Schematic surface circulation of the Arctic and Nordic Seas, including some of the major polynyas (gray shading) and the Greenland Sea and Iceland Sea deep convection sites (dark gray). Topography as in Figure 2.11, where place names can be found. Heavy lines indicate the principal circulation components, generally with larger transports than those depicted with finer lines. Acronyms: EGC, East Greenland Current; EIC, East Iceland Current; IC, Irminger Current; IFF, Iceland-Faroe Front; JMC, Jan Mayen Current; NAC, Norwegian Atlantic Current; and NIC, North Irminger Current. (After Rudels, 2001; Loeng et al., 2005; Rudels et al., 2010; Østerhus & Gammelsrød, 1999; and Straneo & Saucier, 2008. & Polynya locations from IAPP (2010) and Martin (2001)).

Overall schematic of (a) circulation, (b) water mass layers and transformation sites, and (c) water masses in potential temperature-salinity. Deep convection in the Greenland Sea in (b) has been replaced by mid-depth convection since the 1980s. Acronyms in (a): EGC, East Greenland Current; WSC, West Spitsbergen Current. Acronyms in (c): AW, Atlantic Water; AIW, Arctic Intermediate Water; ASW, Arctic Surface Water; DW, Deep Water; PIW, Polar Intermediate Water; PW, Polar Water. Source: From Aagaard, Swift, & Carmack (1985); amended by Schlichtholz and Houssais (2002).

(a) Potential temperature (°C) and (b) salinity in the Fram Strait in 1980. See Figure 2.11 for location of the strait. Source: From Mauritzen (1996).

(a) Potential temperature (°C) and (b) salinity across the southern Greenland Sea at 73.5°N in 1985. Source: From Mauritzen (1996).

(a) The Odden ice tongue off the east coast of Greenland, February 12, 1993. Source: From Wadhams et al. (1996). (b) Greenland Sea chimney region with 1988–1989 tomographic array location. (c) Mixed layer depth (with contours on bottom plane). Source: From Morawitz et al. (1996). (d) Potential temperature (°C, contour intervals of 0.2°C) time series at the array. Source: From Morawitz, Cornuelle, and Worcester (1996). Figures b, c, and d are © by the American Meteorological Society. Reprinted with permission. See also Figure S12.3 in the online supplement.

Schematic circulation in Hudson Bay and, peripherally, Baffin Bay. Source: From Straneo and Saucier (2008).

Track of the Fram (1893–1896). © www.frammuseum.no. Source: From Frammuseet (2003).

The ship was intentionally frozen into the ice in 1893 and drifted with the pack until 1896. © www.frammuseum.no. Source: From Frammuseet (2003).

Annual mean Arctic sea ice motion from 1979–2003 from Special Sensor Microwave Imager (SSM/I) passive microwave satellite data (extended from Emery, Fowler, & Maslanik, 1997; data from NSIDC, 2008a). Monthly means are shown in Figure S12.4 seen on the textbook Web site.

Mean sea level pressure (1979–1998) with mean ice buoy velocities for (a) winter (January-March) and (b) summer (July-September). ©American Meteorological Society. Reprinted with permission. Source: From Rigor, Wallace, and Colony (2002). (c) Mean wind vectors from ECMWF for 1983–1988. Source: From Zhang and Hunke (2001). Mean sea level pressure maps from Bitz et al. (2002) are also shown in Figure S12.5 seen on the textbook Web site.

Circulation schematics. (a) Subsurface Atlantic and intermediate layers of the Arctic Ocean and the Nordic Seas. Convection sites in the Greenland and Iceland Seas, and in the Irminger and Labrador Seas are also shown (light blue), as is a collection point for brine-rejected waters from the Barents Sea. Source: From Rudels et al. (2010). This figure can also be found in the color insert.

Circulation schematics.(b) Deep circulation; circled crosses indicate entry sites from dense shelf waters, and the Lomonosov Ridge overflow site. Source: From Rudels (2001).

Arctic Ocean and Nordic Seas: (a) potential temperature (°C), (b) salinity, (c) potential density referenced to the sea surface, (d) potential density referenced to 2000 dbar.After Aagaard et al. (1985).

Arctic Ocean and Nordic Seas:(e) station locations. Oxygen and CFC-11 are shown in Figure 12.16. Data sets were collected between 2000 and 2005. After Aagaard et al. (1985).

Arctic Ocean: (a) Potential temperature and (b) salinity profiles for the Canadian (dashed) and Eurasian Basins (solid). Station locations are shown in Figure 12.17a: dashed profiles are stations CaB and MaB and the solid profile is NaB. (c) Expanded potential temperature and salinity profile in the Canadian Basin (CaB in Figure 12.17a). After Steele et al. (2004).

(a) Schematic circulation of summer Bering Strait Water (blue) and Alaskan Coastal Water (red) during the positive phase of the Arctic Oscillation (Chapter S15 on the textbook Web site). Source: From Steele et al. (2004).

(b) Temperature (°C) of the shallow temperature maximum layer, which lies between 50 and 100 m depth, in the Canadian Basin. This figure can also be seen in the color insert. Source: From Steele et al. (2004).

Salinity along a section in the Chukchi Sea (March 1982), including a high salinity bottom layer created by brine rejection. Source: From Aagaard et al. (1985).

Atlantic Water in the Arctic. (a) Temperature maximum part of T-S diagram for core method analysis of flow direction for Atlantic Water, (b) circulation inferred from successive erosion of core shown in (a) stations 1 to 6, (c) depth, and (d) potential temperature (°C) of the Atlantic Water temperature maximum in the 1970s. Reprinted with permission; Polyakov et al. (2004) and Polyakov et al. (2010).

Atlantic Water in the Arctic. (c, d) are ©American Meteorological Society. Reprinted with permission; Polyakov et al. (2004) and Polyakov et al. (2010).

Vertical section across the Arctic and Nordic Seas. The section extends from the Chukchi Sea north of Bering Strait to the North Pole to Svalbard and Iceland (on the right). Corresponding sections of potential temperature, salinity and potential density were shown in Figure 12.11, along with a station location map. (a) Oxygen (μmol/kg), and (b) CFC-11 (pmol/kg). Station locations are shown in Figure

(a) Station map (1994 and 2001), (b) salinity, (c) potential temperature (°C), and (d) potential temperature-salinity. Acronyms: CaB, Canada Basin; MaB, Makarov Basin; NP, North Pole; AmB, Amundsen Basin; NaB, Nansen Basin; WSC, West Spitsbergen Current; GrS, Greenland Sea; IcS, Iceland Sea; and NAC, Norwegian Atlantic Current. This figure can also be found in the color insert. Expanded from Timmermans and Garrett (2006).

(a) Schematic of bottom water connections, including approximate sill depths. Potential density is relative to 2000 dbar. Arrows indicate mass fluxes overflowing into the basins and bottom arrows indicate geothermal heat flux. (b) Potential temperature (°C) and (c) salinity at stations in the Makarov and Canada Basins (MB and CB, respectively). The Makarov station “MB” is MaB in Figure 12.17a. ©American Meteorological Society. Reprinted with permission. Source: From Timmermans and Garrett (2006).

Volume transport budget. Red and orange are upper ocean inflows. Green is upper ocean outflow. Blue is intermediate/deep outflow. Transports are listed in Sverdrups. See Figure S12.7 on the textbook Web site for the color version.

Ice concentration in 1979 in: (a) late winter (March). Source: From NSIDC (2009a).

Ice concentration in 1979 in: (b) late summer (September). Source: From NSIDC (2009a).

Arctic ice ages: (a) 2004 and (b) cross-section of ice age classes (right) as a function of time (Hovmöller diagram), extending along the transect across the Arctic from the Canadian Archipelago to the Kara Sea shown in (a). This figure can also be seen in the color insert. Source: Extended from Fowler et al. (2004).

Polynyas in the Canadian Archipelago. Predominantly latent heat polynyas: North Water, Cape Bathurst. Tidally mixed polynyas: Committee Bay, Dundas Island, Lambert Channel and possibly Queens Channel, Bellot Strait, Fury, and Hecla Strait. Polynyas in the Barents, Kara, and Laptev Seas are illustrated in Figures S12.9–S12.11 on the textbook Web site. Source: From Hannah et al. (2009)