Sentences with phrase «cordilleran ice sheet mass»

Cordilleran Ice Sheet mass loss responded to climate reversals near the Pleistocene Termination

The reconstructed curve includes isolated rapid events of several decimetres within a few centuries, one of which is most likely related to loss from the Antarctic ice sheet mass around 5000 years before present.

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.

The ICESat mission provided multi-year elevation data needed to determine ice sheet mass balance as well as cloud property information.

That estimate was based in part on the fact that sea level is now rising 3.2 mm / yr (3.2 m / millennium)[57], an order of magnitude faster than the rate during the prior several thousand years, with rapid change of ice sheet mass balance over the past few decades [23] and Greenland and Antarctica now losing mass at accelerating rates [23]--[24].

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.

Equation S1 implies that when SMB - D is negative but constant in time, ice sheet mass will decrease linearly in time.

A pedantic treatment would use a logistics function since we know there is only so much ice sheet mass to be lost.

Has realclimate ever done (or considered doing) an entry about the immense contribution that satellite measurements have made in the past two - three decades, in helping us to understand various components of the earth system (e.g., vegetation, ozone, ice sheet mass, water vapor content, temperature, sea level height, storms, aerosols, etc.)?

How certain is it that ice sheet mass balances were in equilibrium during that time?

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.

Without the moderating effects of increased snowfall and refreezing, post-1996 Greenland ice sheet mass losses would have been 100 % higher.

Accelerated ice discharge in the west and particularly in the east doubled the ice sheet mass deficit in the last decade from 90 to 220 cubic kilometers per year.

This is despite using observed ice sheet mass loss (0.19 mm / year) in the «modelled» number in this comparison, otherwise the discrepancy would be even larger — the ice sheet models predict that the ice sheets gain mass due to global warming.

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.

The software developed will combine individual assessments of ice sheet mass balance to determine a reconciled estimate of ice sheet mass balance, taking into account the spatial and temporal domain of the input data and their uncertainties, and generate summary graphical and tabulated output.

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.

A key area of glaciological study in recent years is ice sheet mass balance.

Ice sheet mass decreased at 152 ± 80 cubic kilometers of ice per year, equal to 0.4 ± 0.2 millimeters of sea level rise per year.

Surface melt on an ice sheet not only directly reduces the ice sheet mass but also can accelerate ice flow and even leads to further melting.

The impacts of ice shelf collapse and ensuing glacier acceleration are substantial, but in general, the effects of ocean melt are proving to be far more important in controlling ice sheet mass balance.

CryoSat - 2 observations taken between November 2010 and September 2013 indicate annual ice sheet mass losses of 134 ± 27 gigatons in West Antarctica, 3 ± 36 gigatons in East Antarctica, and 23 ± 18 gigatons on the Antarctic Peninsula.

Because Antarctica drains more than 80 percent of its ice sheet through floating ice shelves, accelerated glacier flow has the potential to affect ice sheet mass balance dramatically and raise sea level (Pritchard et al. 2012).

(Ice sheet mass balance (MB) is the difference between surface mass balance (SMB) and solid ice discharge across the grounding line (D).)

So the 2016 - 2017 Surface Mass Balance of approximately 550 Gt yr ^ -1 may seem to have caused a positive ice sheet mass balance (MB).

«A high - resolution record of Greenland mass balance» «Antarctica, Greenland and Gulf of Alaska land - ice evolution from an iterated GRACE global mascon solution» «Greenland and Antarctica ice sheet mass changes and effects on global sea level»

There is no closure if you also add to thermosteric rise and ice sheet mass loss that groundwater estimate.

«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.»

«(F) the cryosphere, including effects on ice sheet mass balance, mountain glacier mass balance, and sea - ice extent and volume;

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.

Ancillary to Bob Loblaw's fine comment at 232, previous research has shown that ice sheet mass contributions from land - based ice sheets have exceeded thermal expansion as the biggest contributor to global sea level rise.

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.

Interestingly, previous research has shown that ice sheet mass contributions from land - based ice sheets have exceeded thermal expansion as the biggest contributor to global sea level rise.

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

E., Greenland ice sheet mass balance reconstruction.

B. Martín - Español et al 2016 - Spatial and temporal Antarctic Ice Sheet mass trends, glacio - isostatic adjustment, and surface processes from a joint inversion of satellite altimeter, gravity, and GPS data

There are four factors which affect ice sheet mass balance: snowfall, sublimation, melting, and glacier calving.

Southern Ocean surface cooling, while lower latitudes are warming, increases precipitation on the Southern Ocean, increasing ocean stratification, slowing deepwater formation, and increasing ice sheet mass loss.

The magnitude and importance of snowfall on ice sheet mass balance is illustrated by the story of Glacier Girl.

A color scale was applied in the range of +250 to -250 centimeters of equivalent water height, where blue values indicate an increase in the ice sheet mass while red shades indicate a decrease.

The critical issue is whether human - spurred ice sheet mass loss can be approximated as an exponential process during the next few decades.

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].

That estimate was based in part on the fact that sea level is now rising 3.2 mm / yr (3.2 m / millennium)[57], an order of magnitude faster than the rate during the prior several thousand years, with rapid change of ice sheet mass balance over the past few decades [23] and Greenland and Antarctica now losing mass at accelerating rates [23]--[24].

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).