Sentences with phrase «much melting of ice sheets»

Some scientists and groups pushing for aggressive cuts in the gases said the panel was much too conservative in some projections, particularly in assessing how much melting of ice sheets might raise sea levels in the next 100 years.

Not exact matches

«The fact that a large portion of the western flank of the Greenland ice sheet has become dark means that the melt is up to five times as much as if it was a brilliant snow surface.»

Their results show that East Greenland has been actively scoured by glacial ice for much of the last 7.5 million years — and indicate that the ice sheet on this eastern flank of the island has not completely melted for long, if at all, in the past several million years.

Ullman said the level of CO2 that helped trigger the melting of the Laurentide ice sheet was near the top of pre-industrial measurements — though much less than it is today.

Better estimates of Pliocene sea levels will help geologists know how much of the ice sheets melted during that balmy era, Dowsett says, which may give us a glimpse of our own climate future.

Not only is Greenland's melting ice sheet adding huge amounts of water to the oceans, it could also be unleashing 400,000 metric tons of phosphorus every year — as much as the mighty Mississippi River releases into the Gulf of Mexico, according to a new study.

«Warming greater than 2 degrees Celsius above 19th - century levels is projected to be disruptive, reducing global agricultural productivity, causing widespread loss of biodiversity and — if sustained over centuries — melting much of the Greenland ice sheet with ensuing rise in sea levels of several meters,» the AGU declares in its first statement in four years on «Human Impacts on Climate.»

In the San Francisco Bay area, sea level rise alone could inundate an area of between 50 and 410 square kilometres by 2100, depending both on how much action is taken to limit further global warming and how fast the polar ice sheets melt.

When the planet's big ice sheets collapsed at the end of the last ice age, their melting caused global sea levels to rise as much as 100 meters in roughly 10,000 years, which is fast in geological time, Mann noted.

«Based on the UN climate panel's report on sea level rise, supplemented with an expert elicitation about the melting of the ice sheets, for example, how fast the ice on Greenland and Antarctica will melt while considering the regional changes in the gravitational field and land uplift, we have calculated how much the sea will rise in Northern Europe,» explains Aslak Grinsted.

Shepherd said, though, that there still is still a lot of uncertainty about how much additional melt in some locations of the Greenland ice sheet will actually be lost to the ocean.

A relatively small amount of melting over a few decades, the authors say, will inexorably lead to the destabilization of the entire ice sheet and the rise of global sea levels by as much as 3 meters.

On its own, sea level rise could inundate between 50 and 410 square kilometres of this area by 2100, depending on how much is done to limit further global warming and how fast the polar ice sheets melt.

The size of the ice sheet depends on how much new snow accumulates and how much of the existing ice melts, she said.

Since so much of the ice sheet is grounded underwater, rising sea levels may have the effect of lifting the sheets, allowing more - and increasingly warmer - water underneath it, leading to further bottom melting, more ice shelf disintegration, accelerated glacial flow, and further sea level rise, and so on and on, another vicious cycle.

Faced by the loss of so much precious coastal land, it seems quite plausible that our descendants will resort to some kind of mega-project to cool the planet and stop the ice sheets melting.

A new paper in Nature Climate Change by Bamber and Aspinall attempts to untangle the thorny problem of how quickly and how much the ice sheets of the world will melt.

However, it's quite a different matter melting a long - lived massive ice sheet up to 1.5 km thick that covers over 70 % of the land surface (as happened at the end of the last glacial period), from melting isolated and much thinner ice caps / sheets that only cover about 11 % of the land surface (i.e. present - day).»

The research published in Nature Communications found that in the past, when ocean temperatures around Antarctica became more layered - with a warm layer of water below a cold surface layer - ice sheets and glaciers melted much faster than when the cool and warm layers mixed more easily.

Either the glaciers would have to flow into the ocean at unrealistic rates, or rapid melting would have to be triggered over a much larger area of the ice sheet than current evidence suggests.

When projecting how sea levels could rise over the coming centuries, one of the most difficult factors for scientists to gauge is how much of the Earth's vast ice sheets will melt, and how quickly.

Scientific knowledge input into process based models has much improved, reducing uncertainty of known science for some components of sea - level rise (e.g. steric changes), but when considering other components (e.g. ice melt from ice sheets, terrestrial water contribution) science is still emerging, and uncertainties remain high.

Global ice - sheets are melting at an increased rate; Arctic sea - ice is disappearing much faster than recently projected, and future sea - level rise is now expected to be much higher than previously forecast, according to a new global scientific synthesis prepared by some of the world's top climate scientists.

Finally, if a zero melt day anomaly were to reflect ice - free conditions, as you suggest then, much of the southern and eastern portion of the ice sheet (blue - green areas in figure 1) would actually be exposed bedrock.

OCEANS RISING FAST, NEW STUDIES FIND Melting ice could raise levels up to 3 feet by 2100, scientists say David Perlman, Chronicle Science Editor Friday, March 24, 2006 Glaciers and ice sheets on opposite ends of the Earth are melting faster than previously thought and could cause sea levels around the world to rise as much as three feet by the end of this century and 13 to 20 feet in coming centuries, scientists are reportingMelting ice could raise levels up to 3 feet by 2100, scientists say David Perlman, Chronicle Science Editor Friday, March 24, 2006 Glaciers and ice sheets on opposite ends of the Earth are melting faster than previously thought and could cause sea levels around the world to rise as much as three feet by the end of this century and 13 to 20 feet in coming centuries, scientists are reportingmelting faster than previously thought and could cause sea levels around the world to rise as much as three feet by the end of this century and 13 to 20 feet in coming centuries, scientists are reporting today.

The IPCC Fourth Assessment Report did not specifically address these competing factors and essentially ignored the likelihood of much more rapid melting of Greenland and other land - based ice sheets.

If our ice sheets are going to change our sea level that much, from its current rate of melt, the melt rate would have to increase exponentially in the future.

In this regard, I would observe that at least one important AGW effect, rising sea level, does not depend on a specific regional outcome so much as on global mean T. (At least, I think this is so (because my understanding is that most of the rise comes from lower density of warmer water, not from melting ice sheets — though again, not 100 % sure on this point)-RRB-.

They have taken the acceleration in melting of the ice sheets to be a constant, and extrapolated into the future century, Hansen has proposed a much more threatening scenario where the rate of icesheet disintegration increases exponentially, doubling every decade.

However, because they are partly submerged, their direct contribution to sea level rise is much smaller than the contribution made by the melting of an equivalent volume of (land - based) ice sheets.

Perhaps you're equating the West Antarctic Ice Sheet (which IS melting and disintegrating) with the whole of Antarctica — a much larger area, much of which is not yet so affected by GW.

Re: T. Elifritz Due to the thermal inertia of the Greenaland and Antarctic ice sheets won't it be several millenia before they could completly melt away even under conditions much hotter than now?

Should the ice sheet start to melt in a serious way (i.e. much more significantly than current indications suggest), then lowering of the elevation of the ice sheet will induce more melting simply because of the effect of the lapse rate (air being warmer closer to sea level due to pressure effects).

Many important questions of environmental policy, however, involve inescapably uncertain outcomes... How much global warming will it take to trigger the irreversible collapse and melting of the Greenland ice sheet?»

The West Antarctic ice sheet would become unstable by the end of the century, although it might take another 10,000 years to melt the much larger East Antarctic sheet.

What scientists once thought was a fairly simple linear process — that is, a certain amount at the surface of an ice sheet melts each year, depending on the temperature — is now seen to be much more complicated.

First, modification of individual hurricanes would fall under the topic of weather modification, rather than climate geoengineering; and second, there is not nearly as much research on [hurricane modification] as on the possible effects of climate geoengineering on slowing the melting of ice sheets.

For example, conditions at the poles affect how much heat is retained by the earth because of the reflective properties of ice and snow, the world's ocean circulation depends on sinking in polar regions, and melting of the Antarctic and Greenland ice sheets could have drastic effects on sea level.

Melting continental ice sheets drove much higher rates of sea level rise than seen today, ranging from 10 to 40 + mm / year.

The melting of Greenland's ice sheet appears to be accelerating of late, losing about four times as much mass last year as it did a decade ago.

Over the long - term, melting of the West Antarctic Ice Sheet could yield as much as 10 to 14 feet of global average sea level rise, with local sea level rise varying considerably depending on land elevation trends, ocean currents and other factors.

Rather, the scientists don't know yet how much of Greenland and the West Antarctic ice sheets are going to melt or how fast it'll happen.

Global warming may not affect sea levels, study finds — January 11, 2008 Excerpt: Excerpt: The most pessimistic predictions of sea level rises as ice sheets are melted by global warming may have to be scaled back as a result of an extraordinary discovery that ice persisted when the Earth was much hotter than today.

Examples; CO2 levels in the atmosphere correlate directly with human population (lots of breathing) and thus population control can avoid climate change (hard to disprove) Melting of the Artic ice sheet is good as shipping route will become shorter and transportation costs much less.

And this way, they also got the longest possible record, striking bedrock after seeing ice that was 250,000 years old, the date of the warm period before last, the one that melted much of Greenland's ice sheet.

If all of Totten were to melt, it would be enough to raise seas by around 11 to 13 feet — or about as much as if half of the entire Greenland Ice Sheet went down.

According to the study, this is because of the expansion of warming waters, which caused as much sea level rise from 2002 through 2014 as the melting of all the glaciers and the Greenland and Antarctic ice sheets combined.

Either the glaciers would have to flow into the ocean at unrealistic rates, or rapid melting would have to be triggered over a much larger area of the ice sheet than current evidence suggests.

They based their findings on analysis of the chemical isotopes locked in ancient ice from the Weddell Sea embayment, and the evidence suggests that in the past, when polar waters became more stratified, the ice sheets melted much more quickly.

RE: 4th Error -RCB- Poses an objection to the non-scientific term catastrophic [NOTE: Scientific «consensus» is often being used & / or implied in standard climate - change discourse - Yet Consensus is a Political Term - NOT a Scientific Term]- HOWEVER - When Jim Hansen, the IPCC & Al Gore, et - al - go from predicting 450 — 500 ppm CO2 to 800 — 1000ppm by the end of the 21st century -LCB- said to the be highest atmospheric CO2 content in 20 — 30 Million YRS -RCB-; — & estimates for aver global temps by 21st century's end go from 2 * C to 6 * C to 10 * C; — & increased sea level estimates go from 10 - 20 cm to 50 - 60 cm to 1M — 2M -LCB- which would totally submerge the Maldives & partially so Bangladesh -RCB-; — predictions of the total melting of the Himalayan Ice caps by 2050, near total melting of Greenland's ice sheet & partial melting of Antarctica's ice sheet before the 21st century's end; — massive crop failures; — more intense & frequent hurricane -LCB- ala Katrina -RCB- for much longer seasonal durations, etc, etc, etc... — IMO That's Sounds pretty damned CATASTROPHIC to Ice caps by 2050, near total melting of Greenland's ice sheet & partial melting of Antarctica's ice sheet before the 21st century's end; — massive crop failures; — more intense & frequent hurricane -LCB- ala Katrina -RCB- for much longer seasonal durations, etc, etc, etc... — IMO That's Sounds pretty damned CATASTROPHIC to ice sheet & partial melting of Antarctica's ice sheet before the 21st century's end; — massive crop failures; — more intense & frequent hurricane -LCB- ala Katrina -RCB- for much longer seasonal durations, etc, etc, etc... — IMO That's Sounds pretty damned CATASTROPHIC to ice sheet before the 21st century's end; — massive crop failures; — more intense & frequent hurricane -LCB- ala Katrina -RCB- for much longer seasonal durations, etc, etc, etc... — IMO That's Sounds pretty damned CATASTROPHIC to ME!