949 resultados para Marriage records


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We deployed autonomous temperature sensors at black smoker chimneys, cracks, and diffuse flow areas at the Lucky Strike hydrothermal field (Mid-Atlantic Ridge, ~37°17'N) between summer 2009 and summer 2012 and contemporaneously measured tidal pressures and currents as part of the long-term MoMAR experiment to monitor hydrothermal activity. We classify the temperature data according to the hydrogeologic setting of the measurement sites: a high-temperature regime (>190°C) representing discharge of essentially unmixed, primary hydrothermal fluids through chimneys, an intermediate-temperature regime (10-100°C) associated with mixing of primary fluids with cold pore fluids discharging through cracks, and a low-temperature regime (<10°C) associated with a thermal boundary layer forming over bacterial mats associated with diffuse outflow of warm fluids. Temperature records from all the regimes exhibit variations at semi-diurnal tidal periods, and cross-spectral analyses reveal that high-temperature discharge correlates to tidal pressure while low-temperature discharge correlates to tidal currents. Intermediate-temperature discharge exhibits a transitional behavior correlating to both tidal pressure and currents. Episodic perturbations, with transient temperature drops of up to ~150°C, which occur in the high-temperature and intermediate-temperature records, are not observed on multiple probes (including nearby probes at the same site), and they are not correlated with microearthquake activity, indicating that the perturbation mechanism is highly localized at the measurement sites within the hydrothermal structures. The average temperature at a given site may increase or decrease at annual time scales, but the average temperature of the hydrothermal field, as a whole, appears to be stable over our 3 year observation period.

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The first meteorological station in the Vernagtferner basin, called 'Gletschermitte' was run from 1968 to 1987. It was positioned on a small rock in the western part of the glacier at an elevation of 3078 m a.s.l. The coordinates were 46.868939° N (Latitude) and 10.802986° E (Longitude). The following parameters were recorded mainly during the summer months: Wind speed and wind direction, air temperature and humidity of the air and precipitation. The records of the first four parameters comprise hourly values from 1968 to 1986 /1987, daily sums of precipitation run from 1977 to 1987. All quantities were recorded on paper chart, i.e. 'Woelfle-Windschreiber' for the wind components, mechanically driven thermo-hygrographs (1968 to 1975) and 'BTW-Langzeit-Thermo-Hygrograph' (1977 to 1987) for temperature and humidity, Belfort analogue weighing gauge for precipitation. In 1976, air temperature was recorded on a Schenk paper chart recorder. In addition, photographs of the eastern part of Vernagtferner were taken once a day in summer between 1981 and 1986.

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Several high-resolution proxy environmental records have been obtained for the last 35 kyr from ODP Hole 658C, a well-studied site ca. 200 km off Cap Blanc, NW Africa. The collective assessment based on the marine proxies (UK'37 SST, contents of TOC and chlorins, Upwelling Radiolarian Index and the percentage of Florisphaera profunda), surprisingly indicates that the last glacial maximum (LGM) was characterized by warmer sea surface temperature (SST), weaker upwelling, and lower marine productivity, compared with the preceding older glacial and subsequent deglaciation periods. Of the terrigenous proxies, the mean grain size of the non-carbonate fraction and the terrigenous alkane content indicate that wind strength and aridity were high. The weaker upwelling at the 658 site during the LGM may have resulted from changes in the strength and direction of the wind systems and/or shifts in the position and geometry of the upwelling cell.