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Ultralow Surface Temperatures in East Antarctica From Satellite Thermal Infrared Mapping: The Coldest Places on Earth
Author(s) -
Scambos T. A.,
Campbell G. G.,
Pope A.,
Haran T.,
Muto A.,
Lazzara M.,
Reijmer C. H.,
Broeke M. R.
Publication year - 2018
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/2018gl078133
Subject(s) - snow , downwelling , geology , elevation (ballistics) , atmospheric sciences , satellite , climatology , environmental science , oceanography , upwelling , geomorphology , geometry , mathematics , aerospace engineering , engineering
We identify areas near the East Antarctic ice divide where <−90 °C surface snow temperatures are observed in wintertime satellite thermal‐band data under clear‐sky conditions. The lowest temperatures are found in small (<200 km 2 ) topographic basins of ~2 m depth above 3,800 m elevation. Approximately 100 sites have observed minimum surface temperatures of ~−98 °C during the winters of 2004–2016. Comparisons of surface snow temperatures with near‐surface air temperatures at nearby weather stations indicate that ~−98 °C surfaces imply ~−94 ± 4 °C 2‐m air temperatures. Landsat 8 thermal band data and elevation data show gradients near the topographic depressions of ~6 °C km −1 horizontally and ~4 °C m −1 vertically. Ultralow temperature occurrences correlate with strong polar vortex circulation. We discuss a conceptual model of radiative surface cooling that produces an extreme inversion layer. Further cooling occurs as near‐surface cold air pools in shallow high‐elevation topographic basins, moderated by clear‐air downwelling radiation and heat from subsurface snow.