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971.
Martin Schwarzbach 《International Journal of Earth Sciences》1948,35(2):120-121
Ohne Zusammenfassung 相似文献
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Ohne Zusammenfassung 相似文献
974.
Keeton J. A. Searle R. C. Peirce C. Parsons B. White R. S. Sinha M. C. Murton B. J. Parson L. M. 《Marine Geophysical Researches》1997,19(1):55-64
We present a series of 1:200,000 scale maps of the bathymetry of the Reykjanes Ridge. The data are divided into four maps, extending 630 km along the ridge axis and between 30 and 100 km off-axis. This compilation of bathymetry data is extremely detailed, gridded at approximately 100 m resolution, and with almost no gaps. The Reykjanes Ridge is one of the best examples of a hotspot-dominated ridge, whose characteristics are influenced by its proximity to the Iceland plume. Many fundamental questions may be addressed at the Reykjanes Ridge, which is why the BRIDGE programme identified it as one of its four regional projects. These maps represent a BRIDGE contribution to the general scientific community. 相似文献
975.
Patrick Christie David L. Fluharty Alan T. White Liza Eisma-Osorio William Jatulan 《Marine Policy》2007
This analysis documents the reasons for emerging interest in ecosystem-based fisheries management (EBFM) and relates this management model to others. It highlights the central challenges to EBFM in the tropical context and examines an ongoing project, Fisheries Improved for Sustainable Harvest (FISH), in the Philippines—likely the first EBFM project in the tropics. The Philippine legal and institutional context provides major governance challenges to EBFM, especially as management is scaled up. A monitoring framework with process and output criteria is applied to FISH to establish progress to date. Major institutional and governance challenges for EBFM will require monitoring, evaluation, and adaptation. 相似文献
976.
Warren B. White Daniel R. Cayan Peter P. Niiler Gary Lagerloef David Legler 《Progress in Oceanography》2005,64(1):1-29
This study quantifies uncertainties in closing the seasonal cycle of diabatic heat storage (DHS) over the Pacific Ocean from 20°S to 60°N through the synthesis of World Ocean Circulation Experiment (WOCE) reanalysis products from 1993 to 1999. These products are DHS from Scripps Institution of Oceanography (SIO); near-surface geostrophic and Ekman currents from Earth and Space Research (ESR); and air-sea heat fluxes from Comprehensive Ocean-Atmosphere Data Set (COADS), National Centers for Environmental Prediction (NCEP), and European Center for Mid-Range Weather Forecasts (ECMWF). With these products, we compute residual heat budget components by differencing long-term monthly means from the long-term annual mean. This allows the seasonal cycle of the DHS tendency to be modeled. Everywhere latent heat flux residuals dominate sensible heat flux residuals, shortwave heat flux residuals dominate longwave heat flux residuals, and residual Ekman heat advection dominates residual geostrophic heat advection, with residual dissipation significant only in the Kuroshio-Oyashio current extension. The root-mean-square (RMS) of the differences between observed and model residual DHS tendencies (averaged over 10° latitude-by-20° longitude boxes) is <20 W m−2 in the interior ocean and <100 W m−2 in the Kuroshio-Oyashio current extension. This reveals that the residual DHS tendency is driven everywhere by some mix of residual latent heat flux, shortwave heat flux, and Ekman heat advection. Suppressing bias errors in residual air-sea turbulent heat fluxes and Ekman heat advection through minimization of the RMS differences reduces the latter to <10 W m−2 over the interior ocean and <25 W m−2 in the Kuroshio-Oyashio current extension. This reveals air-sea temperature and specific humidity differences from in situ surface marine weather observations to be a principal source of bias error, overestimated over most of ocean but underestimated near the Intertropical Convergence Zone. 相似文献
977.
Measurements of near-seabed currents at different carbonate mound locations have demonstrated the presence and influence of
bottom-magnified diurnal-period tidal motions. These bottom-trapped waves occur at a depth where the product of local vertical
density stratification and seabed slope is a maximum. The seabed currents are magnified significantly if the diurnal forcing
period is resonant with the combination of stratification and seabed slope. At the Belgica mounds (eastern Porcupine Sea Bight),
there is a correlation between the cross-slope alignment of individual carbonate mounds and the direction of the major axis
of the largest (diurnal) tides. The pattern suggests that the enhanced tidal currents play a major role in the shape of developing
mounds over a long time period. A similar relation appears to hold at the Logachev mounds (SE Rockall Bank), although less
clear because tides are not amplified to the same degree. At other mound locations where enhanced diurnal currents are not
present, a more irregular distribution is observed. This suggests that the diurnal currents may be important only at certain
carbonate mound locations, and that at these locations a more distinctive alignment of mound structures is produced. 相似文献
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