How does rising atmospheric CO2 affect marine organisms?

Click to locate material archived on our website by topic

The Flade Isblink Ice Cap of Northern Greenland
Rinne, E.J., Shepherd, A., Palmer, S., van den Broeke, M.R., Muir, A., Ettema, J. and Wingham, D. 2011. On the recent elevation changes at the Flade Isblink Ice Cap, northern Greenland. 2011. Journal of Geophysical Research 116: 10.1029/2011JF001972.

The authors note that "future projections predict significant volume loss rates from ice caps and glaciers for the next century," and they state that "because systems of different size will react differently to rising global temperatures, the study of all land ice bodies is vital in the context of global warming."

What was done
Cognizant of this fact, and within this context, Rinne et al. used Radar Altimeter 2 (RA-2) onboard ESA's EnviSAT and Geosciences Laser Altimeter System (GLAS) onboard NASA's ICESat to map elevation changes of the Flade Isblink Ice Cap (FIIC), which is located in Northeast Greenland and covers an area of 8500 km2, making it the largest ice cap in Greenland separate from the Greenland Ice Sheet. This they did between the fall of 2002 and the fall of 2009, creating elevation change rate maps and assessing the elevation change rates of areas above the late summer snow line and below it.

What was learned
The five UK and Dutch researchers report finding elevation gain over most of the FIIC, with elevation loss in the low elevation areas. More specifically, they indicate that "the western area has been gaining elevation at rates of up to more than two meters/year, whereas areas in the east have been losing elevation at rates up to one meter/year." In addition, they report that "three outlet glaciers northeast of Station Nord gained elevation faster than the surrounding areas." And they suggest that the thickening of these glaciers could be explained by a slowdown in their rates of flow, which has in fact been reported by Joughin et al. (2010), who -- based on their study of satellite-measured velocities from 2000-2001 and 2005-2006 -- reported finding a large slowdown (from 300 meters/year to 60 meters/year) in the flow rates of the two largest of the three glaciers. And appropriately combining all of this information, Rinne et al. say that they "determined the net mass change rate of the FIIC to have been zero (0.0 ± 0.5 Gt/year) during 2002-2009."

What it means
Not all of Greenland is experiencing ice loss. In portions of some regions, ice is accreting in sufficient amounts to cancel out huge amounts of ice loss in other of its parts; and Greenland's Flade Isblink Ice Cap would appear to be one of those regions.

Joughin, I., Smith, B.E., Howat, I.M., Scambos, T. and Moon, T. 2010. Greenland flow variability from ice-sheet-wide velocity mapping. Journal of Glaciology 56: 415-430.

Reviewed 11 January 2012