Number of terrestrial mammal species occupying low and high Arctic zones in each of the circumpolar Arctic regions. Conservation of Arctic Flora and Fauna, CAFF 2013 - Akureyri . Arctic Biodiversity Assessment. Status and Trends in Arctic biodiversity. - Mammals(Chapter 3) page 83

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>

Cumulative scores of various environmental and anthropogenic drivers of change of the benthic ecosystem across the eight Arctic Marine Areas (AMA). A cumulative score is the median score of sub-regions per AMA (Table 3.3.1). Median score for the whole Arctic is given in the centre. STATE OF THE ARCTIC MARINE BIODIVERSITY REPORT - <a href="https://arcticbiodiversity.is/findings/benthos" target="_blank">Chapter 3</a> - Page 100 - Figure 3.3.7

Trends in abundance of Arctic marine mammal Focal Ecosystem Components based on the most recent assessment for each recognized subpopulation of a species (red, declining trend; yellow, stable trend; green, increasing trend; grey, unknown trend). Number of subpopulations is given after species name. Each column is divided into equal segments, the sizes of which are not proportional to the size of the subpopulation. Ringed seal and bearded seal segments represent subspecies. Walrus segments represent subpopulations within subspecies. See Table 3.6.1 for details on abundance. STATE OF THE ARCTIC MARINE BIODIVERSITY REPORT - <a href="https://arcticbiodiversity.is/findings/marine-mammals" target="_blank">Chapter 3</a> - Page 156 - Figure 3.6.2

Abundance (birds/km2) of least auklets in four regions (see map) of the eastern Chukchi Sea, 1975-1981 and 2007-2012, based on at-sea surveys (archived in the North Pacific Pelagic Seabird Database). Figures provided by Adrian Gall, ABR, Inc. and reprinted with permission. STATE OF THE ARCTIC MARINE BIODIVERSITY REPORT - <a href="https://arcticbiodiversity.is/findings/seabirds" target="_blank">Chapter 3</a> - Page 138 - Box fig. 3.5.1 The shapefile outlines 4 regions of the eastern Chukchi Sea that were surveyed for seabirds during the open-water seasons of 1976-2012. We compared the density of seabirds in these regions among two time periods (1975-1981 and 2008-2012) to assess changes in seabird abundance over the past 4 decades. We also include a figure showing abundance of Least Auklets 1975-2012. Data are from the North Pacific Pelagic Seabird Database, maintained by the USGS (http://alaska.usgs.gov/science/biology/nppsd/index.php).

Bathymetric features, warm currents (red arrows), cold currents (blue arrows) and riverine inflow in the Arctic. Adapted from Jakobsen et al. (2012). Simplified Arctic Ocean currents (Fig. 2.1) show that the main circulation patterns follow the continental shelf breaks and margins of the basins in the Arctic Ocean. Different global models predict different types of changes, which can cause changes to Arctic ecosystems (AMAP 2013, Meltofte 2013). STATE OF THE ARCTIC MARINE BIODIVERSITY REPORT - <a href="https://arcticbiodiversity.is/marine" target="_blank">Chapter 2</a> - Page 22 - Figure 2.1

In 2017, the SAMBR synthesized data about biodiversity in Arctic marine ecosystems around the circumpolar Arctic. SAMBR highlighted observed changes and relevant monitoring gaps using data compiled through 2015. In 2021 an update was provided on the status of seabirds in circumpolar Arctic using data from 2016–2019. Most changes reflect access to improved population estimates, orimproved data for monitoring trends,independent of recognized trends in population size.

Vegetation monitoring occurs across the Arctic, but the duration of monitoring efforts is variable and is dependent upon both study design and access to resources. Although many field studies on vegetation have been conducted in the Arctic (Figure 3-5), not all can be considered monitoring since some recorded only select measurements over limited time frames. Studies reporting on abundance and composition of vegetation reflect a larger and more widespread geographical coverage than the typically more site-limited and time-consuming phenology studies (Figure 3-5). Geographical gaps in coverage of Siberia and large parts of the Canadian Arctic are evident. STATE OF THE ARCTIC TERRESTRIAL BIODIVERSITY REPORT - Chapter 3 - Page 34 - Figure 3.5

Subdivision of the Arctic into 28 sectors follows mainly the division used in the Pan Arctic Flora (PAF) project. In a few cases some islands are separated from their mainland in the beginning, thus representing very small sectors. Some of them have now been united like in the PAF project, for example Jan Mayen with Arctic Iceland and Bear Island with Svalbard. Others, like the Beringian Islands are still kept separate from the mainland on both sides. - <a href="http://www.caff.is/assessment-series/32-pan-arctic-checklist-of-lichens-and-lichenicolous-fungi" target="_blank"> Pan-Arctic Checklist of Lichens and Lichenicolous Fungi (2011)</a>

Temporal trends of arthropod abundance for three habitat types at Zackenberg Research Station, Greenland, 1996–2016. Data are grouped as the FEC ‘arthropod prey for vertebrates’ and separated by habitat type. Solid lines indicate significant regression lines at the p<0.05. Modified from Gillespie et al. 2020a. STATE OF THE ARCTIC TERRESTRIAL BIODIVERSITY REPORT - Chapter 3 - Page 39 - Figure 3.9