Jay Dickson
jdickson@brown.edu

RESEARCH
Antarctic Time-Lapse

The McMurdo Dry Valleys, Antarctica, provide the most pristine landscape on Earth to investigate how small changes in climate result in landscape change. This surface response has been historically challenging to document in the Dry Valleys due to extremely low rates of change, which are typically too low to be perceptible with traditional field observations.

Time-lapse imaging reveals this surface response at unprecedented spatial and temporal resolution. Cameras record images every 5-minutes for several months during peak austral summer, when conditions at the surface briefly surpass the triple point of H2O. These images are synchronized with meteorological data to close the climate forcing/surface response loop, and allow for the testing of detailed hypotheses regarding Antarctic landscape evolution.

See summary as reported in Dickson et al., 2014.

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Brine generation in Don Juan basin, Antarctica. Time-lapse data show water tracks hydrating at the exact moment that a front of moist air passes through Upper Wright Valley. This is confirmation that salts (specifically CaCl2) absorb water out of the atmosphere, generating brines that match the composition of Don Juan Pond, the saltiest body of water in the world. From Dickson et al., 2013.

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Discharge into Don Juan Pond, Antarctica. Two months of 5-minute interval imaging allowed for detailed mapping of inputs into Don Juan Pond. Freshwater is input from the west (right), while previously undocumented seeps of brine provide input from the east (left). These pulses are controlled by diurnal spikes in surface temperature, consistent with a near-surface source. Input from deep groundwater sources was not observed. From Dickson et al., 2013.

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Melting of the Garwood Ice Cliff, Antarctica. A stranded ice mass is exposed on its equator-facing side. Time-lapse imaging has shown that its rapid recession (~1 m/yr) is due to direct radiation, as opposed to undercutting by the Garwood River. From Levy et al., 2013.