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Greenland, Iceland and Norwegian Seas Regional Climatology

The Greenland, Iceland, and Norwegian Seas (GINS) are gateways for water exchange between the North Atlantic Ocean and the Arctic that play a key role in the global climate system. The presence of oil, fisheries, and other natural and material resources have spurred intensive observation and research in the region. Version 2 features significant upgrades to individual decadal fields.

Greenland, Iceland, and Norwegian Seas

These decadal climatologies were generated from GINS regional data in the World Ocean Database (WOD) collected from 1955 to 2012. The source datasets are described in WOD 2013.



Data   |   Figures


Data   |   Figures

Seidov, Dan; Baranova, Olga K.; Biddle, Mathew; Boyer, Timothy P.; Johnson, Daphne R.; Mishonov, Alexey V.; Paver, Christopher; Zweng, Melissa (2013). Greenland-Iceland-Norwegian Seas Regional Climatology (NCEI Accession 0112824). [indicate subset used]. NOAA National Centers for Environmental Information. Dataset. doi:10.7289/V5GT5K30.

Seidov, D., O.K. Baranova, T.P. Boyer, S.L. Cross, A.V. Mishonov, A.R. Parsons, J.R. Reagan, and K.W. Weathers (2018), Greenland-Iceland-Norwegian Seas Regional Climatology version 2, Regional Climatology Team, NOAA/NCEI.


The GINS RC v2 is a set of six decadal mean fields for temperature and salinity within the 50°N to 85°N and 45°W to 15°E domain comprising the Greenland, Iceland, and Norwegian Seas and adjacent areas of the northern North Atlantic and Arctic Oceans.

The six decadal climatologies of temperature and salinity use all data available in WOD13 from 1955 to 2012. There are five 10-year (1955-1964, 1965-1974, 1975-1984, 1985-1994, and 1995-2004) climatologies and an 8-year (2005-2012) climatology that were calculated for annual, seasonal, and monthly time periods. Seasons are as follows: Winter (January-March), Spring (April-June), Summer (July-September), and Fall (October-December). Additionally, there is a 58-year climatology defined as "all averaged decades," which was computed by averaging all six decadal climatologies and represents the long-term mean state of the ocean in the GINS region.


Decadal climatologies included in the GINS RC v2 are comprised of objectively analyzed temperature and salinity fields, and additional parameters including:

  • Simple statistical means
  • Data distributions
  • Standard deviations
  • Standard errors of the mean
  • Observed minus analyzed
  • Seasonal minus annual distributions for both temperature and salinity

This is the first quality-controlled regional climatology of the GINS region with 1/10°x1/10° spatial resolution and seasonal temporal resolution for both temperature and salinity for six consecutive decades.

Analysis Methods

Seasonal and annual fields are based on complete monthly analyses of all three horizontal grids (1°x1°, a 1/4°x1/4°, and 1/10°x1/10°), which are computed by averaging six decadal monthly analyses from 1955 to 2012. Seasonal fields at all depths above 1500 meters are computed from the average of the three months comprising each season (e.g., January, February and March for winter), while annual mean fields are computed by averaging the four seasonal fields at all depths. The annual analysis of measurements below 1500 meters is the mean of the four seasonal analyses, and only shows annual and seasonal fields (the monthly fields are not shown). Annual, seasonal, and monthly fields for the six individual decades are presented on 1°x1° and 1/4°x1/4° grids, with the annual and seasonal fields also available on a 1/10°x1/10° grid. For the aggregated ocean climate state between 1955 and 2012 (i.e., the 'all averaged decades'), annual, seasonal and monthly fields are shown for all three resolutions.

Product Overlap

The Climatological Atlas of the Nordic Seas and Northern North Atlantic (Korablev et al., 2014) overlaps significantly with the GIN Seas domain. Both regional climatologies have annual and monthly decadal temperature and salinity fields with 1/4°x1/4° resolution built using WOD13. However, each product was built using different methodologies, and cover substantially different dates, making them complementary rather than overlapping. Additionally, the GINS RC v2 includes annual, seasonal and monthly temperature and salinity fields compiled on 1°x1° and annual and seasonal fields on the 1/10°x1/10° grid, while the Climatological Atlas of the Nordic Seas and Northern North Atlantic provides oxygen and density fields on 1/4°x1/4° grid. Updates to GINS RC v2 allow both products to function side-by-side in a wide range of applications, creating a more comprehensive understanding of ocean variability in the GINS and adjacent regions.

Using High Resolution Fields

When available, higher spatial resolution grids provide major advantages over courser grids (Seidov et al., 2016). They reveal more outliers and, more importantly, enable more well sustained gridded field structures because of the significantly shorter radius of influence in the objective analysis procedure, especially in regions with sharp gradients of the essential oceanographic parameter (e.g. temperature, salinity, etc.).

In the GINS subpolar latitudes, mesoscale elements of hydrographic fields are easier to see on maps with 1/10°x1/10° resolution. They are better preserved in the generated climatological fields, which makes high-resolution climatologies more valuable for ocean modeling and for ocean climate change analysis (Seidov et al., 2017).

It is important to note that the high-resolution monthly temperature and salinity data coverage on the 1/10°x1/10° grid has more gaps than seasonal and annual timespans. In general, all high-resolution analyzed fields should be reviewed carefully before use in critical mission applications. Users are advised to review the data distribution and statistical mean arrays before deciding whether to use the high-resolution analyzed temperature and salinity fields or their climatological means. Moreover, the monthly maps of objectively analyzed data on 1/10°x1/10° may show irregularities which are too strong in some regions with fewer profiles (more data gaps) and are, in our view, artefacts caused by interpolation and plotting. While such cases are uncommon, careful review of fields with such occurrences is recommended.


45°W to 15°E longitudes and from 50°N to 84.5°N latitudes

Temporal Resolution

All data from the WOD13 for the GINS domain were used to calculate six decadal climatologies within the following time periods: 1955-1964; 1965-1974; 1975-1984; 1985-1994; 1995-2004; 2005-2012. The all averaged climatology was calculated by averaging the six individual decades listed above (see World Ocean Database 2013 Introduction).

Each decadal climatology consists of:

Annual Fields
Computed as 12-month averages
Seasonal Fields
Winter (Jan.-Mar.), Spring (Apr.-Jun.), Summer (Jul.-Sep.), Fall (Oct.-Dec.) computed as 3-month averages
Monthly Fields

Spatial Resolution

Annual and Seasonal Fields
1°x1°, 1/4°x1/4°, and 1/10°x1/10° geographic grids
Monthly Fields
1°x1° and 1/4°x1/4° grids for all decades; on the 1/10°x1/10° grid, monthly fields are available for the averaged decades only

Vertical Resolution

Annual and Seasonal Fields
Calculated from 0 to 4000 m depth on 87 standard levels (from the sea surface to the maximum depth in the GINs part of the domain)
Monthly Fields
0 to 1500 m on 57 standard levels

Standard depth levels in the GINS regional climatology are the same as in the WOA13 (see Table 3 in the WOA13 documentation).

Additional Fields

  • Simple statistical means
  • Data distributions
  • Standard deviations
  • Standard errors of the mean
  • Observed minus analyzed
  • Seasonal minus annual distributions for both temperature and salinity.


Temperature Units
Unitless on the Practical Salinity Scale-1978 [PSS]


For all three grid resolutions, mean depth values at the center of a grid square under its respective resolution were extracted from the ETOPO2 World Ocean bathymetry.


The methods of calculating mean climatological fields are described in details in the following publications: Temperature: Locarnini et al., 2013, Salinity: Zweng et al., 2013. Additional details regarding high-resolution climatological calculations can be found in Boyer et al., 2005. Radii of influence for the objective analysis procedure, including the 1/10° grid resolution. Table has been updated from (Boyer et al., 2005).

Pass1° radius of influence1/4° radius of influence1/10° radius of influence
1892 km321 km253 km
2669 km267 km198 km
3446 km214 km154 km

Most of the procedures used for generating NCEI regional climatologies are similar to those used for WOA18, e.g., (Locarnini et al., 2018; Zweng et al., 2018). Several recently published studies of long-term ocean climate change are based on SWNARC (Seidov et al., 2015; Seidov et al., 2017; Seidov et al., 2018).

Related Publications

Boyer, T., S. Levitus, H. Garcia, R.A. Locarnini, C. Stephens, J. Antonov, 2005: Objective analyses of annual, seasonal, and monthly temperature and salinity for the world ocean on a 0.25 degree grid. International Journal of Climatology, 25(7), 931-945.

Boyer, T.P., J.I. Antonov, O.K. Baranova, C. Coleman, H.E. Garcia, A. Grodsky, D.R. Johnson, R.A. Locarnini, A.V. Mishonov, T.D. O'Brien, C.R. Paver, J.R. Reagan, D. Seidov, I.V. Smolyar, M.M. Zweng, 2013: World Ocean Database 2013. Sydney Levitus, Ed.; Alexey Mishonov, Technical Ed.; NOAA Atlas NESDIS 72, 209 pp. doi:10.7289/V5NZ85MT.

Korablev, A., A. Smirnov, and O. K. Baranova, 2014. Climatological Atlas of the Nordic Seas and Northern North Atlantic. D. Seidov, A. R. Parsons, Eds., NOAA Atlas NESDIS 77, 122 pp., dataset doi:10.7289/V54B2Z78, publication doi:10.7289/V5K64G16.

Levitus, S., 1982: Climatological Atlas of the World Ocean. NOAA Professional Paper 13, 173 pp., U.S. Gov. Printing Office, Rockville, MD.

Locarnini, R.A., A.V. Mishonov, J.I. Antonov, T.P. Boyer, H.E. Garcia, O.K. Baranova, M.M. Zweng, C.R. Paver, J.R. Reagan, D.R. Johnson, M. Hamilton, and D. Seidov, 2013: World Ocean Atlas 2013, Volume 1: Temperature. S. Levitus, Ed., A. Mishonov Technical Ed.; NOAA Atlas NESDIS 73, 40 pp. doi:10.7289/V55X26VD.

Seidov, D., O.K. Baranova, T. Boyer, S.L. Cross, A.V. Mishonov, A.R. Parsons, 2016: Northwest Atlantic Regional Ocean Climatology. NOAA Atlas NESDIS 80, Tech. Ed.: A.V. Mishonov. Silver Spring, MD, 56 pp. doi:10.7289/V5/ATLAS-NESDIS-80.

Seidov, D., A. Mishonov, J. Reagan, and R. Parsons, 2017: Multidecadal variability and climate shift in the North Atlantic Ocean, Geophys. Res. Let., 44(10), 4985-4993, doi:10.1002/2017GL073644.

Zweng, M.M, J.R. Reagan, J.I. Antonov, R.A. Locarnini, A.V. Mishonov, T.P. Boyer, H.E. Garcia, O.K. Baranova, D.R. Johnson, D.Seidov, M.M. Biddle, 2013: World Ocean Atlas 2013, Volume 2: Salinity. S. Levitus, Ed., A. Mishonov, Technical Ed.; NOAA Atlas NESDIS 74, 39 pp. doi:10.7289/V5251G4D.