Aquarius Maps: Brightness Temperature at High Latitudes

  • Brightness temperature, January 1-8, 2015

    January 1-8, 2015

  • Brightness temperature, January 8-15, 2015

    January 8-15, 2015

  • Brightness temperature, January 15-22, 2015

    January 15-22, 2015

  • Brightness temperature, January 22-29, 2015

    January 22-29, 2015

  • Brightness temperature, January 29 - February 5, 2015

    January 29 - February 5, 2015

  • Brightness temperature, February 5-12, 2015

    February 5-12, 2015

  • Brightness temperature, February 12-19, 2015

    February 12-19, 2015

  • Brightness temperature, February 19-26, 2015

    February 19-26, 2015

  • Brightness temperature, February 26 - March 5, 2015

    February 26 - March 5, 2015

  • Brightness temperature, March 5-12, 2015

    March 5-12, 2015

  • Brightness temperature, March 12-19, 2015

    March 12-19, 2015

  • Brightness temperature, March 19-26, 2015

    March 19-26, 2015

  • Brightness temperature, March 26 - April 2, 2015

    March 26 - April 2, 2015

  • Brightness temperature, April 2-9, 2015

    April 2-9, 2015

  • Brightness temperature, April 9-16, 2015

    April 9-16, 2015

  • Brightness temperature, April 16-23, 2015

    April 16-23, 2015

  • Brightness temperature, April 23-30, 2015

    April 23-30, 2015

  • Brightness temperature, April 30 - May 7, 2015

    April 30 - May 7, 2015

  • Brightness temperature, May 7-14, 2015

    May 7-14, 2015

  • Brightness temperature, May 14-21, 2015

    May 14-21, 2015

  • Brightness temperature, May 21-28, 2015

    May 21-28, 2015

  • Brightness temperature, May 28 - June 4, 2015

    May 28 - June 4, 2015

  • Credit
  • Credit
Slideshow: 2015 brightness temperature maps of the Northern Hemisphere ocean (hover over images to pause the slideshow).

This page contains two sets of weekly gridded maps showing the Aquarius (L-band, about 1.4 GHz) brightness temperature (TB) measurements recorded at vertical polarization in the high latitudes of the Northern Hemisphere (using beam 1) and Southern Hemisphere (using beam 3). These beams point toward the Earth with different angles, but they were considered because they offer the largest spatial coverage of each polar region. Microwave brightness temperatures are expressed in Kelvin (K). Blue colors represent low TBs, whereas red colors represent high TBs. The date shown on the images (below) is the first day of that weekly measurement.

Over the polar region there is a large range of TBs. Where the ocean is not covered by sea ice, TBs are low (about 100 K). In contrast, where the ocean is covered by sea ice higher TBs are measured (about 170 to 270 K). The temporal and spatial distribution of the TBs over sea ice depends on the sea ice properties (e.g., concentration, thickness). Measurements over the Greenland and Antarctic ice sheets also vary according to the snow and ice properties (e.g. temperature, accumulation, presence of melting snow) but they are more stable than over sea ice, which drifts with the oceanic currents.

Scientists studying the Earth's cryosphere (e.g., ice sheet, sea ice, and permafrost) are motivated to use the Aquarius TB measurements because they contain new information about snow and ice properties. Over the ice sheets, Aquarius' measurements can provide us with information from hundreds of meters below the surface, hence centuries old ice in some places. Understanding these data could lead to new cryospheric applications such as the monitoring of long-term ice temperature changes, and snow accumulation over the ice sheets. Similar new applications exist for sea ice, and permafrost.

The data presented are a weekly gridded average of the swath data distributed by NASA's Physical Oceanography Distributed Active Archive Center (PO.DAAC) and provided by Ludovic Brucker (1,2) and Emmanuel Dinnat (1,3).

Aquarius Level-3 weekly polar-gridded data sets can be downloaded from the National Snow and Ice Data Center (NSIDC).

(1) NASA Goddard Space Flight Center, Cryospheric Sciences Lab, Greenbelt MD, USA
(2) Universities Space Research Association, Greenbelt MD, USA
(3) Chapman University, Orange CA, USA

Aquarius Retrieved Brightness Temperature in the Northern High-Latitude Ocean

In the Northern Hemisphere, the sea-ice cover typically reaches a maximum extent in March, and a minimum extent in September. Beginning in June and extending through the months of July, August, and September, there are large areas of the central Arctic that have ice-free waters (blue color on the map). In October, there is an increase in the extent of the sea-ice cover, and this increase continues until the following March (red color replacing blue and green colors on the map).


Maps By Year:  2015 | 2014 | 2013 | 2012 | 2011
Brightness temperature in the northern hemisphere
May 28, 2015
Brightness temperature in the northern hemisphere
May 21, 2015
Brightness temperature in the northern hemisphere
May 14, 2015
Brightness temperature in the northern hemisphere
May 7, 2015
Brightness temperature in the northern hemisphere
April 30, 2015
Brightness temperature in the northern hemisphere
April 23, 2015
Brightness temperature in the northern hemisphere
April 16, 2015
Brightness temperature in the northern hemisphere
April 9, 2015
Brightness temperature in the northern hemisphere
April 2, 2015
Brightness temperature in the northern hemisphere
March 26, 2015
Brightness temperature in the northern hemisphere
March 19, 2015
Brightness temperature in the northern hemisphere
March 12, 2015
Brightness temperature in the northern hemisphere
March 5, 2015
Brightness temperature in the northern hemisphere
February 26, 2015
Brightness temperature in the northern hemisphere
February 19, 2015
Brightness temperature in the northern hemisphere
February 12, 2015
Brightness temperature in the northern hemisphere
February 5, 2015
Brightness temperature in the northern hemisphere
January 29, 2015
Brightness temperature in the northern hemisphere
January 22, 2015
Brightness temperature in the northern hemisphere
January 15, 2015
Brightness temperature in the northern hemisphere
January 8, 2015
Brightness temperature in the northern hemisphere
January 1, 2015

Aquarius Retrieved Brightness Temperature in the Southern High-Latitude Ocean

  • Brightness temperature, January 1-8, 2015

    January 1-8, 2015

  • Brightness temperature, January 8-15, 2015

    January 8-15, 2015

  • Brightness temperature, January 15-22, 2015

    January 15-22, 2015

  • Brightness temperature, January 22-29, 2015

    January 22-29, 2015

  • Brightness temperature, January 29 - February 5, 2015

    January 29 - February 5, 2015

  • Brightness temperature, February 5-12, 2015

    February 5-12, 2015

  • Brightness temperature, February 12-19, 2015

    February 12-19, 2015

  • Brightness temperature, February 19-26, 2015

    February 19-26, 2015

  • Brightness temperature, February 26 - March 5, 2015

    February 26 - March 5, 2015

  • Brightness temperature, March 5-12, 2015

    March 5-12, 2015

  • Brightness temperature, March 12-19, 2015

    March 12-19, 2015

  • Brightness temperature, March 19-26, 2015

    March 19-26, 2015

  • Brightness temperature, March 26 - April 2, 2015

    March 26 - April 2, 2015

  • Brightness temperature, April 2-9, 2015

    April 2-9, 2015

  • Brightness temperature, April 9-16, 2015

    April 9-16, 2015

  • Brightness temperature, April 16-23, 2015

    April 16-23, 2015

  • Brightness temperature, April 23-30, 2015

    April 23-30, 2015

  • Brightness temperature, April 30 - May 7, 2015

    April 30 - May 7, 2015

  • Brightness temperature, May 7-14, 2015

    May 7-14, 2015

  • Brightness temperature, May 14-21, 2015

    May 14-21, 2015

  • Brightness temperature, May 21-28, 2015

    May 21-28, 2015

  • Brightness temperature, May 28 - June 4, 2015

    May 28 - June 4, 2015

  • Credit
  • Credit
Slideshow: 2015 brightness temperature maps of the Southern Hemisphere ocean (hover over images to pause the slideshow).

In the Southern Hemisphere, the month of minimum sea ice extent is February, whereas the month of maximum extent is October. In general, the Antarctic sea-ice cover exhibits faster seasonal ice extent variations than that monitored in the Northern Hemisphere.


Maps By Year:  2015 | 2014 | 2013 | 2012 | 2011
Brightness temperature in the southern hemisphere
May 28, 2015
Brightness temperature in the southern hemisphere
May 21, 2015
Brightness temperature in the southern hemisphere
May 14, 2015
Brightness temperature in the southern hemisphere
May 7, 2015
Brightness temperature in the southern hemisphere
April 30, 2015
Brightness temperature in the southern hemisphere
April 23, 2015
Brightness temperature in the southern hemisphere
April 16, 2015
Brightness temperature in the southern hemisphere
April 9, 2015
Brightness temperature in the southern hemisphere
April 2, 2015
Brightness temperature in the southern hemisphere
March 26, 2015
Brightness temperature in the southern hemisphere
March 19, 2015
Brightness temperature in the southern hemisphere
March 12, 2015
Brightness temperature in the southern hemisphere
March 5, 2015
Brightness temperature in the southern hemisphere
February 26, 2015
Brightness temperature in the southern hemisphere
February 19, 2015
Brightness temperature in the southern hemisphere
February 12, 2015
Brightness temperature in the southern hemisphere
February 5, 2015
Brightness temperature in the southern hemisphere
January 29, 2015
Brightness temperature in the southern hemisphere
January 22, 2015
Brightness temperature in the southern hemisphere
January 15, 2015
Brightness temperature in the southern hemisphere
January 8, 2015
Brightness temperature in the southern hemisphere
January 1, 2015
Publications
Brucker, L., Dinnat, E.P., and Koenig, L.S. (2014a). Weekly Gridded Aquarius L-band Radiometer/Scatterometer Observations and Salinity Retrievals Over the Polar Regions - Part 1: Product Description, The Cryosphere, 8, 905-913, doi:10.5194/tc-8-905-2014.
Brucker, L., Dinnat, E.P., and Koenig, L.S. (2014b). Weekly Gridded Aquarius L-band Radiometer/Scatterometer Observations and Salinity Retrievals Over the Polar Regions - Part 2: Initial Product Analysis, The Cryosphere, 8, 915-930, doi:10.5194/tc-8-915-2014.
Brucker, L., Dinnat, E.P., Picard, G., and Champollion, N. (2014c). Effect of Snow Surface Metamorphism on Aquarius L-Band Radiometer Observations at Dome C, Antarctica, IEEE Transactions on Geoscience and Remote Sensing, 52 (11), 1-10, doi: 10.1109/TGRS.2014.2312102.