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Byline: Sachiko Oguma (1), Toru Suzuki (1), Sydney Levitus (2), Yutaka Nagata (1) Keywords: Subarctic region; skewed occurrence frequency; quality control; range check; water intrusion Abstract: In a previous paper (Oguma and Nagata, 2002), it was shown that frequency distributions of temperature and salinity in the sea off Sanriku Coast, Japan are skewed, and sometimes observed values exceed m + 5[sigma] (m = mean, [sigma] = standard deviation). This means that, if we apply a 3[sigma] criterion for a range check, many real data would be lost. We have expanded our analysis to the subarctic North Pacific, the subarctic North Atlantic and their surrounding areas, by computing the distributions of skewness and kurtosis. It is found that the region of high positive skewness extends in an east-north-east direction in the Mixed Water Region from off Sanriku, and reaches to about 155degE. A high negative skewness zone is recognized along the southern margin of the Kuroshio Extension. These are thought to be generated by the breaking of the meander of the Kuroshio Extension and subsequent ejection of warm and cold eddies to the north and south, respectively. Other high positive skewness areas are found to the south of Kuril Islands and in the Japan Sea. These are generated due to very sharp vertical gradients of temperature and salinity. The situation in the North Atlantic is very similar to the North Pacific, though the detailed nature is changed due to differences of oceanographic condition. The effect of grid size on the skewed nature of the distribution is also discussed. Author Affiliation: (1) Marine Information Research Center, JHA, 7-15-4 Ginza, Chuo-ku, Tokyo, 104-0061, Japan (2) World Data Center for Oceanography, NODC/NOAA, Silver Spring, MD, 20910-3282, U.S.A Article History: Registration Date: 06/10/2004

Analyses of historical ocean temperature data at a depth of 125 meters in the North Atlantic Ocean indicate that from 1950 to 1990 the subtropical and subarctic gyres exhibited linear trends that were opposite in phase. In addition, multivariate analyses of yearly mean temperature anomaly fields between 20 ° N and 70 ° N in the north Atlantic show a characteristic space-time temperature oscillation from 1947 to 1990. A quasidecadal oscillation, first identified at Ocean Weather Station C, is part of a basin-wide feature. Gyre and basin-scale variations such as these provide the observational basis for climate diagnostic and modeling studies., Levitus et al. (1) presented analyses of temperature time series data at Ocean Weather Station C (OWS C) that indicated the interannual variability of upper ocean thermal structure at this [...]

We compared the temporal variability of the heat content of the world ocean, of the global atmosphere, and of components of Earth's cryosphere during the latter half of the 20th century. Each component has increased its heat content (the atmosphere and the ocean) or exhibited melting (the cryosphere). The estimated increase of observed global ocean heat content (over the depth range from 0 to 3000 meters) between the 1950s and 1990s is at least one order of magnitude larger than the increase in heat content of any other component. Simulation results using an atmosphere-ocean general circulation model that includes estimates of the radiative effects of observed temporal variations in greenhouse gases, sulfate aerosols, solar irradiance, and volcanic aerosols over the past century agree with our observation-based estimate of the increase in ocean heat content. The results we present suggest that the observed increase in ocean heat content may largely be due to the increase of anthropogenic gases in Earth's atmosphere., Studies using instrumental data to document a warming of Earth's climate system due to increasing concentrations of greenhouse gases (GHGs) have focused on surface air temperature and sea surface temperature [...]

We quantify the interannual-to-decadal variability of the heat content (mean temperature) of the world ocean from the surface through 3000-meter depth for the period 1948 to 1998. The heat content of the world ocean increased by ~2 x [10.sup.23] joules between the mid-1950s and mid-1990s, representing a volume mean warming of 0.06 ° C. This corresponds to a warming rate of 0.3 watt per meter squared (per unit area of Earth's surface). Substantial changes in heat content occurred in the 300- to 1000-meter layers of each ocean and in depths greater than 1000 meters of the North Atlantic. The global volume mean temperature increase for the 0- to 300-meter layer was 0.31 ° C, corresponding to an increase in heat content for this layer of ~ 1023 joules between the mid-1950s and mid-1990s. The At[antic and Pacific Oceans have undergone a net warming since the 1950s and the Indian Ocean has warmed since the mid-1960s, although the warming is not monotonic., The Intergovernmental Program on Climate Change (1), the World Climate Research Program CLIVAR (2), and the U.S. National Research Council (3) have identified the role of the ocean as being [...]