A set of mean fields for temperature and salinity for the Arctic Seas and environs are available for viewing and downloading. Area: The area encompassed is all longitudes from 60°N to 90°N latitudes. Horizontal resolution: Temperature and salinity are available on a 1°x1° and a 1/4°x1/4° latitude/longitude grid. Time resolution: All climatologies for all variables use all available data regardless of year of measurement. Climatologies were calculated for annual (all-data), seasonal, and monthly time periods. Seasons are as follows: Winter (Jan.-Mar.), Spring (Apr.-Jun.), Summer (Jul.-Aug.), Fall (Oct.-Dec.). Vertical resolution: Temperature and salinity are available on 87 standard levels with higher vertical resolution than the World Ocean Atlas 2009 (WOA09), but levels extend from the surface to 4000 m. Units: Temperature units are °C. Salinity is unitless on the Practical Salinity Scale-1978 [PSS]. Data used: All data from the area found in the World Ocean Database (WOD) as of the end of 2011. For a description of this dataset, please see World Ocean Database 2009 IntroductionMethod: The method followed for calculation of the mean climatological fields is detailed in the following publications: Temperature: Locarnini et al., 2010, Salinity: Antonov et al., 2010. Additional details on the 1/4° climatological calculation are found in Boyer et al., 2005, from: <a href="http://www.nodc.noaa.gov/OC5/regional_climate/arctic/" target="_blank">NOAA</a> Reference: Boyer, T.P., O.K. Baranova, M. Biddle, D.R. Johnson, A.V. Mishonov, C. Paver, D. Seidov and M. Zweng (2012), Arctic Regional Climatology, Regional Climatology Team, NOAA/NODC, source: <a href="www.nodc.noaa.gov/OC5/regional_climate/arctic" target="_blank">NOAA</a>

There is a great variation and heterogeneity among terrestrial Arctic ecosystems. This is further described as biogeographical areas in the Annotated Checklist of the Pan-Arctic Flora (Elven et al. 2020), as vegetation zones (Walker et al. 2005, Raynolds et al 2019) or as ecoregions recognised by Terrestrial Ecoregions of the World (Olson et al. 2001). The START focuses on high and low Arctic regions consistent with the CAVM’s subzones A to E, as shown in Figure 1-2 and Figure 2-1 STATE OF THE ARCTIC TERRESTRIAL BIODIVERSITY REPORT - Chapter 2 - Page 19 - Figure 2.1

Biogeographic borders in the Barents Sea based on species distributions of bryozoans. Average position of the border with 50:50% of Atlantic boreal and Arctic species numbers is indicated by the pink line, and the red and green lines indicate the extreme positions of the border in cold and warm periods respectively. Area III between them is the transitional zone between the Atlantic boreal and the Arctic regions. Thus, area I always has > 50% Atlantic boreal species, and area II always > 50% Arctic species (after Denisenko 1990).

Arthropods (e.g., shrimps, crabs, sea spiders, amphipods, isopods) dominate taxon numbers in all Arctic regions, followed by polychaetes (e.g., bristle worms) and mollusks (e.g., gastropods, bivalves). Other taxon groups are diverse in some regions, such as bryozoans in the Kara Sea, cnidarians in the Atlantic Arctic, and foraminiferans in the Arctic deep-sea basins. This pattern is biased, however, by the meiofauna inclusion for the Arctic Basin (macro- and meiofauna size ranges overlap substantially in deep-sea fauna, so nematodes and foraminiferans are included) and the influence of a lack of specialists for some difficult taxonomic groups. STATE OF THE ARCTIC MARINE BIODIVERSITY REPORT - <a href="https://arcticbiodiversity.is/findings/benthos" target="_blank">Chapter 3</a> - Page 89 - Box figure 3.3.1 Each region of the Pan Arctic has been sampled with a set of different sampling gears, including grab, sledge and trawl, while other areas has only been sampled with grab. Here is the complete species/taxa number and the % distribution of species/taxa in main phyla, per region of the Pan Arctic.

Figure 3-1 Long-term trends in ice duration (as days) in the River Torne (upper plot) and Lake Torneträsk (lower plot) at 68° north on the Scandinavian peninsula. Lines show smooth fit. Data source: Swedish Meteorological and Hydrological Institute. State of the Arctic Freshwater Biodiversity Report - Chapter 3 - Page 19 - Figure 3-1

Figure 4 9 Local diatom species richness of Arctic lake surface sediments, showing (left) richness as a function of latitude, and (right) site-specific richness. A LOESS smoother (blue line) with a span of 0.75 and a 95% confidence interval (grey shading) was applied to the data (left) to better highlight the general trend. Coloured circles on the map indicate the species richness at the sampling sites. State of the Arctic Freshwater Biodiversity Report - Chapter 4 - Page 37 - Figure 4-9

Figure 4-16 Map showing the magnitude of change in diatom assemblages for downcore samples, with beta diversity used as a measure of the compositional differences between samples at different depths along the core. Boundaries for the beta diversity categories are based on distribution quartiles (0-0.1, 0.1-1.24, 1.24-1.5, >1.5), where the lowest values (blue dots) represent the lowest degree of change in diatom assemblage composition along the length of the core in each lake. State of the Arctic Freshwater Biodiversity Report - Chapter 2 - Page 15 - Figure 2-1

Maximum LTA (long-term average) August air temperatures for the circumpolar region, with ecoregions used in the analysis of the SAFBR outlined in black. Source for temperature layer: Fick and Hijmans (2017). State of the Arctic Freshwater Biodiversity Report - Chapter 5 - Page 89 - Figure 5-5

The U.S. National Ice Center (NIC) is an inter-agency sea ice analysis and forecasting center comprised of the Department of Commerce/NOAA, the Department of Defense/U.S. Navy, and the Department of Homeland Security/U.S. Coast Guard components. Since 1972, NIC has produced Arctic and Antarctic sea ice charts. This data set is comprised of Arctic sea ice concentration climatology derived from the NIC weekly or biweekly operational ice-chart time series. The charts used in the climatology are from 1972 through 2007; and the monthly climatology products are median, maximum, minimum, first quartile, and third quartile concentrations, as well as frequency of occurrence of ice at any concentration for the entire period of record as well as for 10-year and 5-year periods. NIC charts are produced through the analyses of available in situ, remote sensing, and model data sources. They are generated primarily for mission planning and safety of navigation. NIC charts generally show more ice than do passive microwave derived sea ice concentrations, particularly in the summer when passive microwave algorithms tend to underestimate ice concentration. The record of sea ice concentration from the NIC series is believed to be more accurate than that from passive microwave sensors, especially from the mid-1990s on (see references at the end of this documentation), but it lacks the consistency of some passive microwave time series. Source: <a href="http://nsidc.org/data/G02172" target="_blank">NSIDC</a> Reference: National Ice Center. 2006, updated 2009. National Ice Center Arctic sea ice charts and climatologies in gridded format. Edited and compiled by F. Fetterer and C. Fowler. Boulder, Colorado USA: National Snow and Ice Data Center. Source: <a href="http://nsidc.org/data/G02172" target="_blank">NSIDC</a>

The number of key sites (monitored colonies) for seabirds (in 22 CSMP ecoregions) by country (a total of 125 sites). Sites are categorized as having fully, partially, or not met the CSMP criteria for parameters monitored (see 2.6.2). Data were from Appendix 3 of the CSMP (Irons et al. 2015); the degree of implementation may have changed at some sites since this summary was compiled. STATE OF THE ARCTIC MARINE BIODIVERSITY REPORT - <a href="https://arcticbiodiversity.is/findings/seabirds" target="_blank">Chapter 3</a> - Page 134 - Figure 3.5.2