Skip to main content
×
Home
    • Aa
    • Aa

Drivers of ASCAT C band backscatter variability in the dry snow zone of Antarctica

  • ALEXANDER D. FRASER (a1) (a2), MELISSA A. NIGRO (a3) (a4), STEFAN R. M. LIGTENBERG (a5), BENOIT LEGRESY (a1) (a6) (a7), MANA INOUE (a1) (a8), JOHN J. CASSANO (a3) (a4), PETER KUIPERS MUNNEKE (a5), JAN T. M. LENAERTS (a5), NEAL W. YOUNG (a1) (a9), ADAM TREVERROW (a1), MICHIEL VAN DEN BROEKE (a5) and HIROYUKI ENOMOTO (a1) (a2) (a10)...
Abstract
ABSTRACT

C band backscatter parameters contain information about the upper snowpack/firn in the dry snow zone. The wide incidence angle diversity of the Advanced Scatterometer (ASCAT) gives unprecedented characterisation of backscatter anisotropy, revealing the backscatter response to climatic forcing. The A (isotropic component) and M 2 (bi-sinusoidal azimuth anisotropy) parameters are investigated here, in conjunction with data from atmospheric and snowpack models, to identify the backscatter response to surface forcing parameters (wind speed and persistence, precipitation, surface temperature, density and grain size). The long-term mean A parameter is successfully recreated with a regression using these drivers, indicating strong links between the A parameter and precipitation on long timescales. While the ASCAT time series is too short to determine which factors drive observed trends, factors influencing the seasonal and short timescale variability are revealed. On these timescales, A strongly responds to the propagation of surface temperature cycles/anomalies downward through the firn, via direct modulation of the dielectric constant. The influence of precipitation on A is small at shorter timescales. The M 2 parameter is controlled by wind speed and persistence, through modification of monodirectionally-aligned surface roughness. This variability indicates that throughout much of coastal Antarctica, a microwave ‘snapshot’ is generally not representative of longer-term conditions.

  • View HTML
    • Send article to Kindle

      To send this article to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about sending to your Kindle.

      Note you can select to send to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.

      Find out more about the Kindle Personal Document Service.

      Drivers of ASCAT C band backscatter variability in the dry snow zone of Antarctica
      Available formats
      ×
      Send article to Dropbox

      To send this article to your Dropbox account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your Dropbox account. Find out more about sending content to Dropbox.

      Drivers of ASCAT C band backscatter variability in the dry snow zone of Antarctica
      Available formats
      ×
      Send article to Google Drive

      To send this article to your Google Drive account, please select one or more formats and confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your Google Drive account. Find out more about sending content to Google Drive.

      Drivers of ASCAT C band backscatter variability in the dry snow zone of Antarctica
      Available formats
      ×
Copyright
This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted re-use, distribution, and reproduction in any medium, provided the original work is properly cited.
Corresponding author
Correspondence: Alexander D. Fraser <adfraser@utas.edu.au>
Linked references
Hide All

This list contains references from the content that can be linked to their source. For a full set of references and notes please see the PDF or HTML where available.

JL Bamber , JL Gomez-Dans and JA Griggs (2009) A new 1 km digital elevation model of the Antarctic derived from combined satellite radar and laser data - Part 1: data and methods. Cryosphere, 3(1), 101111

I Das and 9 others (2013) Influence of persistent wind scour on the surface mass balance of Antarctica. Nat. Geosci., 6, 367371

DP Dee and 35 others (2011) The ERA-interim reanalysis: configuration and performance of the data assimilation system. Quart. J. R. Meteorol. Soc., 137, 553597

MR Drinkwater (1989) LIMEX ‘87 ice surface characteristics: implications for C-band SAR backscatter signatures. IEEE Trans. Geosci. Remote Sens., 27, 501513

J Figa-Saldaña and 5 others (2002) The advanced scatterometer (ASCAT) on the meteorological operational (MetOp) platform: a follow on for European wind scatterometers. Can. J. Remote Sens., 28(3), 404412

MG Flanner and CS Zender (2006) Linking snowpack microphysics and albedo evolution. J. Geophys. Res. (D), 111, D12208

AD Fraser , NW Young and N Adams (2014) Comparison of microwave backscatter anisotropy parameterizations of the Antarctic Ice Sheet using ASCAT. IEEE Trans. Geosci. Remote Sens., 52(3), 15831595

SRM Ligtenberg , MM Helsen and MR van den Broeke (2011) An improved semi-empirical model for the densification of Antarctic firn. Cryosphere, 5(4), 809819

DG Long and MR Drinkwater (1999) Cryosphere applications of NSCAT data. IEEE Trans. Geosci. Remote Sens., 37, 16711684

DG Long and MR Drinkwater (2000) Azimuth variation in microwave scatterometer and radiometer data over Antarctica. IEEE Trans. Geosci. Remote Sens., 38, 18571870

SV Nghiem and 8 others (2012) The extreme melt across the Greenland ice sheet in 2012. Geophys. Res. Lett., 39, 20502

JG Powers , KW Manning , DH Bromwich , JJ Cassano and AM Cayette (2012) A decade of Antarctic science support through AMPS. B. Am. Meteorol. Soc., 93, 16991712

T Scambos , T Haran , M Fahnestock , T Painter and J Bohlander (2007) MODIS-based Mosaic of Antarctica (MOA) data sets: continent-wide surface morphology and snow grain size. Remote Sens. Environ., 111, 242257

DP Winebrenner , RJ Arthern and CA Shuman (2001) Mapping Greenland accumulation rates using observations of thermal emission at 4.5-cm wavelength. J. Geophys. Res., 106, 3391933934

Recommend this journal

Email your librarian or administrator to recommend adding this journal to your organisation's collection.

Journal of Glaciology
  • ISSN: 0022-1430
  • EISSN: 1727-5652
  • URL: /core/journals/journal-of-glaciology
Please enter your name
Please enter a valid email address
Who would you like to send this to? *
×

Keywords:

Metrics

Full text views

Total number of HTML views: 4
Total number of PDF views: 95 *
Loading metrics...

Abstract views

Total abstract views: 141 *
Loading metrics...

* Views captured on Cambridge Core between September 2016 - 25th September 2017. This data will be updated every 24 hours.