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    Sea level height data from DART Station 46401 - D171 at 46.630N 170.79W. Water Column Height is at 46401 meters. Events data are also provided if any are available. Data are recorded in pounds per square inch absolute (PSIA), but are displayed in meters after applying a constant 670.00 mm of water/PSIA conversion factor.DART system consist of an anchored seafloor bottom pressure recorder (BPR) and a companion moored surface buoy for real-time communications. An acoustic link transmits data from the BPR on the seafloor to the surface buoy. The data are then relayed via a GOES satellite link to ground stations, which demodulate the signals for immediate dissemination to NOAA's Tsunami Warning Centers, NDBC, and PMEL.PMEL DART program website http://www.pmel.noaa.gov/tsunami/Dart/ Real-time data is available at the National Data Buoy Center http://www.ndbc.noaa.gov/dart.shtml

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    This data set contains total column aerosol optical thickness gridpoint values calculated from channel 2 albedo observations (using the SST cloud clearing algorithm). The analyzed weekly fields are at 100km resolution. The Office of Satellite Data Processing and Distribution (OSDPC) keeps this data for a month, then sends it to the National Climatic Data Center (NCDC) for archiving. For current data, contact John Sapper at OSDPC, telephone 301-457-0914 ext.148, e-mail: john.sapper@noaa.gov. For archived data contact Thomas Ross at NCDC, telephone 828-271-4499, e-mail: tom.ross@noaa.gov.

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    The surface ocean plays an important role in the global biogeochemical sulfur cycle. Gaseous sulfur compounds emitted from the ocean are thought to be a major source of sulfate aerosol in the marine troposphere. Establishing the relationship between gaseous sulfur emissions, atmospheric sulfate concentrations, and aerosol particle populations is not only important in defining the ocean/atmosphere flux of sulfur, but also for the effects these particles may have on local cloud reflectivity, aerosol optical depth, and global climate. During 1982-1985, dimethylsulfide (DMS) concentrations were measured in over 1000 Pacific Ocean surface seawater samples. The data have been tabulated to take into account both regional and seasonal variations in concentration. These concentration data, combined with area-weighted summer and winter exchange coefficients, yield a net ocean to atmosphere DMS flux in the North Pacific Ocean of 0.12 ± 0.06 Tmol/a. Extrapolating this calculation by regional areas to the global ocean yields a net DMS flux of 0.50 ± 0.25 Tmol/a, less than earlier estimates of 1.2 Tmol/a, but still consistent with estimates of non-sea-salt sulfate deposition and model studies of the marine atmospheric sulfur budget. Using these regional and seasonal DMS concentration data, it appears that oceanic DMS emissions are positively correlated with atmospheric aerosol particle populations. The major components of the atmospheric biogeochemical sulfur cycle were measured along the coast of Washington State during May of 1987. Combining simultaneous measurements of the key oceanic and atmospheric sulfur species, it is possible to show the importance of DMS emissions on the cycling of sulfur in the marine boundary layer.Simultaneous measurements of oceanic DMS, atmospheric aerosol sulfate and the size-resolved physical properties of the aerosol were made in the equatorial Pacific during July 1987. Under light and variable winds, in an area free of continental and anthropogenic air masses, an observed increase in oceanic DMS concentrations preceded simultaneous increases in non-sea salt sulfate aerosol, the fraction of volatile sub-micrometer (sub-µm) aerosol, the aerosol particle population, and the mean particle diameter of the sub-µm aerosol. These data support the hypothesis that oceanic DMS is the source of background marine sulfate aerosols formed from gas-to-particle conversions in the atmosphere.Reference: Bates, T.S. (1988): Evidence for the climatic role of marine biogenic sulfur. Ph.D. Dissertation, University of Washington, Seattle, 99 pp.PMEL Publication Contribution #1152

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    While massive forest fires have so far ravaged more than two million acres across the American West in one of the worst fire season in years, wildfires in Alaska have scorched just over 200,000 acres across the state. Typically, Alaska fires are among the nation's largest, with single burns blackening hundreds of thousands of acres. As Sonya Senkowsky reports in this week's Arctic Science Journeys Radio, northern forest fires could be a significant source of the greenhouse gas, carbon dioxide.

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    Wintertime precipitation events in the Mackenzie River basin (MRB) play an important role in the hydrology of the region because they contribute substantially to water storage prior to the spring runoff maximum. The Mesoscale Compressible Community (MC2) Model is used to simulate a representative wintertime MRB precipitation event. The MC2 simulation, gridded analyses, and raw observations are used to (i) document meteorological conditions associated with the precipitation event, (ii) assess the ability of the model to reproduce the precipitation event and antecedent large-scale moisture transport, and (iii) identify which planetary- and synoptic-scale features are responsible for the observed moisture transport using piecewise quasigeostrophic potential vorticity (QGPV) inversion. Precipitation in the MRB develops north of an intense frontal boundary as a southwesterly flow of moisture originating over the Pacific Ocean is lifted over cold, dense arctic air near the surface. A lee cyclone forms along the frontal boundary as an upper-tropospheric disturbance approaches from the west. The MC2 model adequately represents the lee cyclone formation, the observed precipitation event, and large-scale moisture transport, as determined through comparison of the model output with analyses and raw observations. A plume of moisture advances northeastward from the subtropical Pacific Ocean toward the MRB during the 24ヨ36-h period prior to the precipitation event. Piecewise QGPV inversion demonstrates that the background climatological flow and a cyclonic QGPV anomaly located over the eastern Pacific Ocean are associated with the initial moisture transport into the Gulf of Alaska. Later, a second cyclonic QGPV anomaly centered over the Gulf of Alaska is associated with moisture transport from over the Gulf of Alaska into the MRB. The moisture flux is generally largest in the lower troposphere owing to the larger concentration of water vapor there. The Rocky Mountains, located west of the MRB, block much of the eastward moisture transport below the 800-hPa level. Moisture transport in the layer between 700 and 800 hPa is therefore crucial for MRB precipitation in situations where the moisture originates over the Pacific. QGPV inversions based on a vertically partitioned QGPV field indicate that QGPV anomalies located below the dynamic tropopause are associated with larger moisture transport at the 700-hPa level than their tropopause-based counterparts.

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    The NEAR-GOOS Regional Real Time Database Base (RRTDB) contains data collected at the Japan Meteorological Agency (JMA) through Global Telecommunication System (GTS) of the World Meteorological Organization, that data that the participating institutes have contributed and some products by JMA. The data which have resided in the NEAR-GOOS RRTDB for 30 days are transferred to the NEAR-GOOS Regional Delayed Mode Data Base (RDMDB) at http://near-goos1.jodc.go.jp/ and maintained for user access. First time users must register to gain database access.

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    According to project of transport connection of USA and Russia across Bering Strait the three designs are considered: dam, underground tunnel, bridge. In all this cases a human influence on environment is great and must be accounted for even now. The paper presents the estimated changes of ice movements in Bering Strait. (DBO).

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    Ocean model for the Earth Simulator (OFES) is a global 0.1x0.1 degree model forced by NCEP winds. OFES was run for 50 years to provide various outputs including climatology and hindcast model outputs at 0.1 and 0.5 degree grid.Note: In the ocean, typical size of eddies is horizontal 100 km order, which plays significant role on momentum and heat transportation. In order to reproduce eddies, the horizontal resolution of OFES is as small as 10 km. Meanwhile, in order to simulate the entire ocean, the whole globe except the two poles was set to be the calculation area. In the ocean simulation by OFES, various currents such as the Kuroshio south of Japan as well as fairly small eddies of 100 km order are all well reproduced.

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    Atmospheric action center (AAC) are important for general atmospheric circulation. In Asian Pacific region four AACs are distinguished: North Pacific high, Aleutian low (permanent), winter Asian high and summer Asian low (seasonal). Mean yearly pressure, longitudinal and latitudinal anomalies of AACs registered in 1947-1994 are studied on the basis of World Hydrometeorological Data Center B.

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    JAMSTEC provides it's R/V MIRAI cruise reports and data sets on-line. Cruise dates range from 30 October 1998 to 05 September 2005. Cruise areas are mainly of the Pacific Ocean.Data provided include general oceanographical, geophysical, and meteorological observations, and chemical and sediment analyses.