Sea Surface Salinity Evaluation#

Overview#

This recipe compares the regional means of sea surface salinity with a reference dataset (ESACCI-SEA-SURFACE-SALINITY v1 or v2 by default). To do this, the recipe generates plots for the timeseries of each region and a radar plot showing (i) the mean state bias, and (ii) the ratio between the simulated and observed standard deviations of different regional averages of sea surface salinity, calculated in the temporal window for which observations and simulations overlap.

Preprocessor requirements:#

The recipe is created in a way that should make possible (although is not tested) to use it for other variables and datasets, even for more than one at a time. The diagnostic only expects variables with dimensions time and depth_id and it does not assume any other constraint.

It is therefore mandatory to keep the extract_shape preprocessor for more than one region and any form of region operation (mean, max, min …) to collapse the latitude and longitude coordinates. In case you want to try with variables that have extra dimensions (i.e. depth) you must add an extra preprocessor call to collapse them (i.e. depth_integration)

The recipe can be used with any shapefile. As it is, it uses the IHO Sea Areas (version 3) downloaded from https://marineregions.org/downloads.php, but any shapefile containing marine regions can be used.

Any number of regions can be choosed also, even though plots may look odd if too few or too many are selected.

Regions available on IHO Sea Areas file:#

  • Adriatic Sea

  • Aegean Sea

  • Alboran Sea

  • Andaman or Burma Sea

  • Arabian Sea

  • Arafura Sea

  • Arctic Ocean

  • Baffin Bay

  • Balearic (Iberian Sea)

  • Bali Sea

  • Baltic Sea

  • Banda Sea

  • Barentsz Sea

  • Bass Strait

  • Bay of Bengal

  • Bay of Biscay

  • Bay of Fundy

  • Beaufort Sea

  • Bering Sea

  • Bismarck Sea

  • Black Sea

  • Bristol Channel

  • Caribbean Sea

  • Celebes Sea

  • Celtic Sea

  • Ceram Sea

  • Chukchi Sea

  • Coral Sea

  • Davis Strait

  • East Siberian Sea

  • Eastern China Sea

  • English Channel

  • Flores Sea

  • Great Australian Bight

  • Greenland Sea

  • Gulf of Aden

  • Gulf of Alaska

  • Gulf of Aqaba

  • Gulf of Boni

  • Gulf of Bothnia

  • Gulf of California

  • Gulf of Finland

  • Gulf of Guinea

  • Gulf of Mexico

  • Gulf of Oman

  • Gulf of Riga

  • Gulf of St. Lawrence

  • Gulf of Suez

  • Gulf of Thailand

  • Gulf of Tomini

  • Halmahera Sea

  • Hudson Bay

  • Hudson Strait

  • Indian Ocean

  • Inner Seas off the West Coast of Scotland

  • Ionian Sea

  • Irish Sea and St. George’s Channel

  • Japan Sea

  • Java Sea

  • Kara Sea

  • Kattegat

  • Labrador Sea

  • Laccadive Sea

  • Laptev Sea

  • Ligurian Sea

  • Lincoln Sea

  • Makassar Strait

  • Malacca Strait

  • Mediterranean Sea - Eastern Basin

  • Mediterranean Sea - Western Basin

  • Molukka Sea

  • Mozambique Channel

  • North Atlantic Ocean

  • North Pacific Ocean

  • North Sea

  • Norwegian Sea

  • Persian Gulf

  • Philippine Sea

  • Red Sea

  • Rio de La Plata

  • Savu Sea

  • Sea of Azov

  • Sea of Marmara

  • Sea of Okhotsk

  • Seto Naikai or Inland Sea

  • Singapore Strait

  • Skagerrak

  • Solomon Sea

  • South Atlantic Ocean

  • South China Sea

  • South Pacific Ocean

  • Southern Ocean

  • Strait of Gibraltar

  • Sulu Sea

  • Tasman Sea

  • The Coastal Waters of Southeast Alaska and British Columbia

  • The Northwestern Passages

  • Timor Sea

  • Tyrrhenian Sea

  • White Sea

  • Yellow Sea

Available recipes and diagnostics#

Recipes are stored in recipes/

  • recipe_sea_surface_salinity.yml

Diagnostics are stored in diag_scripts/sea_surface_salinity/

  • compare_salinity.py: plot timeseries for each region and generate radar plot.

User settings in recipe#

  1. compare_salinity.py

    Required settings for script

    none

    Optional settings for script

    none

    Required settings for variables

    • ref_model: name of reference data set

    Optional settings for variables

    none

Variables#

  • sos (ocean, monthly, time latitude longitude)

Observations and reformat scripts#

  • ESACCI-SEA-SURFACE-SALINITY (sos)

References#

  • Diagnostic: please contact authors

  • ESACCI-SEA-SURFACE-SALINITY dataset: Boutin, J., J.-L. Vergely, J. Koehler, F. Rouffi, N. Reul: ESA Sea Surface Salinity Climate Change Initiative (Sea_Surface_Salinity_cci): Version 1.8 data collection. Centre for Environmental Data Analysis, 25 November 2019. doi: 10.5285/9ef0ebf847564c2eabe62cac4899ec41. http://dx.doi.org/10.5285/9ef0ebf847564c2eabe62cac4899ec41

Example plots#

../_images/radar_bias.png

Fig. 212 Radar plot showing the mean state biases (simulation minus observations) for the regional averages of sea surface salinity in the selected ocean basins and seas.#

../_images/radar_std.png

Fig. 213 Radar plot showing the ratio between the simulated and observed standard deviations of the regional averages of sea surface salinity in the selected ocean basins and seas.#