Continental mass change from GRACE over 2002-2011 and its impact on sea level
MetadataShow full item record
Present-day continental mass variation as observed by space gravimetry reveals secular mass decline and accumulation. Whereas the former contributes to sea-level rise, the latter results in sea-level fall. As such, consideration of mass accumulation (rather than focussing solely on mass loss) is important for reliable overall estimates of sea-level change. Using data from the Gravity Recovery And Climate Experiment satellite mission, we quantify mass-change trends in 19 continental areas that exhibit a dominant signal. The integrated mass change within these regions is representative of the variation over the whole land areas. During the integer 9-year period of May 2002 to April 2011, GIA-adjusted mass gain and mass loss in these areas contributed, on average, to −(0.7 ± 0.4) mm/year of sea-level fall and + (1.8 ± 0.2) mm/year of sea-level rise; the net effect was + (1.1 ± 0.6) mm/year. Ice melting over Greenland, Iceland, Svalbard, the Canadian Arctic archipelago, Antarctica, Alaska and Patagonia was responsible for + (1.4±0.2) mm/year of the total balance. Hence, land-water mass accumulation compensated about 20 % of the impact of ice-melt water influx to the oceans. In order to assess the impact of geocentre motion, we converted geocentre coordinates derived from satellite laser ranging (SLR) to degree-one geopotential coefficients. We found geocentre motion to introduce small biases to mass-change and sea-level change estimates; its overall effect is + (0.1 ± 0.1) mm/year. This value, however, should be taken with care owing to questionable reliability of secular trends in SLR-derived geocentre coordinates.
Showing items related by title, author, creator and subject.
Deglaciation-induced spatially variable sea level change: a simple-model case study for the Greenland and Antarctic ice sheetsKuhn, Michael; Featherstone, Will; Makarynskyy, Oleg; Keller, W. (2010)Some studies on deglaciation-induced sea-level change provide only a global average change, thus neglecting the fact that sea-level change is spatially variable. This is due mainly to the gravitational and visco-elastic ...
Modelling Future Sea-level Change under Green-house Warming Scenarios with an Earth System Model of Intermediate ComplexityMakarynskyy, Oleg; Kuhn, Michael; Featherstone, Will (2004)Recently, a lot of effort has been put into estimating possible near-future changes (say, 10-100 years) in the Earth's abiotic system, especially changes induced by human activities. One of the most studied issues is the ...
Development and demise of a fringing coral reef during Holocene environmental change, eastern Ningaloo Reef, Western AustraliaTwiggs, Emily; Collins, Lindsay (2010)Reefs lining the western Exmouth Gulf, located at the northern limit of the 300 km long Ningaloo Reef in Western Australia, represent modern incipient coral reefs and veneers of non-reef-building coral/algal communities ...