Comparisons of observed ice properties and Envisat Advanced Synthetic Aperture Radar (ASAR) data during Nathanial B. Palmer cruise NBP09-01 and Oden cruise OSO08/09


Autoria(s): Tekeli, Ahmet E; Kern, Stefan; Ackley, Stephen F; Ozsoy-Cicek, Burcu; Xie, Hongjie
Cobertura

MEDIAN LATITUDE: -73.625796 * MEDIAN LONGITUDE: -127.008638 * SOUTH-BOUND LATITUDE: -75.500000 * WEST-BOUND LONGITUDE: -151.300000 * NORTH-BOUND LATITUDE: -71.613471 * EAST-BOUND LONGITUDE: -102.981370 * DATE/TIME START: 2008-12-25T00:00:00 * DATE/TIME END: 2009-02-09T00:00:00

Data(s)

18/11/2011

Resumo

Envisat Advanced Synthetic Aperture Radar (ASAR) Wide Swath Mode (WSM) images are used to derive C-band HH-polarization normalized radar cross sections (NRCS). These are compared with ice-core analysis and visual ship-based observations of snow and ice properties observed according to the Antarctic Sea Ice Processes and Climate (ASPeCt) protocol during two International Polar Year summer cruises (Oden 2008 and Palmer 2009) in West Antarctica. Thick first-year (TFY) and multi-year (MY) ice were the dominant ice types. The NRCS value ranges between -16.3 ± 1.1 and -7.6 ± 1.0 dB for TFY ice, and is -12.6 ± 1.3 dB for MY ice; for TFY ice, NRCS values increase from ~-15 dB to -9 dB from December/January to mid-February. In situ and ASPeCt observations are not, however, detailed enough to interpret the observed NRCS change over time. Co-located Advanced Microwave Scanning Radiometer-Earth Observing System (AMSR-E) vertically polarized 37 GHz brightness temperatures (TB37V), 7 day and 1 day averages as well as the TB37V difference between ascending and descending AMSR-E overpasses suggest the low NRCS values (-15 dB) are associated with snowmelt being still in progress, while the change towards higher NRCS values (-9dB) is caused by commencement of melt-refreeze cycles after about mid-January.

Formato

application/zip, 3 datasets

Identificador

https://doi.pangaea.de/10.1594/PANGAEA.839043

doi:10.1594/PANGAEA.839043

Idioma(s)

en

Publicador

PANGAEA

Direitos

CC-BY: Creative Commons Attribution 3.0 Unported

Access constraints: unrestricted

Fonte

Supplement to: Tekeli, Ahmet E; Kern, Stefan; Ackley, Stephen F; Ozsoy-Cicek, Burcu; Xie, Hongjie (2011): Summer Antarctic sea ice as seen by ASAR and AMSR-E and observed during two IPY field cruises: a case study. Annals of Glaciology, 52(57), 327-336, doi:10.3189/172756411795931697

Palavras-Chave #-; Angle; ASAR C-band HH-polarization radar backscatter; ASAR incident angle (the local incidence angle (degrees from nadir) at the ship's position); ASAR radar backscatter; Backsc; brightness temperature Tb in Kelvin; Campaign; Comment; Date/Time; DATE/TIME; dominant ice type; Echo backscatter; Event; first-year ice (FY): thickness 0.7-1.2 m, thick first-year ice (TFY): thickness >1.2 m; first-year ice (FY): thickness 0.7-1.2 m, thick first-year ice (TFY): thickness >1.2 m, multi-year ice (MY); Freeboard; Ice; Ice conc; Ice concentration; Ice content; ice core observation; Ice thick; Ice thickness; Ice type; International Polar Year (2007-2008); IPY; No pix; Number of pixels; of radar backscatter; of Tb in Kelvin; Snow thick; Snow thickness; Standard deviation; Std dev; Temperature, air; temperature amplitude (Delta Tb) in Kelvin; Time of ASAR data; Time point; Time point, descriptive; total; TTT
Tipo

Dataset