America in the matrix institute world map supposed to be? Ry'leh??
posted by bifter at 2:00 AM on October 14, 2005

gus's links are fascinating for how little difference it would make. Almost everything still has the same outlines, although I'm sure a bunch of coastline is carved off. Except for Florida and Louisiana, which are just gone.
posted by smackfu at 7:03 AM on October 14, 2005

"Where can I find a post-gloabl-warming map of the earth?"

How about on your coffee mug?

bifter, I'm guessing that's supposed to be a new above-sea-level land mass formed by volcanic activity, perhaps triggered by the warming.
posted by attercoppe at 6:22 PM on October 14, 2005