摘要:

Water vapor in the lower stratosphere was measured in situ by two aluminum oxide hygrometers mounted on the nose of an RB57 aircraft. Data were taken nearly continuously from January to May 1974 from an altitude of approximately 11–19 km as the aircraft flew between 70°N and 50°S over the land areas in the western hemisphere. Pseudomeridional cross sections of water vapor and temperature were derived from the flight data and show mixing ratios predominantly between 2 and 4 μg/g with an extreme range of 1–8 μg/g. Measurement precision was estimated by comparing the simultaneously measured values from the two flight hygrometer systems. Accuracy was estimated to be about ±40% at 19 km. A height‐averaged latitudinal cross section of water vapor indicates symmetry of wet and dry zones. This cross section is compared with other aircraft measurements and relates to meridional circulat

ISSN:0148-0227    

DOI:10.1029/JC082i034p05453

年代:1977

数据来源: WILEY

摘要:

A series of seven flights was conducted during 2 weeks in October 1976 to obtain synoptic thermal measurements of the Kuroshio and Oyashio fronts and to determine the distribution and physical properties of eddies formed by these fronts. Sea surface temperature was measured continuously with an airborne radiation thermometer, and airborne expendable bathythermographs (XBT's) provided subsurface temperature profiles. These data were supplemented with shipboard XBT and salinity temperature depth (STD) measurements of selected features. The Kuroshio was tracked from the coast of Japan eastward to 158°E. It had a width at the surface of approximately 75 km and exhibited two large anticyclonic meanders. Maximum horizontal temperature difference across the front was 12°C at 300 m; maximum horizontal gradient at this depth was 0.3°C/km. STD stations showed that the Kuroshio extended to a depth of 2500 m. The Oyashio Front was tracked eastward to 154°E, and at depths less than 100 m it displayed horizontal temperature gradients equal to those of the Kuroshio. The Oyashio was observed to be a much shallower feature, however, weakening rapidly with depth. A total of nine eddies generated by both fronts was found: three Kuroshio cold eddies, three Kuroshio warm eddies, two Oyashio warm eddies, and one Oyashio cold eddy. They were of varying ages and ranged in size from 100 to 240 km. This is believed to be the largest number of eddies ever observed east of Japan and indicates that these features occupy a significant portion of this complex frontal sys

ISSN:0148-0227    

DOI:10.1029/JC082i034p05459

年代:1977

数据来源: WILEY

摘要:

A recent twofold increase in the number of temperature observations available in the Gulf of Mexico has prompted a reappraisal of several ideas regarding the temporal variability of the Loop Current in the eastern gulf and the anticyclonic gyre in the western gulf. The analysis includes both synoptic data drawn from 47 cruises in the eastern gulf and monthly maps of temperature at 200 m prepared from observations over the entire gulf. It is found that on average the penetration of the Loop Current into the gulf increases during the winter and spring, reaching a maximum in the early summer, at which time a large anticyclonic eddy probably separates from the loop. It is also found that there are substantial deviations from this average sequence of events; during the past dozen years the period between eddy separations has been as short as 8 months and as long as 17 months. The data coverage of the western gulf is sparse, but there is evidence for the year‐round persistence of the anticyclonic gyre and some indications that the gyre may be strongest in summer and winte

ISSN:0148-0227    

DOI:10.1029/JC082i034p05469

年代:1977

数据来源: WILEY

摘要:

Two undisturbed sediment cores at 220 and 200 m in the deepest basin of Saanich Inlet, British Columbia, were collected by a box corer. In the upper 30 cm the sediment porosity exhibited an abrupt decrease with depth due to compaction. The corrected depth of sediments without compaction was calculated. The210Pb profiles were plotted against the corrected depth in order to determine the accumulation rate at the surface in cm yr−1. The sedimentation rate in g cm−2yr−1was calculated from the accumulation rate. A sedimentation rate of 0.093 g cm−2yr−1was obtained at the end of the deep basin away from the sill entrance and 0.27 g cm−2yr−1near the sill of the deep basin. The Pb, Cu, Cd, and Hg contents in the sediment cores appeared to decrease with depth. A present metal flux of 1.9–5.1 dpm cm−2yr−1was inferred for210Pb, 3.6–11 μg cm−2yr−1for stable Pb, 6.3–14 for Cu, 0.11–0.48 for Cd, and 0.029–0.072 for Hg. When some recent measurements of heavy metal concentrations in the seawater near the sill of the deep basin of Saanich Inlet were used, a residence time in the water column of 0.08 years was inferred for210Pb, 0.07 for stable Pb, 0.

ISSN:0148-0227    

DOI:10.1029/JC082i034p05477

年代:1977

数据来源: WILEY