Sentences with phrase «for ice sheet mass»

«The most reliable indication of the imminence of multi-meter sea level rise may be provided by empirical evaluation of the doubling time for ice sheet mass loss.»

Not exact matches

Subtracting one from the other produced a «mass - balance» picture of net ice loss or growth for each ice sheet.

GNET, short for «Greenland GPS Network,» uses Earth's natural elasticity to measure the mass of the ice sheet.

Although that is unlikely to happen for many thousands of years, the ice sheet has increasingly lost mass over the last two decades, and the glaciers that serve as its outlet to the sea are accelerating.

Despite being trumpeted in certain circles as meaning that there's really nothing to worry about regarding the Greenland ice sheet, the authors made a point of noting (although not in this press release) that an additional source of mass loss needs to be identified in order to reconcile their results with the GRACE data (which do not show a reduction in mass loss for the same period).

His comments are based on the paper «Limits in detecting acceleration of ice sheet mass loss due to climate variability», B. Wouters, J. L. Bamber, M. R. van den Broeke, J. T. M. Lenaerts and I. Sasgen, Nature Geoscience 6, 613 — 616 (2013) doi: 10.1038 / ngeo1874 Find the abstract and illustrations for that paper here.

This implies that large - scale observations — for example, of global mean sea - level change or of the change mass of the Antarctic ice sheet — will not on their own significantly narrow the range of late - century sea - level projections for decades to come.

This spring, NASA and the German Research Centre for Geosciences are scheduled to launch the Gravity Recovery and Climate Experiment Follow - On (GRACE - FO) mission, twin satellites that will continue the original GRACE mission's legacy of tracking fluctuations in Earth's gravity field in order to detect changes in mass, including the mass of ice sheets and aquifers.

Ice shelves are important, because they play a role in the stability of the Antarctic Ice Sheet and the ice sheet's mass balance, and are important for ocean stratification and bottom water formation; this helps drive the world's thermohaline circulatiIce shelves are important, because they play a role in the stability of the Antarctic Ice Sheet and the ice sheet's mass balance, and are important for ocean stratification and bottom water formation; this helps drive the world's thermohaline circulatiIce Sheet and the ice sheet's mass balance, and are important for ocean stratification and bottom water formation; this helps drive the world's thermohaline circulaSheet and the ice sheet's mass balance, and are important for ocean stratification and bottom water formation; this helps drive the world's thermohaline circulatiice sheet's mass balance, and are important for ocean stratification and bottom water formation; this helps drive the world's thermohaline circulasheet's mass balance, and are important for ocean stratification and bottom water formation; this helps drive the world's thermohaline circulation.

If ice sheet disintegration reaches a point such that the dynamics and momentum of the process take over, at that point reducing greenhouse gases may be unable to prevent major ice sheet mass loss, sea level rise of many meters, and worldwide loss of coastal cities — a consequence that is irreversible for practical purposes.

I would also cite Zwally et al (2005) for evidence from the Greenland Ice Sheet and the East Antarctic Ice Sheet mass balances that are consistent with increasing winter precipitation and warmer temperatures.

In the couple of decades leading up to the most recent IPCC report, the ice sheets were losing slightly less than 0.001 % of their mass per year, a rate that would require more than 100,000 years to remove all of the ice, and the equivalent of me going on a diet for a year and losing about 1/3 of one potato chip.

If a negative surface mass balance were sustained for millennia, that would lead to virtually complete elimination of the Greenland ice sheet and a resulting contribution to sea level rise of about 7 m.

I do think it has been clear for a while that interactions with the ocean provide the greatest potential for surprises and rapid changes, and that Greenland's ice sheet would mostly pull out of the ocean before it lost most of its mass.

• Current global model studies project that the Antarctic ice sheet will remain too cold for widespread surface melting and is expected to gain in mass due to increased snowfall.

But again the «models» estimate includes an observed ice sheet mass loss term of 0.41 mm / year whereas ice sheet models give a mass gain of 0.1 mm / year for this period; considering this, observed rise is again 50 % faster than the best model estimate for this period.

In light of this prediction and global climate model forecasts for continued high - latitude warming, the ice sheet mass budget deficit is likely to continue to grow in the coming decades.

Figure 3: Estimated ice mass change over time for the entire Antarctic ice sheet, West Antarctica, West Antarctica without the rapidly changing Amundsen Sea Coast (ASC) region and East Antarctica.

If all of the currently attainable carbon resources [estimated to be between 8500 and 13.600 GtC (4)-RSB- were burned, the Antarctic Ice Sheet would lose most of its mass, raising global sea level by more than 50 m. For the 125 GtC as well as the 500, 800, 2500, and 5000 GtC scenarios, the ice - covered area is depicted in white (ice - free bedrock in browIce Sheet would lose most of its mass, raising global sea level by more than 50 m. For the 125 GtC as well as the 500, 800, 2500, and 5000 GtC scenarios, the ice - covered area is depicted in white (ice - free bedrock in browice - covered area is depicted in white (ice - free bedrock in browice - free bedrock in brown).

Postscript: A grouping of 40 + scientists, including four of our Nature co-authors, participated in the NASA / ESA Ice Sheet Mass Balance Intercomparison project (IMBIE) in an attempt to understand the reasons for previously disparate ice mass change estimatIce Sheet Mass Balance Intercomparison project (IMBIE) in an attempt to understand the reasons for previously disparate ice mass change estimatice mass change estimates.

Because ice sheets contain so much ice and have the potential to raise or lower global sea level so dramatically, measuring the mass balance of the ice sheets and tracking any mass balance changes and their causes is very important for forecasting sea level rise.

Then in 2003 the launch of two new satellites, ICESat and GRACE, led to vast improvements in one of the methods for mass balance determination, volume change, and introduced the ability to conduct gravimetric measurements of ice sheet mass over time.

Figure 2: Ice mass changes for the Antarctic ice sheet from April 2002 to February 20Ice mass changes for the Antarctic ice sheet from April 2002 to February 20ice sheet from April 2002 to February 2009.

Figure 2: Time series of ice mass changes for the Greenland ice sheet estimated from GRACE monthly mass solutions for the period from April 2002 to February 2009.

NYC may not drown but depending on which ice sheet loses the most mass (for gravitational reasons) there are reasons to be worried about how much water could raise in the regions.

Given enough time, a negative net mass balance will ultimately lead to complete melting of the ice sheet, and several studies have attempted to quantify the climatic threshold and time period required for this to happen.

Second, he demonstrated that prevailing estimates of the 20th century GMSL rise (~ 1.5 to 2.0 mm / year), after correction for the maximum signal from ocean thermal expansion, implied mass flux from ice sheets and glaciers at a level that would grossly misfit the residual GIA - corrected observations of Earth's rotation.

A wealth of historical imagery exists for Greenland, and scientists could use this data to develop even more detailed histories of the ice sheet, and to determine whether the Greenland Ice Sheet was at equilibrium — not losing or gaining mass — in recent timice sheet, and to determine whether the Greenland Ice Sheet was at equilibrium — not losing or gaining mass — in recent tsheet, and to determine whether the Greenland Ice Sheet was at equilibrium — not losing or gaining mass — in recent timIce Sheet was at equilibrium — not losing or gaining mass — in recent tSheet was at equilibrium — not losing or gaining mass — in recent times.

DMI says, The surface mass balance is calculated over a year from September 1st to August 31st (the end of the melt season) For the 2016 - 17 SMB year, which ended yesterday, the ice sheet had gained 544bn tonnes of ice, compared to an average for 1981 - 2010 of 368bn tonnFor the 2016 - 17 SMB year, which ended yesterday, the ice sheet had gained 544bn tonnes of ice, compared to an average for 1981 - 2010 of 368bn tonnfor 1981 - 2010 of 368bn tonnes.

The Greenland ice sheet is poised for another record melt this year, and is approaching a «tipping point» into a new and more dangerous melt regime in which the summer melt area covers the entire land mass, according to new findings from polar researchers.

«It is very likely that the rate of global mean sea level rise during the 21st century will exceed the rate observed during 1971 — 2010 for all Representative Concentration Pathway (RCP) scenarios due to increases in ocean warming and loss of mass from glaciers and ice sheets.

The only comprehensive study of the Antarctic Ice Sheet mass was a 10 + year study based on continuous 24/365 satellite measurements over the period 1993 to 2003, covering 80 % of the AIS with estimates from other methods for the remaining 20 %, which can not be measured by satellites (coastal areas and polar regions).

«Models traditionally have projected that this difference doesn't become negative (i.e. net loss of Antarctic ice sheet mass) for several decades,» Mann said, adding that detailed gravimetric measurements, which looks at changes in Earth's gravity over spots to estimate, among other things, ice mass.

The most - optimal values for changes in bedrock elevation (GIA) in response to ice sheet mass changes have to be used

For Antarctica as a whole, the study found the current rate of ice sheet mass loss to be about 160 billion metric tons of ice per year.

Although the satellites are considered the gold - standard for measuring and observing sea levels, hurricanes / typhoons, ozone holes, sea ice, atmospheric CO2 distribution, polar ice sheet masses and etc., the same 24/7 technology used to measure temperatures across the entire habitable world is now being ignored (i.e., denied) due to the above inconvenient evidence.

When these factors are equal, the mass budget is balanced, but for years the Greenland Ice Sheet has had a negative mass budget, meaning the ice sheet is losing mass overaIce Sheet has had a negative mass budget, meaning the ice sheet is losing mass oveSheet has had a negative mass budget, meaning the ice sheet is losing mass overaice sheet is losing mass ovesheet is losing mass overall.

The values for the Antarctic ice sheet mass balance from NASA GRACE are the most current available (to January 2017).

This is in this: The Cryosphere Estimation of the Greenland ice sheet surface mass balance for the 20th and 21st centuries X. Fettweis1, E. Hanna2, H. Gall» ee3, P. Huybrechts4, and M. Erpicum1

For additional perspective, consider that the West Antarctic Ice Sheet which has long experienced modest warming contains less than 10 % of the continent's ice maIce Sheet which has long experienced modest warming contains less than 10 % of the continent's ice maice mass.

Recent observations of unpredicted, local acceleration and consequent loss of mass from both ice sheets (Alley et al., 2005) underscores the inadequacy of existing ice - sheet models, leaving no generally agreed basis for projection, particularly for WAIS (Lemke et al., 2007 Section 4.6.3.3; Meehl et al., 2007 Sections 10.6.4.2 and 10.7.4.4; Vieli and Payne, 2005).

And in Greenland, the ice sheet continued to lose mass this year, as it has for every year since satellite - based measurements began there in 2002, according to the report.

For example, if ice sheet mass loss becomes rapid, it is conceivable that the cold fresh water added to the ocean could cause regional surface cooling [199], perhaps even at a point when sea level rise has only reached a level of the order of a meter [200].

If ice sheet disintegration reaches a point such that the dynamics and momentum of the process take over, at that point reducing greenhouse gases may be unable to prevent major ice sheet mass loss, sea level rise of many meters, and worldwide loss of coastal cities — a consequence that is irreversible for practical purposes.

Our atmosphere - ocean model shows that the freshwater spurs amplifying feedbacks that would accelerate ice shelf and ice sheet mass loss, thus providing support for our assumption of a nonlinear ice sheet response.

Data for the modern rate of annual ice sheet mass changes indicate an accelerating rate of mass loss consistent with a mass loss doubling time of a decade or less (Fig. 10).

Going forwards, IMBIE provides a framework for assessing ice sheet mass balance, and has an explicit aim to widen participation to enable the entire scientific community to become involved.

[3] Greenland's ice sheet is losing mass at about 300 cubic kilometres per year, with potentially devastating consequences for sea level rises.

And more recent estimates of the Antarctic mass balance contribution to sea level rise has the East Antarctica ice sheet gaining mass at a more accelerated pace for 2003 - 2013 than the mere +14 Gt per year identified by Shepherd et al. (2012) for 1992 - 2011.

For example, Martín - Español et al. (2017) find that the total mass trend for the East Antarctic Ice Sheet was a gain of +57 Gt per year during 2003 - 2013, which is 4 times the rate of gain assessed for 1992 - 20For example, Martín - Español et al. (2017) find that the total mass trend for the East Antarctic Ice Sheet was a gain of +57 Gt per year during 2003 - 2013, which is 4 times the rate of gain assessed for 1992 - 20for the East Antarctic Ice Sheet was a gain of +57 Gt per year during 2003 - 2013, which is 4 times the rate of gain assessed for 1992 - 20for 1992 - 2011.