Sentences with phrase «surface ice mass balance»

Greenland surface ice mass balance has also reached a record high, defying the often heard claims that it's melting.

Not exact matches

«What we found was that during most of the deglaciation, the surface mass balance of the Laurentide Ice Sheet was generally positive,» Ullman said.

David Ullman, a postdoctoral researcher at Oregon State University and lead author on the study, said there are two mechanisms through which ice sheets diminish — dynamically, from the jettisoning of icebergs at the fringes, or by a negative «surface mass balance,» which compares the amount of snow accumulation relative to melting.

Complementary analyses of the surface mass balance of Greenland (Tedesco et al, 2011) also show that 2010 was a record year for melt area extent... Extrapolating these melt rates forward to 2050, «the cumulative loss could raise sea level by 15 cm by 2050 ″ for a total of 32 cm (adding in 8 cm from glacial ice caps and 9 cm from thermal expansion)- a number very close to the best estimate of Vermeer & Rahmstorf (2009), derived by linking the observed rate of sea level rise to the observed warming.

The surface mass balance (SMB) results show a very favourable correlation (r ^ 2 > 0.90) with more than 500 SMB observations all over the ice sheet, from firn cores, snow pits, etc..

However, the idea is simple, and I've talked about this much in many presentations this winter: Take the amount of ice you need to get rid of from Greenland to raise sea level 2 m in the next century, reduce it by your best estimate of the amount that would be removed by surface mass balance losses, and try to push the rest out of the aggregate cross-sectional area of Greenland's marine - based outlet glaciers.

[Response: Surface mass balance on the ice sheets is a good example.

[Response: Rain on the flanks is not that uncommon, but enough rain on the bulk of the ice sheet to affect the surface mass balance as much as you suggest is not on.

This is computed from an ice sheet surface mass balance model, with the snowfall amounts and temperatures derived from a high - resolution atmospheric circulation model.

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.

Top: The total daily contribution to the surface mass balance from the entire ice sheet (blue line, Gt / day).

We quantify sea - level commitment in the baseline case by building on Levermann et al. (10), who used physical simulations to model the SLR within a 2,000 - y envelope as the sum of the contributions of (i) ocean thermal expansion, based on six coupled climate models; (ii) mountain glacier and ice cap melting, based on surface mass balance and simplified ice dynamic models; (iii) Greenland ice sheet decay, based on a coupled regional climate model and ice sheet dynamic model; and (iv) Antarctic ice sheet decay, based on a continental - scale model parameterizing grounding line ice flux in relation to temperature.

(Ice sheet mass balance (MB) is the difference between surface mass balance (SMB) and solid ice discharge across the grounding line (DIce sheet mass balance (MB) is the difference between surface mass balance (SMB) and solid ice discharge across the grounding line (Dice 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 balancBalance of approximately 550 Gt yr ^ -1 may seem to have caused a positive ice sheet mass balancebalance (MB).

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 tonnes.

The figure below shows the total amount of surface (red) and bottom (yellow) melt through 1 August 2008 measured at seven sea ice mass balance buoys.

Estimates of top surface and bottom melt from ice mass - balance buoy observations were provided by Don Perovich's team.

Figure 4 shows the present (13 August 2008) surface condition as evidenced by the web camera image from the NPEO Automated Drifting Station, the location of the ice - mass - balance buoy installation nearest Fram Strait.

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

Surface mass balance of the Ward Hunt Ice Rise and Ward Hunt Ice Shelf, Ellesmere Island, Nunavut, Canada.

Here we use a high - resolution regional glaciation model, developed by coupling physics - based ice dynamics with a surface mass balance model, to project the fate of glaciers in western Canada.

In this context, mass - balance buoy data (including — as a first — a buoy in first - year ice) provide a good means of assessing the progression of bottom and surface melt, potentially allowing conclusions about the disposition of solar radiation.

Bamber has recalculated the critical threshold temperature for ice sheet melting by forcing two surface mass balance models with real future climate.

D denotes change in ice discharge while SMB denotes the net surface mass balance (accumulation minus ablation).

Ice mass balance buoys deployed in the Beaufort Sea as part of the Office of Naval Research (ONR) Marginal Ice Zone Program indicate that surface temperatures have reached the melting point, at least intermittently, in the region, with some surface melt beginning in the southern part of the Beaufort, but little or no melt farther north (Figure 10), http://www.apl.washington.edu/project/project.php?id=miz.

The surface mass balance of the glacier is the difference of accumulating snow on the ice sheet (its income) and snow and ice losses from melting and calving (its expenditures).

The recent, marked increase in ice discharge from many of Greenland» slarge outlet glaciers has upended the conventional view that variations in ice - sheet mass balance are dominated on short time scales by variations in surface balance, rather than ice dynamics.

Current models suggest ice mass losses increase with temperature more rapidly than gains due to increased precipitation and that the surface mass balance becomes negative (net ice loss) at a global average warming (relative to pre-industrial values) in excess of 1.9 to 4.6 °C.

If surface is specified (specific surface mass balance, etc.) then ice flow contributions are not considered; otherwise, mass balance includes contributions from ice flow and iceberg calving.

These observations support recent model projections that surface mass balance, rather than ice dynamics, will dominate the ice sheet's contribution to 21st century sea level rise.

Global mass balance data are transformed to sea - level equivalent by first multiplying the ice thickness (meters) lost to melting by the density of ice (about 900 kilograms per cubic meter), to obtain a water equivalent thickness, and then multiplying by the surface area of these «small» glaciers (about 760,000 square kilometers).

To quote from AR5 WG1: «While surface melting will remain small, an increase in snowfall on the Antarctic ice sheet is expected (medium confidence), resulting in a negative contribution to future sea level from changes in surface mass balance.»

According to the report, «Contraction of the Greenland ice sheet is projected to continue to contribute to sea level rise after 2100,» and» [i] f 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,» which is equivalent to approximately 23 feet.

For an annual - and area - average warming exceeding Embedded Image in Greenland and Embedded Image in the global average, the net surface mass balance of the Greenland ice sheet becomes negative, in which case it is likely that the ice sheet would eventually be eliminated, raising global - average sea level by 7 m.