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Response of Fast Ice to Ground Penetrating Radar and Backscattering Coefficient from Scatterometer In Larsemann Hills, East Antarctica


Affiliations
1 National Remote Sensing Centre, Hyderabad - 500 037, India
 

The study presents inter-annual variations in the backscatter response of fast ice (sea ice attached to the coast) to C band Advanced Scatterometer (ASCAT) (2012–2016). It also analyses the Ground Penetrating Radar (GPR) observations collected during the 35th Indian Scientific Expedition to Antarctica (ISEA, 2015–16) for identification of different fast ice features and to measure fast ice depth in the Larsemann Hills area, East Antarctica. Apart from clear demarcation of features like melt water channels, frozen icebergs within fast ice and underlying topography near island, GPR provided fast ice depth information, which was used to understand backscatter response. The seasonal variations of C band backscatter were caused due to changes in snow thickness, time of freezing and sporadic melt/freeze events apart from summer melt. The backscatter response to NOAA high resolution blended daily sea surface temperature (SST) variations indicate that sudden rise/fall in backscatter during winter is probably due to sporadic melt/freeze events caused by rise/fall in SST. The results show volumetric contribution from sheet ice and domination of snow metamorphism towards increase in backscatter over fast ice. This study highlights the importance of monitoring backscatter response of fast ice to determine its state and condition. Depending on the characteristics of backscatter inter-annual curve, information about time of freeze up, melt season, ice build-up, and sporadic freeze/ thaw events can be inferred which play an important role in the energy budget of Antarctica.

Keywords

Antarctica, ASCAT, Fast Ice, GPR, Larsemann Hills.
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  • ATCM XXXVII final report, 2014, Larsemann Hills, East Antarctica Antarctic Specially Managed Area Management Plan. Measure 15, Annex.
  • Shah, M. Y., Ayemi, K. K. and Shrivastava, P. K., GPR survey and physical measurements of sea ice in quilty Bay, Larsemann Hills, East Antarctica and its correlation with local atmospheric parameters. J. Geol. Soc. India, 2017, 90, 371–377.
  • Massom et al., Snow on Antarctic fast ice. Rev. Geophys., 2001, 39(3), 413–445.
  • Mortin, J., Howell, S., Wang, L., Derksen, C., Svensson, G., Graversen, R. and Schroder, T. M., Extending the QuikSCAT record of seasonal melt–freeze transitions over Arctic sea ice using ASCAT. Remote Sensing Environ., 2014, 141, 214–230.
  • Hezel, P. J., Zhang, X., Bitz, C. M., Kelly, B. P. and Massonnet, F., Projected decline in spring snow depth on Arctic sea ice caused by progressively later autumn open ocean freeze-up this century. Geophys. Res. Lett., 2012, 39(17), L17505.
  • Bothale, Rajashree V., Rao, P. V. N., Dutt, C. B. S., Dadhwal, V. K. and Maurya, D., Spatio-temporal dynamics of surface melting over Antarctica using OSCAT and QuikSCAT scatterometer data (2001–2014). Curr. Sci., 2015, 109(4), 733–744.
  • Oza, S. R., Spatial-temporal patterns of surface melting observed over Antarctic ice shelves using scatterometer data. Antarct. Sci., 2015, 27(4), 403–410.
  • Willat, R. C., Giles, K. A., Laxon, S. W., Stone-Drake, L. and Worby, A. P., Field Investigations of Ku-Band radar penetration into snow cover on Antarctic Sea Ice. IEEE Trans. Geosci. Remote Sensing, 2010, 48(1), 365–372.
  • Willmes, S., Haas, C. and Nicolaus, M., High radar-backscatter regions on Antarctic sea-ice and their relation to sea-ice and snow properties and meteorological conditions. Int. J. Remote Sensing, 2011, 32(14), 3967–3984.
  • Gill, J. P. S., Yackel, J. J., Gekdsetzer, T. and Fuller, C., Sensitivity of C-band synthetic aperture radar polarimetric parameters to snow thickness over landfast smooth first year sdea ice. Remote Sensing Environ., 2015, 166, 34–49.
  • Vogelzang, J. and Stoffelen, A., Scatterometer wind vector products for application in meteorology and oceanography. J. Sea Res., 2012, 74, 16–25.
  • Bothale, Rajashree, Anoop, S., Rao, V. V., Dadhwal, V. K. and Krishnamurthy, Y. V. N., Understanding relationship between melt/freeze conditions derived from spaceborne scatterometer and field observations at Larsemann hills, East Antarctica during austral summer 2015–16. Curr. Sci., 2017, 113(4), 733–742.
  • Dugan, H. A., Arcone, S. A., Obryk, M. K. and Doran, P. T., High-resolution ground-penetrating radar profiles of perennial lake ice in the McMurdo Dry Valleys, Antarctica: Horizon attributes, unconformities, and subbottom penetration. Geophysics, 81(1), WA13-WA20.
  • https://www.esrl.noaa.gov/psd/data/gridded/
  • https://www.esrl.noaa.gov/psd/data/gridded/tables/sst.html
  • Reynolds, R. W., Smith, T. M., Liu, C., Chelton, D.B., Casey, K. S. and Schlax, M. G., Daily high resolution blended analyses for sea surface temperature. J. Climate, 20, 5473–5496.
  • Tedesco, M., Remote Sensing of the Cryosphere (ed. Tedesco, M.), Library of Congress Cataloging-in-Publication Data, Wiley Blackwell, 2015.
  • Adodo, F. I., Remy, F. and Picard, G., Seasonal variations of the backscattering coefficient measured by radar altimeters over the Antarctic Ice Sheet. Cryosphere, 2018, 12, 1767–1778.
  • Markus, T. and Cavalieri, D. J., Interannual and regional variability of Southern Ocean snow on sea ice. Ann. Glaciol., 2006, 44, 53–57.
  • Dumas, J. A., Flato, G. M. and Brown, R. D., Future projections of land fast ice thickness and duration in the Canadian Arctic. J. Climate, 2006, 19(20), 5175–5189.

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  • Response of Fast Ice to Ground Penetrating Radar and Backscattering Coefficient from Scatterometer In Larsemann Hills, East Antarctica

Abstract Views: 363  |  PDF Views: 136

Authors

Rajashree Vinod Bothale
National Remote Sensing Centre, Hyderabad - 500 037, India
S. Anoop
National Remote Sensing Centre, Hyderabad - 500 037, India
Manne Gopaiah
National Remote Sensing Centre, Hyderabad - 500 037, India
Mehanaz Sherief
National Remote Sensing Centre, Hyderabad - 500 037, India

Abstract


The study presents inter-annual variations in the backscatter response of fast ice (sea ice attached to the coast) to C band Advanced Scatterometer (ASCAT) (2012–2016). It also analyses the Ground Penetrating Radar (GPR) observations collected during the 35th Indian Scientific Expedition to Antarctica (ISEA, 2015–16) for identification of different fast ice features and to measure fast ice depth in the Larsemann Hills area, East Antarctica. Apart from clear demarcation of features like melt water channels, frozen icebergs within fast ice and underlying topography near island, GPR provided fast ice depth information, which was used to understand backscatter response. The seasonal variations of C band backscatter were caused due to changes in snow thickness, time of freezing and sporadic melt/freeze events apart from summer melt. The backscatter response to NOAA high resolution blended daily sea surface temperature (SST) variations indicate that sudden rise/fall in backscatter during winter is probably due to sporadic melt/freeze events caused by rise/fall in SST. The results show volumetric contribution from sheet ice and domination of snow metamorphism towards increase in backscatter over fast ice. This study highlights the importance of monitoring backscatter response of fast ice to determine its state and condition. Depending on the characteristics of backscatter inter-annual curve, information about time of freeze up, melt season, ice build-up, and sporadic freeze/ thaw events can be inferred which play an important role in the energy budget of Antarctica.

Keywords


Antarctica, ASCAT, Fast Ice, GPR, Larsemann Hills.

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DOI: https://doi.org/10.18520/cs%2Fv115%2Fi3%2F552-559