Colored Dissolved Organic Matter (CDOM) is a measurement of the absorption of light in the UV and visible spectrum by the colored components of dissolved organic carbon. It is essentially the yellow substance in water as a result of decaying detritus. It is important to measure because it limits the amount of sunlight penetration, and thus restricts the growth of plankton populations. It is measured in a unit-less CDOM index. Data generated as part of CAFFs Circumpolar Biodiversity Monitoring Program (CAFF) and its Land Cover Change Initiative (LCC) Trends visible in the MODIS dataset show an overall decrease in the mean CDOM from 2003 to 2012, with a percent change of -31.7%. This trend can be seen in Figure 40. This decrease corresponds to the increase in total yearly primary productivity (Figure 30), as a decrease in the CDOM allows for sunlight to penetrate deeper into the water, boosting chlorophyll concentrations and thus primary productivity.

Arctic Biodiversity Assessment (ABA) 2013. Figure 4.2. Major flyways of Arctic birds. Bird migration links Arctic breeding areas to all other parts of the globe (adapted from ACIA 2005). Conservation of Arctic Flora and Fauna, CAFF 2013 - Akureyri . Arctic Biodiversity Assessment. Status and Trends in Arctic biodiversity. - Birds(Chapter 4) page 146

The two species of murres, thick-billed Uria lomvia and common U. aalge, both have circumpolar distributions, breeding in Arctic, sub-Arctic and temperate seas from alifornia and N Spain to N Greenland, high Arctic Canada, Svalbard, Franz Josef Land and Novaya Zemlya (Box 4.3 Fig. 1). Conservation of Arctic Flora and Fauna, CAFF 2013 - Akureyri . Arctic Biodiversity Assessment. Status and Trends in Arctic biodiversity. - Birds(Chapter 4) page 163

Arctic Biodiversity Assessment (ABA) 2013. Table 9.5. Species numbers of species-rich moss genera and families. Numbers highlighted in grey fields are used in calculating the percentage of the total moss flora. Listed are Splachnum, genera with at least 10 species and families with at least nine species. Conservation of Arctic Flora and Fauna, CAFF 2013 - Akureyri . Arctic Biodiversity Assessment. Status and Trends in Arctic biodiversity. - Plants(Chapter 9) page 333

Trends in water temperature and salinity (A) and density of phytoplankton of two size ranges (B), Canada Basin, 2004 to 2008. Stratification of the water column increased throughout the Canada Basin over a recent five-year period, accompanied by a change in phytoplankton communities. The upper ocean layer showed trends of increased temperature and decreased salinity (Figure 18A), which combine to make this layer progressively less dense. The layer of water below this did not change in density over this period (not shown). The larger size class of phytoplankton (which would include diatoms) decreased in abundance, while the smaller types of plankton increased (Figure 18B). In addition to the trends shown, nutrient content in the upper ocean water layer decreased. Abundance of microbes (bacteria and similar organisms) that subsist on organic matter increased. Total phytoplankton biomass, however, remained unchanged. If this trend towards smaller species of phytoplankton and microbes is sustained, it may lead to reduced production of zooplankton, an impact that would be transmitted through the food web to birds, fish and mammals. Published in the Life Linked to Ice released in 2013, page 30. Life Linked to Ice: A guide to sea-ice-associated biodiversity in this time of rapid change. CAFF Assessment Series No. 10. Conservation of Arctic Flora and Fauna, Iceland. ISBN: 978-9935-431-25-7.

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).

Circumpolar distribution of arctic char species complex Salvelinus alpinus, and related species. - <a href="http://www.caff.is/assessment-series/10-arctic-biodiversity-assessment/211-arctic-biodiversity-assessment-2013-chapter-6-fishes" target="_blank"> Arctic Biodiversity Assessment, Chapter 6: Fishes</a>

The distribution of Arctic char species complex, sensu stricto, and the location of introduced populations. Published in the Arctic Biodiversity trends 2010, Indicator #06 Arctic char, page 41 - released in May 2010

The number of species depends partly on what has been studied. Proportions vary somewhat around the Arctic, but diatoms and dinoflagellates are the most diverse groups everywhere. The greatest sampling effort has been in the Laptev Sea, Hudson Bay, and the Norwegian sector of the Barents Sea. Species shown are among the most commonly recorded. Published in the Life Linked to Ice released in 2013, page 26. Life Linked to Ice: A guide to sea-ice-associated biodiversity in this time of rapid change. CAFF Assessment Series No. 10. Conservation of Arctic Flora and Fauna, Iceland. ISBN: 978-9935-431-25-7.

Figure 4.1. Avian biodiversity in different regions of the Arctic. Charts on the inner circle show species numbers of different bird groups in the high Arctic, on the outer circle in the low Arctic. The size of the charts is scaled to the number of species in each region, which ranges from 32 (Svalbard) to 117 (low Arctic Alaska). CAFF 2013. Arctic Biodiversity Assessment. Status and Trends in Arctic biodiversity. Conservation of Arctic Flora and Fauna, Akureyri - Birds (Chapter 4) page 145