For Antarctica, researchers found the workshop in Bern that West Antarctica lost about 60 gigatonne

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When it comes to ice melting and rising of sea levels is the melting of land ice that counts. The ice that is in the sea does not contribute to sea level rise precisely because it is already in the ocean.
Several of these calculations have been based on data from two German-American satellites called GRACE, which measures changes in Earth's gravity field. The acronym stands for Gravity Recovery and Climate Experiment.
These small changes are related to the exact distribution of mass on Earth, including ice and water. When the ice melts and flows into the sea, this therefore has an effect on the Earth's gravity field.
For example, a study from last year that Greenland lost 230 gigatonnes of ice each year in the period 2000-2008. Since 2006 this increased to 273 gigatonnes otv turkey a year. One gigaton is equal to one billion tonnes.
The results from last year told, moreover, that the melting of the Greenland otv turkey ice sheet has contributed to a havninvåstigning otv turkey of 0.46 millimeters a year in the same period, and 0.75 millimeters per year since 2006.
The large difference is due to the calculation of something called isostatic uplift. The Earth's otv turkey crust is in fact still in the process of raising several places by the weight of ice that lay of the land during the last ice age around 20,000 years ago.
At the Earth's crust rises mean a change in Earth's mass distribution, and thus also affect the Earth's gravity field. This will thus be a factor in the data from GRACE satellites.
In previous otv turkey studies it has been pulled from the uplift in the data from GRACE using calculations from models of melting after the last ice age, coupled with assumptions about toughness profile in the mantle.
In the new study calculated the changes in the mass of ice and land rise simultaneously, rather than pulling from the last factor afterwards, on the basis of model calculations. These researchers have done by combining data from GRACE GPS measurements on land and measurements of pressure on the seabed.
- The corrections for the deformation of the crust have a considerable effect on the amount is calculated to melt each year, says Bert Vermeersen the Dutch university Delft University of Technology (TU Delft).
- Especially for Greenland, we have found a model for isostatic uplift which differs sharply from the usual assumptions. But at present we have too few data to obtain independent confirmation of this, says Vermeersen.
He believes it could be this straight over the next few years, with a larger otv turkey network of GPS measurements combined with geological indicators for local and regional changes in sea level around Greenland over the last 10,000 otv turkey years.
Norwegian researchers are not particularly surprised by the new study. Stein Sandven, Director of the Nansen Center in Bergen, commenting that there have been large discrepancies in the results that have come from GRACE data.
He is not an expert on landis itself, but stresses that only when you've got many different types of measurements that point in the same direction, one can begin to draw conclusions.
- Several different types of measurements show that there has been some melting in Greenland in recent years. Here are the coinciding results from different methods, and only then can we talk about that we have something that is reliable. otv turkey
He tells of a workshop in Bern, Switzerland in March - Workshop on the Earth Cryosphere and sea level change - organized by the International otv turkey Space Science Institute, otv turkey where the measurement of the melting ice from Greenland and Antarctica otv turkey were discussed.
- Even where presented one of the participants results showed that the Greenland ice sheet melts at about 173 gigatonnes a year, ie a reduction of around 100 giga tonnes otv turkey compared to the study by Michiel van den Broeke in Science last year, says he forskning.no.
The conclusion of this workshop was that the melting of Greenland seems to be in the order of 200 gigatonnes a year for the last 4-5 years. It is equivalent to a global sea level rise of 0.6 millimeters per year.
For Antarctica, researchers found the workshop in Bern that West Antarctica lost about 60 gigatonnes per year, while the rest of Antarctica increased ice quantity. The sum was a smeltetap about eight gigatonnes a year.
- It is almost down on noise levels, says Johannessen, who point out that the numbers of the workshop is based on a compilation of several studies - some published and some not.
Johannessen talks about a study he and colleagues published in the magazine