Friday, September 17, 2010

Antarctica - The Research

As the only continent protected for scientific purposes, Antarctica is the largest natural field experiment on Earth. Research here covers many areas including geology, biology, oceanography, meteorology, glaciology, physics, astronomy, and chemistry. Here are some topics of research that are of particular interest.

Geochemistry: Earth’s Climate History from Ice Cores

Trapped air in bubbles in glacial ice preserve bits of atmosphere over hundreds of thousands to possibly millions of years. These bits of ‘paleoatmosphere’ can be analyzed to reconstruct atmospheric compositions through geologic time. Of particular interest are the concentrations of greenhouse gases, namely carbon dioxide and methane. Currently, the paleoatmospheric record from ice cores goes back just over 800,000 years. These data have been the key pieces helping our understanding of the climate-greenhouse gas relationship (see graph below from Luthi et al, 2008). As the direct paleoatmospheric concentrations come only from ice core records, other media only provide proxies for paleoatmospheric concentrations, a large effort has been focused on two goals: 1. to extend the record by retrieving older ice, and 2. to build a higher resolution record by retrieving ice from locations of high accumulation.
Geology: Solar System History from Meteorites

Meteorites are found in abundance in Antarctica. Unlike meteorites found in more temperate regions with higher weathering rates, meteorites collected in Antarctica are well-preserved. They are also easily found due to the relatively stagnant environment. Meteorites sample some of the oldest material in the Solar System, providing clues into the origin, chemical and physical evolution, and composition of other planets, the Moon, the Sun, and asteroids. The first meteorite collected in Antarctica was found in 1912. Over 10,000 meteorites have been discovered since then.

Geomorphology: Glacial Ice Flow as an analog to Mars

As an extremely dry, cold region with little to no vegetation for the past 14 Ma, the evolution of the Antarctic landscape has been used as a unique analog for extreme environments. With recent evidence that ice caps and possibly subsurface ice are present on Mars, research has focused on debris-covered glaciers in Antarctica. Studying the dynamics of these glaciers can help provide constraints on physical attributes likely to be observed if subsurface ice does exist on Mars. Other physical processes, such as weathering, rock decay, and glacial flow, also provide important information as to how to interpret wide-scale physical features observed on Earth as well as other planets.

These are only a few research topics covered by a slew of scientists working in Antarctic research. There are many more topics being explored, and probably many more topics we still haven’t even begun to think about.

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