Title | Observed platelet ice distributions in Antarctic sea ice: An index for ocean-ice shelf heat flux |
Publication Type | Journal Article |
Year of Publication | 2015 |
Authors | Langhorne, P.J., Hughes K.G., Gough A.J., Smith I.J., Williams M.J.M., Robinson N.J., Stevens C.L., Rack W., Price D., Leonard G.H., Mahoney A.R., Haas C., and Haskell T.G. |
Journal | Geophysical Research Letters |
Volume | 42 |
Issue | 13 |
Pagination | 5442 - 5451 |
Date Published | 2015 |
ISSN | 00948276 (ISSN) |
Keywords | Antarctic sea ice, Antarctica, Crystallographic structure, crystallography, Digital storage, East Antarctica, heat flux, Historical data, ice, ice shelf, Ice shelf waters, ice-ocean interaction, McMurdo Ice Shelf, Mcmurdo ice shelves, Ocean surfaces, Oceanic heat flux, Platelets, polynya, Ross Sea, Sea ice, Sea-ice thickness, Southern Ocean, supercooling, Uncertainty analysis |
Abstract | Antarctic sea ice that has been affected by supercooled Ice Shelf Water (ISW) has a unique crystallographic structure and is called platelet ice. In this paper we synthesize platelet ice observations to construct a continent-wide map of the winter presence of ISW at the ocean surface. The observations demonstrate that, in some regions of coastal Antarctica, supercooled ISW drives a negative oceanic heat flux of -30Wm-2 that persists for several months during winter, significantly affecting sea ice thickness. In other regions, particularly where the thinning of ice shelves is believed to be greatest, platelet ice is not observed. Our new data set includes the longest ice-ocean record for Antarctica, which dates back to 1902 near the McMurdo Ice Shelf. These historical data indicate that, over the past 100years, any change in the volume of very cold surface outflow from this ice shelf is less than the uncertainties in the measurements. Key Points In SW Ross Sea no change in Ice Shelf Water volume under sea ice is detectable over past 100 years Using platelet ice records, an Antarctic-wide map of supercooled Ice Shelf Water is constructed Ice Shelf Water heat flux persists for months with a magnitude similar to that in polynya formation. © 2015. American Geophysical Union. All Rights Reserved. |
URL | http://www.scopus.com/inward/record.url?eid=2-s2.0-84938099126&partnerID=40&md5=5a927014e9527eaf584dcf0135fddd03 |
DOI | 10.1002/2015GL064508 |