This dataset contains environmental layers used to model the predicted distribution of demersal fish bioregions for the paper: Hill et al. (2020) Determining Marine Bioregions: A comparison of quantitative approaches, Methods in Ecology and Evolution. It contains climatological variables from satellite and modelled data that represent sea floor and sea surface conditions likely to affect the distribution of demersal fish including: depth, slope, seafloor temperatures, seafloor current, seafloor nitrate, sea surface temperature, chlorophyll-a standard deviation and sea surface height standard deviation. Layers are presented at 0.1 degree resolution. "prediction_space" is a Rda file for R that consists of two objects: env_raster: a raster stack of the environmental layers pred_sp: a data.frame version of the env_raster where some variables have been transformed for statistical analysis and bioregion prediction. "Env_data_sources.xlsx" contains a description of each environmental variable and it's source.

This dataset is a collection of marine environmental data layers suitable for use in Southern Ocean species distribution modelling. All environmental layers have been generated at a spatial resolution of 0.1 degrees, covering the Southern Ocean extent (80 degrees S - 45 degrees S, -180 - 180 degrees). The layers include information relating to bathymetry, sea ice, ocean currents, primary production, particulate organic carbon, and other oceanographic data. An example of reading and using these data layers in R can be found at https://australianantarcticdivision.github.io/blueant/articles/SO_SDM_data.html. The following layers are provided: 1. Layer name: depth Description: Bathymetry. Downloaded from GEBCO 2014 (0.0083 degrees = 30sec arcmin resolution) and set at resolution 0.1 degrees. Then completed with the bathymetry layer manually corrected and provided in Fabri-Ruiz et al. (2017) Value range: -8038.722 - 0 Units: m Source: This study. Derived from GEBCO URL: https://www.gebco.net/data_and_products/gridded_bathymetry_data/ Citation: Fabri-Ruiz S, Saucede T, Danis B and David B (2017). Southern Ocean Echinoids database_An updated version of Antarctic, Sub-Antarctic and cold temperate echinoid database. ZooKeys, (697), 1. 2. Layer name: geomorphology Description: Last update on biodiversity.aq portal. Derived from O'Brien et al. (2009) seafloor geomorphic feature dataset. Mapping based on GEBCO contours, ETOPO2, seismic lines). 27 categories Value range: 27 categories Units: categorical Source: This study. Derived from Australian Antarctic Data Centre URL: https://data.aad.gov.au/metadata/records/Polar_Environmental_Data Citation: O'Brien, P.E., Post, A.L., and Romeyn, R. (2009) Antarctic-wide geomorphology as an aid to habitat mapping and locating vulnerable marine ecosystems. CCAMLR VME Workshop 2009. Document WS-VME-09/10 3. Layer name: sediments Description: Sediment features Value range: 14 categories Units: categorical Source: Griffiths 2014 (unpublished) URL: http://share.biodiversity.aq/GIS/antarctic/ 4. Layer name: slope Description: Seafloor slope derived from bathymetry with the terrain function of raster R package. Computation according to Horn (1981), ie option neighbor=8. The computation was done on the GEBCO bathymetry layer (0.0083 degrees resolution) and the resolution was then changed to 0.1 degrees. Unit set at degrees. Value range: 0.000252378 - 16.94809 Units: degrees Source: This study. Derived from GEBCO URL: https://www.gebco.net/data_and_products/gridded_bathymetry_data/ Citation: Horn, B.K.P., 1981. Hill shading and the reflectance map. Proceedings of the IEEE 69:14-47 5. Layer name: roughness Description: Seafloor roughness derived from bathymetry with the terrain function of raster R package. Roughness is the difference between the maximum and the minimum value of a cell and its 8 surrounding cells. The computation was done on the GEBCO bathymetry layer (0.0083 degrees resolution) and the resolution was then changed to 0.1 degrees. Value range: 0 - 5171.278 Units: unitless Source: This study. Derived from GEBCO URL: https://www.gebco.net/data_and_products/gridded_bathymetry_data/ 6. Layer name: mixed layer depth Description: Summer mixed layer depth climatology from ARGOS data. Regridded from 2-degree grid using nearest neighbour interpolation Value range: 13.79615 - 461.5424 Units: m Source: https://data.aad.gov.au/metadata/records/Polar_Environmental_Data 7. Layer name: seasurface_current_speed Description: Current speed near the surface (2.5m depth), derived from the CAISOM model (Galton-Fenzi et al. 2012, based on ROMS model) Value range: 1.50E-04 - 1.7 Units: m/s Source: This study. Derived from Australian Antarctic Data Centre URL: https://data.aad.gov.au/metadata/records/Polar_Environmental_Data Citation: see Galton-Fenzi BK, Hunter JR, Coleman R, Marsland SJ, Warner RC (2012) Modeling the basal melting and marine ice accretion of the Amery Ice Shelf. Journal of Geophysical Research: Oceans, 117, C09031. http://dx.doi.org/10.1029/2012jc008214, https://data.aad.gov.au/metadata/records/polar_environmental_data 8. Layer name: seafloor_current_speed Description: Current speed near the sea floor, derived from the CAISOM model (Galton-Fenzi et al. 2012, based on ROMS) Value range: 3.40E-04 - 0.53 Units: m/s Source: This study. Derived from Australian Antarctic Data Centre URL: https://data.aad.gov.au/metadata/records/Polar_Environmental_Data Citation: see Galton-Fenzi BK, Hunter JR, Coleman R, Marsland SJ, Warner RC (2012) Modeling the basal melting and marine ice accretion of the Amery Ice Shelf. Journal of Geophysical Research: Oceans, 117, C09031. http://dx.doi.org/10.1029/2012jc008214, https://data.aad.gov.au/metadata/records/polar_environmental_data 9. Layer name: distance_antarctica Description: Distance to the nearest part of the Antarctic continent Value range: 0 - 3445 Units: km Source: https://data.aad.gov.au/metadata/records/Polar_Environmental_Data 10. Layer name: distance_canyon Description: Distance to the axis of the nearest canyon Value range: 0 - 3117 Units: km Source: https://data.aad.gov.au/metadata/records/Polar_Environmental_Data 11. Layer name: distance_max_ice_edge Description: Distance to the mean maximum winter sea ice extent (derived from daily estimates of sea ice concentration) Value range: -2614.008 - 2314.433 Units: km Source: https://data.aad.gov.au/metadata/records/Polar_Environmental_Data 12. Layer name: distance_shelf Description: Distance to nearest area of seafloor of depth 500m or shallower Value range: -1296 - 1750 Units: km Source: https://data.aad.gov.au/metadata/records/Polar_Environmental_Data 13. Layer name: ice_cover_max Description: Ice concentration fraction, maximum on [1957-2017] time period Value range: 0 - 1 Units: unitless Source: BioOracle accessed 24/04/2018, see Assis et al. (2018) URL: http://www.bio-oracle.org/ Citation: Assis J, Tyberghein L, Bosch S, Verbruggen H, Serrao EA and De Clerck O (2018). Bio_ORACLE v2. 0: Extending marine data layers for bioclimatic modelling. Global Ecology and Biogeography, 27(3), 277-284 , see also https://www.ecmwf.int/en/research/climate-reanalysis/ocean-reanalysis 14. Layer name: ice_cover_mean Description: Ice concentration fraction, mean on [1957-2017] time period Value range: 0 - 0.9708595 Units: unitless Source: BioOracle accessed 24/04/2018, see Assis et al. (2018) URL: http://www.bio-oracle.org/ Citation: Assis J, Tyberghein L, Bosch S, Verbruggen H, Serrao EA and De Clerck O (2018). Bio_ORACLE v2. 0: Extending marine data layers for bioclimatic modelling. Global Ecology and Biogeography, 27(3), 277-284 , see also https://www.ecmwf.int/en/research/climate-reanalysis/ocean-reanalysis 15. Layer name: ice_cover_min Description: Ice concentration fraction, minimum on [1957-2017] time period Value range: 0 - 0.8536261 Units: unitless Source: BioOracle accessed 24/04/2018, see Assis et al. (2018) URL: http://www.bio-oracle.org/ Citation: Assis J, Tyberghein L, Bosch S, Verbruggen H, Serrao EA and De Clerck O (2018). Bio_ORACLE v2. 0: Extending marine data layers for bioclimatic modelling. Global Ecology and Biogeography, 27(3), 277-284 , see also https://www.ecmwf.int/en/research/climate-reanalysis/ocean-reanalysis 16. Layer name: ice_cover_range Description: Ice concentration fraction, difference maximum-minimum on [1957-2017] time period Value range: 0 - 1 Units: unitless Source: BioOracle accessed 24/04/2018, see Assis et al. (2018) URL: http://www.bio-oracle.org/ Citation: Assis J, Tyberghein L, Bosch S, Verbruggen H, Serrao EA and De Clerck O (2018). Bio_ORACLE v2. 0: Extending marine data layers for bioclimatic modelling. Global Ecology and Biogeography, 27(3), 277-284 , see also https://www.ecmwf.int/en/research/climate-reanalysis/ocean-reanalysis 17. Layer name: ice_thickness_max Description: Ice thickness, maximum on [1957-2017] time period Value range: 0 - 3.471811 Units: m Source: BioOracle accessed 24/04/2018, see Assis et al. (2018) URL: http://www.bio-oracle.org/ Citation: Assis J, Tyberghein L, Bosch S, Verbruggen H, Serrao EA and De Clerck O (2018). Bio_ORACLE v2. 0: Extending marine data layers for bioclimatic modelling. Global Ecology and Biogeography, 27(3), 277-284 , see also https://www.ecmwf.int/en/research/climate-reanalysis/ocean-reanalysis 18. Layer name: ice_thickness_mean Description: Ice thickness, mean on [1957-2017] time period Value range: 0 - 1.614133 Units: m Source: BioOracle accessed 24/04/2018, see Assis et al. (2018) URL: http://www.bio-oracle.org/ Citation: Assis J, Tyberghein L, Bosch S, Verbruggen H, Serrao EA and De Clerck O (2018). Bio_ORACLE v2. 0: Extending marine data layers for bioclimatic modelling. Global Ecology and Biogeography, 27(3), 277-284 , see also https://www.ecmwf.int/en/research/climate-reanalysis/ocean-reanalysis 19. Layer name: ice_thickness_min Description: Ice thickness, minimum on [1957-2017] time period Value range: 0 - 0.7602701 Units: m Source: BioOracle accessed 24/04/2018, see Assis et al. (2018) URL: http://www.bio-oracle.org/ Citation: Assis J, Tyberghein L, Bosch S, Verbruggen H, Serrao EA and De Clerck O (2018). Bio_ORACLE v2. 0: Extending marine data layers for bioclimatic modelling. Global Ecology and Biogeography, 27(3), 277-284 , see also https://www.ecmwf.int/en/research/climate-reanalysis/ocean-reanalysis 20. Layer name: ice_thickness_range Description: Ice thickness, difference maximum-minimum on [1957-2017] time period Value range: 0 - 3.471811 Units: m Source: BioOracle accessed 24/04/2018, see Assis et al. (2018) URL: http://www.bio-oracle.org/ Citation: Assis J, Tyberghein L, Bosch S, Verbruggen H, Serrao EA and De Clerck O (2018). Bio_ORACLE v2. 0: Extending marine data layers for bioclimatic modelling. Global Ecology and Biogeography, 27(3), 277-284 , see also https://www.ecmwf.int/en/research/climate-reanalysis/ocean-reanalysis 21. Layer name: chla_ampli_alltime_2005_2012 Description: Chlorophyll-a concentrations obtained from MODIS satellite data. Amplitude of pixel values (difference between maximal and minimal value encountered by each pixel during all months of the period [2005-2012]) Value range: 0 - 77.15122 Units: mg/m^3 Source: https://oceandata.sci.gsfc.nasa.gov/MODIS-Aqua/Mapped/Monthly/9km/chlor_a/ URL: https://modis.gsfc.nasa.gov/data/dataprod/chlor_a.php 22. Layer name: chla_max_alltime_2005_2012 Description: Chlorophyll-a concentrations obtained from MODIS satellite data. Maximal value encountered by each pixel during all months of the period [2005-2012] Value range: 0 - 77.28562 Units: mg/m^3 Source: https://oceandata.sci.gsfc.nasa.gov/MODIS-Aqua/Mapped/Monthly/9km/chlor_a/ URL: https://modis.gsfc.nasa.gov/data/dataprod/chlor_a.php 23. Layer name: chla_mean_alltime_2005_2012 Description: Chlorophyll-a concentrations obtained from MODIS satellite data. Mean value of each pixel during all months of the period [2005-2012] Value range: 0 - 30.42691 Units: mg/m^3 Source: https://oceandata.sci.gsfc.nasa.gov/MODIS-Aqua/Mapped/Monthly/9km/chlor_a/ URL: https://modis.gsfc.nasa.gov/data/dataprod/chlor_a.php 24. Layer name: chla_min_alltime_2005_2012 Description: Chlorophyll-a concentrations obtained from MODIS satellite data. Minimal value encountered by each pixel during all months of the period [2005-2012] Value range: 0 - 29.02929 Units: mg/m^3 Source: https://oceandata.sci.gsfc.nasa.gov/MODIS-Aqua/Mapped/Monthly/9km/chlor_a/ URL: https://modis.gsfc.nasa.gov/data/dataprod/chlor_a.php 25. Layer name: chla_sd_alltime_2005_2012 Description: Chlorophyll-a concentrations obtained from MODIS satellite data. Standard deviation value of each pixel during all months of the period [2005-2012] Value range: 0 - 27.9877 Units: mg/m^3 Source: https://oceandata.sci.gsfc.nasa.gov/MODIS-Aqua/Mapped/Monthly/9km/chlor_a/ URL: https://modis.gsfc.nasa.gov/data/dataprod/chlor_a.php 26. Layer name: POC_2005_2012_ampli Description: Particulate organic carbon, model Lutz et al. (2007). Amplitude value (difference maximal and minimal value, see previous layers) all seasonal layers [2005-2012] Value range: 0 - 1.31761 Units: g/m^2/d Source: This study. Following Lutz et al. (2007) URL: https://data.aad.gov.au/metadata/records/Particulate_carbon_export_flux_layers Citation: Lutz MJ, Caldeira K, Dunbar RB and Behrenfeld MJ (2007). Seasonal rhythms of net primary production and particulate organic carbon flux to depth describe the efficiency of biological pump in the global ocean. Journal of Geophysical Research: Oceans, 112(C10). 27. Layer name: POC_2005_2012_max Description: Particulate organic carbon, model Lutz et al. (2007). Maximal value encountered on each pixel among all seasonal layers [2005-2012] Value range: 0.00332562 - 1.376601 Units: g/m^2/d Source: This study. Following Lutz et al. (2007) URL: https://data.aad.gov.au/metadata/records/Particulate_carbon_export_flux_layers Citation: Lutz MJ, Caldeira K, Dunbar RB and Behrenfeld MJ (2007). Seasonal rhythms of net primary production and particulate organic carbon flux to depth describe the efficiency of biological pump in the global ocean. Journal of Geophysical Research: Oceans, 112(C10). 28. Layer name: POC_2005_2012_mean Description: Particulate organic carbon, model Lutz et al. (2007). Mean all seasonal layers [2005-2012] Value range: 0.003184335 - 0.5031364 Units: g/m^2/d Source: This study. Following Lutz et al. (2007) URL: https://data.aad.gov.au/metadata/records/Particulate_carbon_export_flux_layers Citation: Lutz MJ, Caldeira K, Dunbar RB and Behrenfeld MJ (2007). Seasonal rhythms of net primary production and particulate organic carbon flux to depth describe the efficiency of biological pump in the global ocean. Journal of Geophysical Research: Oceans, 112(C10). 29. Layer name: POC_2005_2012_min Description: Particulate organic carbon, model Lutz et al. (2007). Minimal value encountered on each pixel among all seasonal layers [2005-2012] Value range: 0.003116508 - 0.1313119 Units: g/m^2/d Source: This study. Following Lutz et al. (2007) URL: https://data.aad.gov.au/metadata/records/Particulate_carbon_export_flux_layers Citation: Lutz MJ, Caldeira K, Dunbar RB and Behrenfeld MJ (2007). Seasonal rhythms of net primary production and particulate organic carbon flux to depth describe the efficiency of biological pump in the global ocean. Journal of Geophysical Research: Oceans, 112(C10). 30. Layer name: POC_2005_2012_sd Description: Particulate organic carbon, model Lutz et al. (2007). Standard deviation all seasonal layers [2005-2012] Value range: 3.85E-08 - 0.4417001 Units: g/m^2/d Source: This study. Following Lutz et al. (2007) URL: https://data.aad.gov.au/metadata/records/Particulate_carbon_export_flux_layers Citation: Lutz MJ, Caldeira K, Dunbar RB and Behrenfeld MJ (2007). Seasonal rhythms of net primary production and particulate organic carbon flux to depth describe the efficiency of biological pump in the global ocean. Journal of Geophysical Research: Oceans, 112(C10). 31. Layer name: seafloor_oxy_1955_2012_ampli Description: Amplitude (difference maximum-minimum) value encountered for each pixel on all month layers of seafloor oxygen concentration over [1955-2012], modified from WOCE Value range: 0.001755714 - 5.285187 Units: mL/L Source: Derived from World Ocean Circulation Experiment 2013 URL: https://www.nodc.noaa.gov/OC5/woa13/woa13data.html 32. Layer name: seafloor_oxy_1955_2012_max Description: Maximum value encountered for each pixel on all month layers of oxygen concentration over [1955-2012], modified from WOCE Value range: 3.059685 - 11.52433 Units: mL/L Source: Derived from World Ocean Circulation Experiment 2013 URL: https://www.nodc.noaa.gov/OC5/woa13/woa13data.html 33. Layer name: seafloor_oxy_1955_2012_mean Description: Mean seafloor oxygen concentration over [1955-2012] (average of all monthly layers), modified from WOCE Value range: 2.836582 - 8.858084 Units: mL/L Source: Derived from World Ocean Circulation Experiment 2013 URL: https://www.nodc.noaa.gov/OC5/woa13/woa13data.html 34. Layer name: seafloor_oxy_1955_2012_min Description: Minimum value encountered for each pixel on all month layers of seafloor oxygen concentration over [1955-2012], modified from WOCE Value range: 0.4315577 - 8.350794 Units: mL/L Source: Derived from World Ocean Circulation Experiment 2013 URL: https://www.nodc.noaa.gov/OC5/woa13/woa13data.html 35. Layer name: seafloor_oxy_1955_2012_sd Description: Standard deviation seafloor oxygen concentration over [1955-2012] (of all monthly layers), modified from WOCE Value range: 0.000427063 - 1.588707 Units: mL/L Source: Derived from World Ocean Circulation Experiment 2013 URL: https://www.nodc.noaa.gov/OC5/woa13/woa13data.html 36. Layer name: seafloor_sali_2005_2012_ampli Description: Amplitude (difference maximum-minimum) value encountered for each pixel on all month layers of seafloor salinity over [2005-2012], modified from WOCE Value range: 0.000801086 - 4.249901 Units: PSU Source: Derived from World Ocean Circulation Experiment 2013 URL: https://www.nodc.noaa.gov/OC5/woa13/woa13data.html 37. Layer name: seafloor_sali_2005_2012_max Description: Maximum value encountered for each pixel on all month layers of seafloor salinity over [2005-2012], modified from WOCE Value range: 32.90105 - 35.3997 Units: PSU Source: Derived from World Ocean Circulation Experiment 2013 URL: https://www.nodc.noaa.gov/OC5/woa13/woa13data.html 38. Layer name: seafloor_sali_2005_2012_mean Description: Mean seafloor salinity over [2005-2012] (average of all monthly layers), modified from WOCE Value range: 32.51107 - 35.03207 Units: PSU Source: Derived from World Ocean Circulation Experiment 2013 URL: https://www.nodc.noaa.gov/OC5/woa13/woa13data.html 39. Layer name: seafloor_sali_2005_2012_min Description: Minimum value encountered for each pixel on all month layers of seafloor salinity over [2005-2012], modified from WOCE Value range: 29.8904 - 34.97735 Units: PSU Source: Derived from World Ocean Circulation Experiment 2013 URL: https://www.nodc.noaa.gov/OC5/woa13/woa13data.html 40. Layer name: seafloor_sali_2005_2012_sd Description: Standard deviation seafloor salinity over [2005-2012] (of all monthly layers), modified from WOCE Value range: 0.000251834 - 1.36245 Units: PSU Source: Derived from World Ocean Circulation Experiment 2013 URL: https://www.nodc.noaa.gov/OC5/woa13/woa13data.html 41. Layer name: seafloor_temp_2005_2012_ampli Description: Amplitude (difference maximum-minimum) value encountered for each pixel on all month layers of seafloor temperature over [2005-2012], modified from WOCE Value range: 0.0086 - 8.625669 Units: degrees C Source: Derived from World Ocean Circulation Experiment 2013 URL: https://www.nodc.noaa.gov/OC5/woa13/woa13data.html 42. Layer name: seafloor_temp_2005_2012_max Description: Maximum value encountered for each pixel on all month layers of seafloor temperature over [2005-2012], modified from WOCE Value range: -2.021455 - 15.93171 Units: degrees C Source: Derived from World Ocean Circulation Experiment 2013 URL: https://www.nodc.noaa.gov/OC5/woa13/woa13data.html 43. Layer name: seafloor_temp_2005_2012_mean Description: Mean seafloor temperature over [2005-2012] (average of all monthly layers), modified from WOCE Value range: -2.085796 - 13.23161 Units: degrees C Source: Derived from World Ocean Circulation Experiment 2013 URL: https://www.nodc.noaa.gov/OC5/woa13/woa13data.html 44. Layer name: seafloor_temp_2005_2012_min Description: Minimum value encountered for each pixel on all month layers of seafloor temperature over [2005-2012], modified from WOCE Value range: -2.1 - 11.6431 Units: degrees C Source: Derived from World Ocean Circulation Experiment 2013 URL: https://www.nodc.noaa.gov/OC5/woa13/woa13data.html 45. Layer name: seafloor_temp_2005_2012_sd Description: Standard deviation seafloor temperature over [2005-2012] (of all monthly layers), modified from WOCE Value range: 0.002843571 - 2.877084 Units: degrees C Source: Derived from World Ocean Circulation Experiment 2013 URL: https://www.nodc.noaa.gov/OC5/woa13/woa13data.html 46. Layer name: extreme_event_max_chl_2005_2012_ampli Description: Amplitude (difference maximum-minimum) number of the number of extreme events calculated between 2005 and 2012 Value range: integer values 0 - 3 Units: unitless Source: derived from chlorophyll-a concentration layers 47. Layer name: extreme_event_max_chl_2005_2012_max Description: Maximum number of extreme events calculated between 2005 and 2012 Value range: integer values 0 - 5 Units: unitless Source: derived from chlorophyll-a concentration layers 48. Layer name: extreme_event_max_chl_2005_2012_mean Description: Mean of the number of extreme events calculated between 2005 and 2012 Value range: 0 - 3.875 Units: unitless Source: derived from chlorophyll-a concentration layers 49. Layer name: extreme_event_max_chl_2005_2012_min Description: Minimum number of extreme events calculated between 2005 and 2012 Value range: integer values 0 - 5 Units: unitless Source: derived from chlorophyll-a concentration layers 50. Layer name: extreme_event_min_chl_2005_2012_ampli Description: Amplitude (difference maximum-minimum) number of the number of extreme events calculated between 2005 and 2012 Value range: integer values 0 - 9 Units: unitless Source: derived from chlorophyll-a concentration layers 51. Layer name: extreme_event_min_chl_2005_2012_max Description: Maximum number of extreme events calculated between 2005 and 2012 Value range: integer values 0 - 11 Units: unitless Source: derived from chlorophyll-a concentration layers 52. Layer name: extreme_event_min_chl_2005_2012_mean Description: Mean of the number of extreme events calculated between 2005 and 2012 Value range: 0 - 11 Units: unitless Source: derived from chlorophyll-a concentration layers 53. Layer name: extreme_event_min_chl_2005_2012_min Description: Minimum number of extreme events calculated between 2005 and 2012 Value range: integer values 0 - 11 Units: unitless Source: derived from chlorophyll-a concentration layers 54. Layer name: extreme_event_min_oxy_1955_2012_nb Description: Number of extreme events (minimal seafloor oxygen concentration records) that happened between January and December of the year Value range: integer values 0 - 12 Units: per year Source: derived from seafloor oxygen concentration layers 55. Layer name: extreme_event_max_sali_2005_2012_nb Description: Number of extreme events (maximal seafloor salinity records) that happened between January and December of the year Value range: integer values 0 - 12 Units: per year Source: derived from seafloor salinity layers 56. Layer name: extreme_event_min_sali_2005_2012_nb Description: Number of extreme events (minimal seafloor salinity records) that happened between January and December of the year Value range: integer values 0 - 12 Units: per year Source: derived from seafloor salinity layers 57. Layer name: extreme_event_max_temp_2005_2012_nb Description: Number of extreme events (maximal seafloor temperature records) that happened between January and December of the year Value range: integer values 0 - 12 Units: per year Source: derived from seafloor temperature layers 58. Layer name: extreme_event_min_temp_2005_2012_nb Description: Number of extreme events (minimal seafloor temperature records) that happened between January and December of the year Value range: integer values 0 - 12 Units: per year Source: derived from seafloor temperature layers