Papers by Raymond Schmitt
Journal of physical …, 2003
... The ring's relative vorticity in the depth range 372628 m used here was −0.... more ... The ring's relative vorticity in the depth range 372628 m used here was −0.05 to −0.15 times f. Background information and further analysis of these HRP data appear in Polzin et al. (1995), Kunze et al. ... Further background information and analysis can be found in Toole et al. ...
Science, 2005
Diapycnal mixing plays a significant role in the ocean's circulation and uptake of heat and c... more Diapycnal mixing plays a significant role in the ocean's circulation and uptake of heat and carbon dioxide, but has not been quantified in salt finger-driven thermohaline staircases. We recently performed a tracer release experiment in the western tropical Atlantic staircase at ~400 m depth. The observed dispersion implies an effective diapycnal diffusivity for tracer and salt of 0.8 to 0.9
Nature, 1900
The overturning circulation of the ocean plays an important role in modulating the Earth's c... more The overturning circulation of the ocean plays an important role in modulating the Earth's climate. But whereas the mechanisms for the vertical transport of water into the deep oceanÐdeep water formation at high latitudesÐand horizontal transport in ocean currents ...
Nature, 1900
The overturning circulation of the ocean plays an important role in modulating the Earth's c... more The overturning circulation of the ocean plays an important role in modulating the Earth's climate. But whereas the mechanisms for the vertical transport of water into the deep oceanÐdeep water formation at high latitudesÐand horizontal transport in ocean currents ...
More accurate seasonal predictions of seasonal rainfall are made possible using variations in sea... more More accurate seasonal predictions of seasonal rainfall are made possible using variations in sea surface salinity.
Eos, Transactions American Geophysical Union, 2006
The workshop participants agreed that highquality in situ winds are equally important to wave mea... more The workshop participants agreed that highquality in situ winds are equally important to wave measurements because the wind data are used to model the wave field.
1] Moored current observations in the southwestern East/ Japan Sea of 16.5 months duration clearl... more 1] Moored current observations in the southwestern East/ Japan Sea of 16.5 months duration clearly captured two episodes of downward phase propagation (upward energy propagation) of near-inertial waves (NIWs). Time series of temperature and velocity from the mooring and ancillary information indicate that the mooring was located near the center of an anticyclonic eddy during these events. Considering the typical vertical structure of quasipermanent eddy features in the region, the observed downward phase propagation appeared to occur within the seasonal thermocline and upper thermostad of the anticyclonic mesoscale eddy. Ray tracing simulation of NIW using the observed subinertial currents suggests that the upward energy propagation is caused by the reflection of the NIWs within the thermostad of the anticyclonic eddy, where the effect of the vertical shear of subinertial horizontal currents is larger than the buoyancy effect in controlling the propagation of NIWs. (2010), Observation of near-inertial wave reflections within the thermostad layer of an anticyclonic mesoscale eddy, Geophys.
Deep-sea Research Part Ii-topical Studies in Oceanography, 2004
The temporal,evolutionof,spatial pattern s of the colored water mass,associated with the discharg... more The temporal,evolutionof,spatial pattern s of the colored water mass,associated with the discharges of the Amazon and Orinoco Rivers between,1997 and,2002 was,examined,using concurrent,in situ and,satellite observations,in the regionboun ded,by 0 1N–241 Na n d7,01W–401W. Patches of low-salinity (� 32–34) surface waters,were,frequently observed,with Salinity Profiling Autonomous,LAgrangian Current Explorer (S-PALACE) floats as far as 2000 km,away from the mouths,of the Amazon,and Orinoco
Bulletin of The American Meteorological Society, 1996
Designs and implementation are proceeding for a Global Ocean Observing System (GOOS) and a Global... more Designs and implementation are proceeding for a Global Ocean Observing System (GOOS) and a Global Climate Observing System (GCOS). The initial design for the ocean component of the GCOS, which is also the climate module of the GOOS, was completed in 1995 by the Ocean Observing System Development Panel (OOSDP). This design for an ocean observing system for climate aims
OCEANS 2006, 2006
A new CTD has been designed for gliders and other AUVs. It uses a four-electrode conductivity cel... more A new CTD has been designed for gliders and other AUVs. It uses a four-electrode conductivity cell with internal temperature sensor to achieve excellent dynamic response and high spatial resolution. The design is rugged, has low drag and is resistant to fouling. No pump is required and the electronics are self-calibrating and free of thermal drifts.
Oceanography, 2010
... Authors. Gary Lagerloef NASA Aquarius Mission, Earth & Space Research, Seattle, W... more ... Authors. Gary Lagerloef NASA Aquarius Mission, Earth & Space Research, Seattle, WA, USA. Raymond Schmitt Woods Hole Oceanographic Institution (WHOI), Woods Hole, MA, USA. ... Nature 415:514517. [CrossRef]. Roemmich, D., and the Argo Steering Team. 2009. ...
Journal of Physical Oceanography, 2004
Observations of turbulence, internal waves, and subinertial flow were made over a steep, corrugat... more Observations of turbulence, internal waves, and subinertial flow were made over a steep, corrugated continental slope off Virginia during May-June 1998. At semidiurnal frequencies, a convergence of low-mode, onshore energy flux is approximately balanced by a divergence of high-wavenumber offshore energy flux. This conversion occurs in a region where the continental slope is nearly critical with respect to the semidiurnal tide. It is suggested that elevated near-bottom mixing (K ϳ 10 Ϫ3 m 2 s Ϫ1 ) observed offshore of the supercritical continental slope arises from the reflection of a remotely generated, low-mode, M 2 internal tide. Based on the observed turbulent kinetic energy dissipation rate ⑀, the high-wavenumber internal tide decays on time scales O(1 day). No evidence for internal lee wave generation by flow over the slope's corrugations or internal tide generation at the shelf break was found at this site.
Journal of Physical Oceanography, 1998
The effect of double-diffusive mixing on the general circulation is explored using the GFDL MOM2 ... more The effect of double-diffusive mixing on the general circulation is explored using the GFDL MOM2 model. The motivation for this comes from the known sensitivity of the thermohaline circulation to the vertical diffusivity and the earlier work of Gargett and Holloway, who studied the effects of a simple nonunity ratio between heat and salt diffusivities in a GCM. In this
Journal of Physical Oceanography, 2001
... Laurent and Schmitt 1999), observations from fjords suggest Γ 0.05 (Stigebrandt and Aure 1989... more ... Laurent and Schmitt 1999), observations from fjords suggest Γ 0.05 (Stigebrandt and Aure 1989). ... tracer concentration field as weighting in the spatial average, and is thus not representative of the larger diffusivities of (5–10) × 10 −4 m 2 s −1 that occur east of the tracer patch. ...
Journal of Physical Oceanography, 1999
Scaling analysis of the oceanic thermohaline circulation has been done under two types of surface... more Scaling analysis of the oceanic thermohaline circulation has been done under two types of surface boundary conditions: (i) Under ''relaxation'' conditions (sea surface temperature and salinity are relaxed to prescribed values), there is a two-thirds power law dependence of the meridional overturning (and the poleward heat transport) on the diapycnal diffusivity. For any given external forcing, there is only one equilibrium state for the thermohaline circulation. (ii) Under ''mixed'' boundary conditions (temperature is relaxed to prescribed values and a virtual salt flux condition is used for salinity), multiple equilibria become possible. For a given thermal forcing, the existence of multiple equilibria depends on the relative contributions of diapycnal diffusivity and the hydrologic forcing: for each diapycnal diffusivity K, there is a threshold freshwater flux E c ϭ CK 2/3 (C is a constant) below which three modes are possible with one stable thermal mode, one unstable thermal mode, and a stable haline mode and above which only one stable haline mode can exist.
Journal of Physical Oceanography, 1995
1] This article (1) reviews and clarifies the basic physics underpinning finescale parameterizati... more 1] This article (1) reviews and clarifies the basic physics underpinning finescale parameterizations of turbulent dissipation due to internal wave breaking and (2) provides advice on the implementation of the parameterizations in a way that is most consistent with the underlying physics, with due consideration given to common instrumental issues. Potential biases in the parameterization results are discussed in light of both and , and illustrated with examples in the literature. The value of finescale parameterizations for studies of the large-scale ocean circulation in the presence of common biases is assessed. We conclude that the parameterizations can contribute significantly to the resolution of large-scale circulation problems associated with plausible ranges in the rates of turbulent dissipation and diapycnal mixing spanning an order of magnitude or more.
Journal of Marine Research, 2010
The current capabilities of quantifying the oceanic freshwater cycle are shown based on new obser... more The current capabilities of quantifying the oceanic freshwater cycle are shown based on new observations from satellite data and re-analysis models for evaporation and precipitation over the ocean. For this purpose, we analyze the homogeneity and internal consistency of eight evaporation and seven precipitation products. Discontinuities are found around 1987 for all datasets, attributable to the launch of a microwave imaging satellite. Based on a review of comparisons with independent data and these analyses, the Global Precipitation Climatology Project (GPCP) and the Objectively Analyzed Ocean-Atmosphere Fluxes (OAFlux) evaporation product are combined with a state-of-the-art river discharge dataset to produce a new estimate of the global oceanic freshwater cycle for 1987-2006. The annual mean precipitation into the ocean averaged over 19 years is estimated at 12.2 ± 1.2 Sv, the evaporative loss at 13.0±1.3 Sv, and the total freshwater input from land at 1.25±0.1 Sv. The oceanic budget closes within the errors estimated for each data set with an imbalance of 0.5 ± 1.8 Sv. Based on this quantification, the global patterns of oceanic freshwater fluxes are described and a global mean is integrated to provide estimates of freshwater fluxes between basins. We find the Atlantic to be less evaporative and the Pacific less precipitative than previous in-situ estimates.
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Papers by Raymond Schmitt