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81.
Theresa L. Sinicrope Pamela G. Hine R. Scott Warren William A. Niering 《Estuaries and Coasts》1990,13(1):25-30
The restoration of a 20 ha tidal marsh, impounded for 32, yr, in Stonington, Connecticut was studied to document vegetation change 10 yr after the reintroduction of tidal flushing. These data were then compared to a 1976 survey of the same marsh when it was in its freshest state and dominanted byTypha angustifolia. Currently,T. angustifolia remains vigorous only along the upland borders and in the upper reaches of the valley marsh. Live coverage ofT. angustifolia has declined from 74% to 16% and surviving stands are mostly stunted and depauperate. Other brackish species have also been adversely effected, except forPhragmites australis which has increased. In contrast, the salt marsh speciesSpartina alterniflora has dramatically expanded, from <1% to 45% cover over the last decade. Locally, high marsh species have also become established, covering another 20% of the marsh. 相似文献
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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
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Warren B. White Kathryn A. Gloersen Francis Marsac Yves M. Tourre 《Journal of Oceanography》2004,60(3):531-541
Interannual coupled Rossby waves in the extratropical Indian Ocean propagate westward in covarying pycnocline depth, sea surface
temperature, and meridional surface wind anomalies from the west coast of Australia between 15°S and 35°S, taking 3–4 years
to transit the interior ocean to Madagascar. In the interior subtropical gyre, where the tuna longline catch (TLC) mainly
concerns two species (albacore and bigeye), these waves have been observed to affect year-to-year changes in catch, with wave
crests (troughs) in the main pycnocline associated with high (low) TLC anomalies. This suggested that tuna longline catch
is associated with the entrainment of nutrient-rich pycnocline water into the photic zone and a subsequent increase in primary
productivity there. Here, this hypothesis is examined within the context of SeaWiFS chlorophyll concentration (CC). We find
the situation the opposite of that expected, with wave crests (troughs) in the main pycnocline associated with low (high)
CC anomalies averaged over the photic zone. These results are shown to be consistent with a model relating the anomalous CC
tendency to upper-layer divergence in the wave, not unlike that relating surface slicks to upper-layer divergence in internal
gravity waves. Thus, the connection between interannual coupled Rossby waves and TLC in the interior subtropical gyre does
not appear to derive from wave-induced modulation of the pelagic food web.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献