SMAP Maps: Sea Surface Salinity (Northern Hemisphere)

NASA's Soil Moisture Active Passive (SMAP) mission began collecting sea surface salinity data in April 2015, overlapping with Aquarius observations for approximately three months. Using the same frequency as Aquarius (L-band; 1.41 GHz), SMAP's global salinity measurements continue the time series that began with Aquarius in August 2011.

The maps in this slideshow are generated from Version 4.0 (V4) of the SMAP sea surface salinity Level-3 (mapped) data. These monthly averaged data are gridded at 25 x 25 km (15.5 X 15.5 mi) resolution, with an approximate spatial resolution of 70km. They show a range of salinities from 33 to 38 using the Practical Salinity Scale (PSS; Lewis, 1980), which is roughly equivalent to parts per thousand. PSS and PSU (Practical Salinity Units, which is also used), are different names for the same thing.

Dark blues and purples represent lower salinities while reds show areas of higher sea surface salinity.

Click here to view a slideshow of sea surface salinity in the southern hemisphere.

  • Sea surface salinity, April 2015

    April 2015

  • Sea surface salinity, May 2015

    May 2015

  • Sea surface salinity, June 2015

    June 2015

  • Sea surface salinity, July 2015

    July 2015

  • Sea surface salinity, August 2015

    August 2015

  • Sea surface salinity, September 2015

    September 2015

  • Sea surface salinity, October 2015

    October 2015

  • Sea surface salinity, November 2015

    November 2015

  • Sea surface salinity, December 2015

    December 2015

  • Sea surface salinity, January 2016

    January 2016

  • Sea surface salinity, February 2016

    February 2016

  • Sea surface salinity, March 2016

    March 2016

  • Sea surface salinity, April 2016

    April 2016

  • Sea surface salinity, May 2016

    May 2016

  • Sea surface salinity, June 2016

    June 2016

  • Sea surface salinity, July 2016

    July 2016

  • Sea surface salinity, August 2016

    August 2016

  • Sea surface salinity, September 2016

    September 2016

  • Sea surface salinity, October 2016

    October 2016

  • Sea surface salinity, November 2016

    November 2016

  • Sea surface salinity, December 2016

    December 2016

  • Sea surface salinity, January 2017

    January 2017

  • Sea surface salinity, February 2017

    February 2017

  • Sea surface salinity, March 2017

    March 2017

  • Sea surface salinity, April 2017

    April 2017

  • Sea surface salinity, May 2017

    May 2017

  • Sea surface salinity, June 2017

    June 2017

  • Sea surface salinity, July 2017

    July 2017

  • Sea surface salinity, August 2017

    August 2017

  • Sea surface salinity, September 2017

    September 2017

  • Sea surface salinity, October 2017

    October 2017

  • Sea surface salinity, November 2017

    November 2017

  • Sea surface salinity, December 2017

    December 2017

  • Sea surface salinity, January 2018

    January 2018

  • Sea surface salinity, February 2018

    February 2018

  • Sea surface salinity, March 2018

    March 2018

  • Sea surface salinity, April 2018

    April 2018

  • Sea surface salinity, May 2018

    May 2018

  • Sea surface salinity, June 2018

    June 2018

  • Sea surface salinity, July 2018

    July 2018

  • Sea surface salinity, August 2018

    August 2018

  • Sea surface salinity, September 2018

    September 2018

  • Sea surface salinity, October 2018

    October 2018

  • Sea surface salinity, November 2018

    November 2018

  • Sea surface salinity, December 2018

    December 2018

  • Sea surface salinity, January 2019

    January 2019

  • Sea surface salinity, February 2019

    February 2019

  • Sea surface salinity, March 2019

    March 2019

  • Sea surface salinity, April 2019

    April 2019

  • Sea surface salinity, May 2019

    May 2019

  • Sea surface salinity, June 2019

    June 2019

  • Sea surface salinity, July 2019

    July 2019

  • Sea surface salinity, August 2019

    August 2019

  • Sea surface salinity, September 2019

    September 2019

  • Sea surface salinity, October 2019

    October 2019

  • Sea surface salinity, November 2019

    November 2019

  • Sea surface salinity, December 2019

    December 2019

  • Sea surface salinity, January 2020

    January 2020

  • Sea surface salinity, February 2020

    February 2020

  • Sea surface salinity, March 2020

    March 2020

  • Sea surface salinity, April 2020

    April 2020

  • Sea surface salinity, May 2020

    May 2020

  • Sea surface salinity, June 2020

    June 2020

  • Sea surface salinity, July 2020

    July 2020

  • Sea surface salinity, August 2020

    August 2020

  • Sea surface salinity, September 2020

    September 2020

  • Sea surface salinity, October 2020

    October 2020

  • Sea surface salinity, November 2020

    November 2020

  • Sea surface salinity, December 2020

    December 2020

  • Sea surface salinity, January 2021

    January 2021

  • Sea surface salinity, February 2021

    February 2021

  • Sea surface salinity, March 2021

    March 2021

  • Sea surface salinity, April 2021

    April 2021

  • Sea surface salinity, May 2021

    May 2021

  • Sea surface salinity, June 2021

    June 2021

  • Credit
  • Credit
Slideshow: Monthly composite maps of sea surface salinity (tap or hover over images to pause the slideshow; on mobile, swipe to restart).