Chemical characteristics of water masses in the Amerasian Basin of the Arctic Ocean

Abstract

Detailed vertical profiles of hydrographic data and routine chemical parameters (oxygen, nutrients) were taken in the Amerasian basin of the Arctic Ocean and in the Bering Strait and Chukchi Sea. Correlations of these chemical profiles with water mass sources and mixing processes are postulated. The chemical parameters show that the water of the sharp temperature maximum at about 75‐meter depth is chemically a mixture of the arctic surface water and core water from about 160 meters. This core water corresponds to the temperature minimum and nutrient maximum and is of Bering Strait‐Chukchi Sea origin. Chemical parameters clearly show that the temperature maximum and minimum simply reflect differing thermal regimes existing in the Chukchi. Extremely close vertical sampling has shown intriguing detail in the oxygen, temperature, salinity, and nutrient profiles in the area of the very sharp oxygen minimum occurring at about 205 meters. Temperature‐salinity and chemical plots of the close‐interval data identify a core of water at approximately 230 meters that is mixing above with Bering core water at 160 meters and below with the Atlantic core water at about 500 meters. Thus the oxygen minimum appears to be at least partly due to advection of shelf water into the basin rather than to in situ oxidation alone.

Shelf–Basin interaction along the East Siberian Sea

“…One of the most pronounced signatures of the upper halocline of the central Arctic Ocean is a silicate maximum, which was first reported in 1968-1969 from observations made from the drifting T-3 ice island in the Canada Basin (Kinney et al, 1970). In 1979 the silicate maximum was observed during the LOREX study over the Lomonosov Ridge and into the fringe of the Amundsen Basin (Moore et al, 1983).…”

The Arctic Ocean marine carbon cycle: evaluation of air-sea CO<sub>2</sub> exchanges, ocean acidification impacts and potential feedbacks

“…The central basin of the Arctic Ocean is strongly stratified (Kinney et al, 1970;Aagaard et al, 1981;Jones and Anderson, 1986;Anderson et al, 1989Anderson et al, , 1999Aagaard and Carmack, 1994;Schlosser et al, 1995;Codispoti et al, 2005). In the Eurasian and Canada Basin (Fig.…”

Deep water circulation and composition in the Arctic Ocean by dissolved barium, aluminium and silicate

“…The halocline may be divided into an upper and a lower halocline using salinity and nutrients. Salinities of 32.5 to 33.5 and a nutrient maximum imprinted in the Chukchi and East Siberian Seas characterize the Pacific origin of the upper halocline (Jones and Anderson, 1986;Jones et al, 1991;Kinney and Burrell, 1970;Moore et al, 1983;Morison et al, 1998). Pacific waters of winter origin tend to enter the interior Arctic below the upper mixed layer because they are generally more saline (Weingartner et al, 1998).…”