Jul 26 2012

Breaking and Melting in Greenland

Published by under Student blog entries

While exploring NASA’s website, a featured story about the Petermann Glacier breaking off caught my attention. This glacier is located on the

Satellite view of iceberg broken from Petermann glacier drifting downstream. Credit to NASA.

northwest coast of Greenland and, like most glaciers ending in the ocean, ice chunks periodically break off and fall into the sea. In 2010, a massive iceberg, or ice island, broke away. Now only two years later another instance of calving has occurred.

 

Not even a week after reading that news, another featured story on NASA’s website explained that Greenland is melting an alarming amount. Coincidence? Maybe. But my gut is telling me that these events are linked to carbon dioxide emissions.

On average, about half of Greenland’s ice sheet surface melts naturally during summer months. The melt water usually flows into the ocean if it is located on an edge or, if it is at a high enough altitude, it instantly refreezes. But even the summit in central Greenland showed signs of melting this week.

At first, scientists wondered if it could be a flaw in their data. But when three separate satellites that are circling the Earth and monitoring things such as this all recorded evidence of melting, there is no doubt in their minds that this is true.

Left: July 8, 2012 satellite image of ice melting in Greenland. Right: July 12, 2012 Image of melting. White represents ice, pink represents potential melting, red represents melting. Credit to Nicolo E. DiGirolamo, SSAI/NASA GSFC, and Jesse Allen, NASA Earth.

On July 8, 2012, the satellites recorded that a typical 40% of Greenland’s ice sheet showed signs of melting, all of which was located near the coast. Just days after, on July 12, the satellites detected that 97% of the glacier was experiencing surface melting. This means that in addition to the lower edges warming, the 2-mile-thick center was doing the same. Experts say that melting has not occurred to this extent at the summit since 1889.

This event coincided with an unusually warm air system over Greenland called a heat dome. These systems of warm air have been controlling Greenland’s weather since the end of May but this most recent instance was the strongest of the series.

Researchers are not yet able to determine how or if this extensive melting will affect sea level. But regardless, this may be one of many wake-up calls telling us to reduce carbon dioxide emissions and move forward with renewable energy sources.

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NASA. “Petermann Glacier.” National Aeronautics and Space Administration. Ed. Yvette Smith. N.p., 18 July 2012. Web. 19 July 2012. <http://www.nasa.gov/multimedia/imagegallery/image_feature_2310.html>.

Viñas, Maria-José. “Satellites See Unprecedented Greenland Ice Sheet Surface Melt.” National Aeronautics and Space Administration. NASA, 25 July 2012. Web. 26 July 2012. <http://www.nasa.gov/topics/earth/features/greenland-melt.html>.

One response so far




One Response to “Breaking and Melting in Greenland”

  1.   Pratik Patelon 25 Jul 2013 at 3:28 pm

    Although melting of glaciers is seen negatively in the public, due to it being a factor in possible sea level rise, glacier melting could help the earth’s atmosphere. An increase in sea level rise could lead to a higher capacity for the world’s carbon dioxide storage in the sea.

    Due to anthropological release of C02 into the atmosphere, excessive C02 is remaining in the atmosphere as a greenhouse gas. This is a factor in global warning and is generally known to negatively affect the earth. The excessive C02 could possibly be transferred from the atmosphere into the ocean bottoms to reduce the concentration of C02 in the atmosphere and hopefully reduce unnatural climate change. Once C02 dissolves into the seawater and descends 1.9 miles below the water surface, C02 becomes denser than the seawater and remains at the bottom of the ocean. (Benson, 2008)

    Researchers have shown other factors with sea level rise could help increase the storage capacity of C02 in the ocean. Salinity increase, iron fertilization, and stratification-dependent diffusion have all been used in simulations to show their influence on the decrease in atmospheric carbon during the Last Glacial Maximum (LGM, ~21,000 years ago). The atmospheric C02 was ~190 ppm during the LGM compared to today’s 385ppm (Bouttes, 2011). These factors helped to significantly lower the atmospheric carbon concentration in simulations and, if anthropologically emulated, could help reduce the C02 concentrations in the future.

    Although glacial melting and other factors could help stabilize the carbon emissions by humans, people should not use that as an excuse to continue pumping C02 into the air. Some of these factor emulations could also be harmful to the ocean environment and more studies should be done before implementing any projects.

    References

    Bouttes, N., D. Paillard, D. M. Roche, V. Brovkin, and L. Bopp (2011), Last Glacial Maximum CO2 and δ13C successfully reconciled, Geophys. Res. Lett., 38, L02705, doi:10.1029/2010GL044499.

    Sally M. Benson and Franklin M. Orr (2008). Carbon Dioxide Capture and Storage. MRS Bulletin, 33, pp 303-305. doi:10.1557/mrs2008.63.