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    Extensive oil and gas activity has occurred in the Arctic, primarily land-based, with Russia extracting 80% of the oil and 99% of the gas to date (AMAP 2008). Furthermore, the Arctic still contains large petroleum hydrocarbon reserves and potentially holds one fifth of the world’s yet undiscovered resources, according to the US Geological Survey (USGS 2008) (Fig. 14.4). While much of the currently known Arctic oil and gas reserves are in Russia (75% of oil and 90% of gas; AMAP 2008), more than half of the estimated undiscovered Arctic oil reserves are in Alaska (offshore and onshore), the Amerasian Basin (offshore north of the Beaufort Sea) and in W and E Greenland (offshore). More than 70% of the Arctic undiscovered natural gas is estimated to be located in the W Siberian Basin (Yamal Peninsula and offshore in the Kara Sea), the E Barents Basin and in Alaska (offshore and onshore) (AMSA 2009). Associated with future exploration and development, each of these regions would require vastly expanded Arctic marine operations, and several regions such as offshore Greenland would require fully developed Arctic marine transport systems to carry hydrocarbons to global markets. In this context, regions of high interest for economic development face cumulative environmental pressure from anthropogenic activities such as hydrocarbon exploitation locally, together with global changes associated with climatic and oceanographic trends. Conservation of Arctic Flora and Fauna, CAFF 2013 - Akureyri . Arctic Biodiversity Assessment. Status and Trends in Arctic biodiversity. - Marine ecosystems (Chapter 14 - page 501). Figure adapted from the USGS

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    The MODIS Land Cover Type product is created yearly using three landclassification schemes; the International Geosphere Biosphere Programme (IGBP)classification scheme, the Univertiy of Maryland (UMD) classification scheme, and aMODIS-derived Leaf Area Index /Fraction of Photosynthetically Active Radiation(LAI/fPAR) classification scheme (Table 3). The International Geosphere Biosphere Programme (IGBP) identifies seventeenland cover classes, including eleven natural vegetation classes, three non-vegetated landclasses, and three developed land classes. The product provided is derived using the samealgorithm as the 500 m Land Cover Type (MOD12Q1), but is on a 0.05° Climate Model Grid(CMG), that has been clipped to the pan-Arctic extent. The UMD classification scheme issimilar to the IGBP classification scheme, but it excludes the Permanent wetlands,Cropland/Natural vegetation mosaic, and the Snow and ice classes. The LAI/fPARclassification scheme is the smallest of the three, and focuses on forest structure; it only haseleven classes. All three land cover classification schemes are provided, but the IGBPclassification scheme is the most amenable to the Pan-Arctic region.

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    We present the first digital seafloor geomorphic features map (GSFM) of the global ocean. The GSFM includes 131,192 separate polygons in 29 geomorphic feature categories, used here to assess differences between passive and active continental margins as well as between 8 major ocean regions (the Arctic, Indian, North Atlantic, North Pacific, South Atlantic, South Pacific and the Southern Oceans and the Mediterranean and Black Seas). The GSFM provides quantitative assessments of differences between passive and active margins: continental shelf width of passive margins (88 km) is nearly three times that of active margins (31 km); the average width of active slopes (36 km) is less than the average width of passive margin slopes (46 km); active margin slopes contain an area of 3.4 million km2 where the gradient exceeds 5°, compared with 1.3 million km2 on passive margin slopes; the continental rise covers 27 million km2 adjacent to passive margins and less than 2.3 million km2 adjacent to active margins. Examples of specific applications of the GSFM are presented to show that: 1) larger rift valley segments are generally associated with slow-spreading rates and smaller rift valley segments are associated with fast spreading; 2) polar submarine canyons are twice the average size of non-polar canyons and abyssal polar regions exhibit lower seafloor roughness than non-polar regions, expressed as spatially extensive fan, rise and abyssal plain sediment deposits – all of which are attributed here to the effects of continental glaciations; and 3) recognition of seamounts as a separate category of feature from ridges results in a lower estimate of seamount number compared with estimates of previous workers. Reference: Harris PT, Macmillan-Lawler M, Rupp J, Baker EK Geomorphology of the oceans. Marine Geology.