Global warming raise sea levels?

[TheUnknown]

I know this may sound extremely silly... but, all ice at the north pole is floating... creating mass that would make the ocean higher than it would be... would that ice not be there, when ice melts it takes up less volume than when it is frozen? How would the north and south poles melting raise sea levels "dramatically" , yes i know this will sound silly to a lot of you, but I'm serious! can anyone give me a solid answer? I can see how it would effect our weather, causing different currents in the ocreans, but coastal flooding, really a huge deal? maybe only on a small scale? and wouldn't a small percentage of that melted water be evaporated into the atmosphere(which would keep sea levels down slightly), and become clouds? creating more chaotic weather, and different weather patterns? and fill up old dry lake beds and seas that have since dried uop with new water, displacing water fairly equally throughout the globe?

 

[matthyaouw]

I think get where you are coming from. I believe its true that floating ice takes up no more volume than the water would, due to the portion above the surface, so melting of floating ice won't cause sea level rise. The ice sheets that pose problems are the Greenland and Antarctic, as these are almost entirely on land and displace no sea water as they are.

 

[TheUnknown]

Thanks, i see this on the news everyday being discussed by top scientists etc... and it erks me, because i am a 20 year old 5 year high school student... it seems they miss things? Yes i know polution is a problem, but if that's what they are trying to get at, then adress it honestly so people take you seriously? Thanks for understanding, yes i agree the ice sheets are the big problem, but are they really enough to cause GLOBAL coastal flooding, after displacing water in deserts because of new weather patterns? Like i always tell people, we should fear the next ice age more than global warming :) Don't get me wrong, i am not in any way saying we should ignore it, because it is still part of the unknown.

 

[matthyaouw]

Its a bit speculative to say that melting ice would be counterbalanced by increased precipitation in deserts, because the amount of water stored at the poles is tremendous, and if anything, I think deserts are expanding and droughts becoming more frequent, plus any water that lands on a continent will make it back to the sea in a relatively short time.
There are a lot of good threads around this section on global warming, I reccomend you check them out.

 

[juju]

Hi,

I have read that if all the ice in the world melted, sea levels could rise hundreds of feet. This in and of itself wouldn't increase precipitation.

However, increased evaporation due to global warming would. This could magnify the GW effect since water vapor is itself a greenhouse gas. This would mean more precipitation and more global warming.

The result could mean a hotter more humid earth. And, since temperature (especially ocean temperature) is a major driver of storm intensities, this could reult in more dangerous and devasting storms.

juju

 

[Andre]

Well there you go. We need to be scaremongered I guess. I have a story about devils and dragons too.

https://www.physicsforums.com/showthread.php?t=54723

 

[TheUnknown]

Well there you go. We need to be scaremongered I guess. I have a story about devils and dragons too.

https://www.physicsforums.com/showthread.php?t=54723

haha yes, it seems our thought processes revolve on a quite even playing field... i read that whole topic, and it is exactly the way i feel.. although i never talk about it, because isntantly i am laughed at and become "the enemy". It doesn't take much thought and common sense to see what the real threats are and aren't. Polution is a real threat, i guess the only way they try and get it across to the masses is to say that they're homes will be flooded under 300 feet of ocean if they continue to drive cars.

 

[TRCSF]

it seems they miss things?

It seems a lot of people who go on about melting ice cube not raising the level of water in a glass point are missing something.

That is, there's a whole lot of ice sitting on Greenland and Antartica, and it'll be melting too.

Plus there's a whole lot of important species and peoples that depend on the polar ice caps now.

 

[Allegro]

In Chapter 11 of the IPCC ''Climate Change 2001'' Report an overview is given and the physical causes of the factors contributing to sea-level change are evaluated:
http://www.grida.no/climate/ipcc_tar/wg1/408.htm

The impact of the change of the sealevel on the population in coastal zones is evaluated here:
http://www.grida.no/climate/ipcc_tar/wg2/index.htm

 

[TheUnknown]

It seems a lot of people who go on about melting ice cube not raising the level of water in a glass point are missing something.

That is, there's a whole lot of ice sitting on Greenland and Antartica, and it'll be melting too.

Plus there's a whole lot of important species and peoples that depend on the polar ice caps now.

i agree, it's a misfortune, and the Earth was not intended to be treated this way, that is and should be the real message. I agree the ice sheets melting on land may or may not have some effect, we just do not know, there are so many tings you could say to scare people, but on the other hand there are so many things yoiu could say that would counter it, so who's to believe? I can write a book saying how the warm environment will bring deserts to life, and fill dried seas and lakes, and that the highest mountains will gather more ice from global warming, isn't that all this is about, it hasn't happened, no one knows what will happen, so instead of going by the real facts, that pollution is bad and the Earth was not meant for it, we make predictions that may ofr may not be false, so we can scare people into stopping what they are doing... maybe that's the best way to go about, but i prefer truth over speculation, i could also sit here and give you lots of stats and surveys and records, but it doesn't mean a thing... they said global warming would cause the globe to warm by 5 degrees on average... is it really that big of a deal? Why don't we start talking about what it's going to do to the future evolution of humans, the chemicals causing deformities in both humans and animals. i say we stick to the truth, the Earth was not meant to have so much exhaust and chemicals flying around in its atmosphere, so we should stop using them... the ice sheets flooding is always a possibility... but we only pick it because it's the worst case scenario, and it will scare the heck out of people... and of course everyone jumps on the band wagon.

 

[paul-martin]

Another factor to mention is that the ice reflect the sun beam, and we get much less infrared radiation from those areas. But i don't know how much this reduce the global warming.

 

[Andre]

there's a whole lot of ice sitting on Greenland and Antartica, and it'll be melting too.

It's time that scaremongering should be considered a mis conduction. Unfortunately, it's a requirement of the society

Science, Vol 295, Issue 5554, 476-480 , 18 January 2002


Positive Mass Balance of the Ross Ice Streams, West Antarctica
Ian Joughin,1* Slawek Tulaczyk2*

We have used ice-flow velocity measurements from synthetic aperture radar to reassess the mass balance of the Ross Ice Streams, West Antarctica. We find strong evidence for ice-sheet growth (+26.8 gigatons per year), in contrast to earlier estimates indicating a mass deficit (20.9 gigatons per year). Average thickening is equal to ~25% of the accumulation rate, with most of this growth occurring on Ice Stream C. Whillans Ice Stream, which was thought to have a significantly negative mass balance, is close to balance, reflecting its continuing slowdown. The overall positive mass balance may signal an end to the Holocene retreat of these ice streams.

A cutting edge reseacher: http://www.toddAlbert.com/research.htm

Believe it or not, we still do not know for certain whether the Greenland Ice Sheet is growing or shrinking.

 

[TheUnknown]

scientists... be wary... global warming and freezing occurs when IT wants to, us humans are merely a bi-product of this great universe. stop pollution... adapt to your changing earth.

 

[Phobos]

I agree the ice sheets melting on land may or may not have some effect, we just do not know...

It's clear that the sea levels have changed quite a bit throughout the Earth's history (e.g., consider the oft-cited example of the Bering Strait). And although I don't have the data handy, I assume sea levels corrolate very well with the amount of polar ice (the water must go somewhere).

so instead of going by the real facts, that pollution is bad and the Earth was not meant for it,

Not sure we can call those facts. "Pollution" is subjective (e.g., one creature's waste is another's food) and we know of no higher purpose for the Earth other than through religious faiths. The real question is what kind of future do we want (i.e., what kind of future is healthy for us and how do we achieve that)?

we make predictions that may ofr may not be false, so we can scare people into stopping what they are doing...

We make the best predictions we can and make decisions based on that (and then collect more data & make revised predictions to make revised decisions...etc.). Certainly scaremongering is out there as well as ignoring warning signs, but there can be a healthy scientific/political debate on it.

they said global warming would cause the globe to warm by 5 degrees on average... is it really that big of a deal?

Yes. The difference between an ice age and current conditions is only about 5 to 8 degrees C (it's a global average).

 

[Phobos]

global warming and freezing occurs when IT wants to

Well, that's a big part of the debate...to what degree are humans affecting the climate/planet. I'd say it's non-zero, but I couldn't tell you to what degree it is. Much of the "scaremongering" can come from the uncertainties in what will happen from our actions.

 

[Andre]

And although I don't have the data handy, I assume sea levels corrolate very well with the amount of polar ice (the water must go somewhere).

Not really

http://www.cuba.cu/ciencia/citma/ama/museo/exmari.htm

http://geology.geoscienceworld.org/cgi/content/full/30/4/379

they said global warming would cause the globe to warm by 5 degrees on average... is it really that big of a deal?

Yes. The difference between an ice age and current conditions is only about 5 to 8 degrees C (it's a global average).

Indeed the assumed mechanism of the ice age of ~10 difference is based on three indicators, the borehole temperature in the remaining holes of the Greenland ice sheet and only there) and the changing isotope ratios in the ice cores as well as oceanic sediment cores. And the signs of waxing and waning ice sheets.

Detailed investigation reveals that's nothing is what it looks like.

 

[Andre]

That second link seems dead. Here is the abstract of that paper:

Beijing inundated by the sea within the past 80 k.y.: Nannofossil evidence
Wuchang Wei*
Scripps Institution of Oceanography, University of California, San Diego, California 92093, USA

ABSTRACT
Examination of published data reveals that a marine bed in Beijing can be dated as 80 ka or younger on the basis of abundant nannofossils. This age is 30 times younger than that published previously on the basis of magnetostratigraphic and biostratigraphic interpretations. The abundant nannofossils and foraminifers suggest that Beijing was inundated by the sea within the past 80 k.y. The very recent nature of this marine transgression has profound societal and geological implications and thus calls for new studies and thorough evaluation of all relevant data sets.

So what do you think, should we do new studies?

 

[Phobos]

I meant on a global scale/global average (local variations are to be expected).

 

[Andre]

Yes of course and there is no doubt that the late Pleistocene ice sheets Cordilleran, Innutian, and Laurentian from America and the Weichselian and Würm glaciations have dissappeared and have caused a world wide (eustatic) sea level rise. However the only places where nice correlating paleao sea levels are found is in the East Carribean and around Indonesia. . The corals of Barbados are famous for that. Also the North sea and the Beringia land bridge dissappeared. On other places however, like October revolution Island north of Siberia, young -not petrified- fossil remains of Beluga whales are found 100 meters above sea level.

So it's seems not to be the whole story.

 

[Andre]

Take this for instance:

Yamaguchi M Ota, Y (2004) Tectonic interpretations of Holocene marine terraces, east coast of Coastal Range, Taiwan Quaternary International Volumes 115-116 , 2004, Pages 71-81

Abstract
The east coast of the Coastal Range in Taiwan is well known for its multiple Holocene marine terraces and their very rapid uplift. The study area extends from Hualien to Taitung over ca 150 km of coastline. Here, we present some new data on the age and height of Holocene marine terraces, and we discuss their significance for Holocene coastal tectonics.

The Holocene marine terrace sequence is subdivided into a maximum of 10 steps. The highest and oldest terrace, mostly underlain by transgressive deposits, represents the sea-level position of the culmination of Holocene sea-level rise and reaches up to ca 80 m above sea level. Transgressive deposits are radiocarbon dated at several sites, back to ca 13,000 yr BP. The lower terraces are mostly erosional ones, overlain by thin coral beds in situ, less than 1 m thick, and indicate successive lowering of relative sea level during the late Holocene. The uplift rate of the coast is very high, ranging from 5 to 15 m/ka.

And no ice sheet around in millions of years. So isostatic rebound after glaciation is not a factor.