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• 2721. [Article] Microstructure Measurements from a Towed Undulating Platform

  MicroSoar, an undulating profiler capable of measuring turbulence parameters such as Thorpe scales and thermal dissipation rate while being towed at speeds of up to 4 m s⁻¹, offers the possibility of obtaining ...

  Citation × Citation Citation Abstract Copy Title: Microstructure Measurements from a Towed Undulating Platform Author: Erofeev, Anatoli Y., Ott, Michael W., Barth, John A. MicroSoar, an undulating profiler capable of measuring turbulence parameters such as Thorpe scales and thermal dissipation rate while being towed at speeds of up to 4 m s⁻¹, offers the possibility of obtaining a close-to-synoptic image of mixing over large spatial areas. In this paper, the method of calculating Thorpe scales from the high-frequency MicroSoar data is developed, and results from data taken off the coast of Oregon during the summer of 2001 are presented. Large Thorpe scales and elevated measurements of the thermal dissipation rate are shown to be associated with shear at the edge of the coastal jet. It is further shown that using MicroSoar data rather than Sea-Bird conductivity–temperature–depth data extends the range of measurable overturns to smaller scales, particularly in regions of low stratification. Title: Microstructure Measurements from a Towed Undulating Platform Author: Erofeev, Anatoli Y., Ott, Michael W., Barth, John A. MicroSoar, an undulating profiler capable of measuring turbulence parameters such as Thorpe scales and thermal dissipation rate while being towed at speeds of up to 4 m s⁻¹, offers the possibility of obtaining a close-to-synoptic image of mixing over large spatial areas. In this paper, the method of calculating Thorpe scales from the high-frequency MicroSoar data is developed, and results from data taken off the coast of Oregon during the summer of 2001 are presented. Large Thorpe scales and elevated measurements of the thermal dissipation rate are shown to be associated with shear at the edge of the coastal jet. It is further shown that using MicroSoar data rather than Sea-Bird conductivity–temperature–depth data extends the range of measurable overturns to smaller scales, particularly in regions of low stratification. Close

• 2722. [Article] Optical and hydrographic observations of the Cromwell Current between 92°00'W and the Galapagos Islands

  Copyrighted by American Geophysical Union.

  Citation × Citation Citation Abstract Copy Title: Optical and hydrographic observations of the Cromwell Current between 92°00'W and the Galapagos Islands Author: Zaneveld, J. Ronald, Plank, William S., Pak, Hasong Copyrighted by American Geophysical Union. Title: Optical and hydrographic observations of the Cromwell Current between 92°00'W and the Galapagos Islands Author: Zaneveld, J. Ronald, Plank, William S., Pak, Hasong Copyrighted by American Geophysical Union. Close

• 2723. [Article] Resistance of Grape Rootstocks to Crown Gall 1996-1997

  Crown gall can develop on grapevines wounded by freezing temperatures, mechanical damage or grafting. Increased demand for grape varieties grafted to phylloxera resistant rootstocks has led to increased ...

  Citation × Citation Citation Abstract Copy Title: Resistance of Grape Rootstocks to Crown Gall 1996-1997 Author: Ferguson, Kathleen, Schindler, Clara, Miller, Marilyn L., Tooley, Katie, Moore, Larry W. Crown gall can develop on grapevines wounded by freezing temperatures, mechanical damage or grafting. Increased demand for grape varieties grafted to phylloxera resistant rootstocks has led to increased incidence of crown gall at graft unions. Therefore a search for plant material that is resistant to crown gall has been undertaken. Previous studies on resistance have produced confusing and in some cases contradictory results, probably due to the difference in methods and agrobacterial strains used in each investigation (5, 11). Title: Resistance of Grape Rootstocks to Crown Gall 1996-1997 Author: Ferguson, Kathleen, Schindler, Clara, Miller, Marilyn L., Tooley, Katie, Moore, Larry W. Crown gall can develop on grapevines wounded by freezing temperatures, mechanical damage or grafting. Increased demand for grape varieties grafted to phylloxera resistant rootstocks has led to increased incidence of crown gall at graft unions. Therefore a search for plant material that is resistant to crown gall has been undertaken. Previous studies on resistance have produced confusing and in some cases contradictory results, probably due to the difference in methods and agrobacterial strains used in each investigation (5, 11). Close

• 2724. [Article] Vine Damage, Recovery Methods, and Future Strategies After the 1989 Freeze

  The late winter cold front in early February 1989 brought significant snowfall and low temperatures to all of Oregon viticulture and caused considerable vine damage in the northeastern and in some western ...

  Citation × Citation Citation Abstract Copy Title: Vine Damage, Recovery Methods, and Future Strategies After the 1989 Freeze Author: Lombard, Porter The late winter cold front in early February 1989 brought significant snowfall and low temperatures to all of Oregon viticulture and caused considerable vine damage in the northeastern and in some western valleys of Oregon. The lateness of this winter freeze was unusual since most winter damage in the Pacific Northwest typically occurs from an early winter freeze before vines and trees have hardened. The 1989 minimums ranged from -13°F in Boardman to -1°F in The Dalles from February 2-10, while lows in the western valleys were from -1°F in Salem to 8°F in McMinnville (see Table 1). Lowest minimums occurred in Boardman and Milton-Freewater in the northeast and in Salem, Eugene, Roseburg, and Cave Junction in the western valleys, where vine damage was most severe. Title: Vine Damage, Recovery Methods, and Future Strategies After the 1989 Freeze Author: Lombard, Porter The late winter cold front in early February 1989 brought significant snowfall and low temperatures to all of Oregon viticulture and caused considerable vine damage in the northeastern and in some western valleys of Oregon. The lateness of this winter freeze was unusual since most winter damage in the Pacific Northwest typically occurs from an early winter freeze before vines and trees have hardened. The 1989 minimums ranged from -13°F in Boardman to -1°F in The Dalles from February 2-10, while lows in the western valleys were from -1°F in Salem to 8°F in McMinnville (see Table 1). Lowest minimums occurred in Boardman and Milton-Freewater in the northeast and in Salem, Eugene, Roseburg, and Cave Junction in the western valleys, where vine damage was most severe. Close

• 2725. [Article] Evaluation of the Effects of Yeast Strains on the Composition, Aroma, and Flavor on Several Winegrape Cultivars 1992-1993

  Yeast strains used in wine production are known to differ in some fermentation characteristics, including rates of fermentation, alcohol tolerance, degree of foaming, temperature tolerances, volatile acid production, ...

  Citation × Citation Citation Abstract Copy Title: Evaluation of the Effects of Yeast Strains on the Composition, Aroma, and Flavor on Several Winegrape Cultivars 1992-1993 Author: Watson, Barney, Dumont, Ann, McDaniel, Mina Yeast strains used in wine production are known to differ in some fermentation characteristics, including rates of fermentation, alcohol tolerance, degree of foaming, temperature tolerances, volatile acid production, and hydrogen sulfide production. There may also be significant sensory differences in aroma and flavor in wines fermented with different yeast strains. The objective of this research is to evaluate the effects of different yeast strains of Saccharomyces cerevisiae on wine composition, aroma, and flavor of Pinot noir, Chardonnay, and Riesling, the primary winegrape varieties grown in Oregon. The yeast strains to be studied were selected from commercially available freeze-dried concentrates, many of which are used commercially in Oregon. Title: Evaluation of the Effects of Yeast Strains on the Composition, Aroma, and Flavor on Several Winegrape Cultivars 1992-1993 Author: Watson, Barney, Dumont, Ann, McDaniel, Mina Yeast strains used in wine production are known to differ in some fermentation characteristics, including rates of fermentation, alcohol tolerance, degree of foaming, temperature tolerances, volatile acid production, and hydrogen sulfide production. There may also be significant sensory differences in aroma and flavor in wines fermented with different yeast strains. The objective of this research is to evaluate the effects of different yeast strains of Saccharomyces cerevisiae on wine composition, aroma, and flavor of Pinot noir, Chardonnay, and Riesling, the primary winegrape varieties grown in Oregon. The yeast strains to be studied were selected from commercially available freeze-dried concentrates, many of which are used commercially in Oregon. Close

• 2726. [Article] Heat and mass balances of the South Atlantic Ocean calculated from a numerical model

  copyrighted by American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: Heat and mass balances of the South Atlantic Ocean calculated from a numerical model Author: Matano, Ricardo P., Philander, S. George H. copyrighted by American Geophysical Union Title: Heat and mass balances of the South Atlantic Ocean calculated from a numerical model Author: Matano, Ricardo P., Philander, S. George H. copyrighted by American Geophysical Union Close

• 2727. [Article] A simplified three-dimensional model for Martian climate studies

  We described a simplified physics approach to generating time-varying global wind and temperature fields suitable for conducting transport studies on Mars. The goal is to develop a computationally fast ...

  Citation × Citation Citation Abstract Copy Title: A simplified three-dimensional model for Martian climate studies Author: Vong, Richard E., Haberle, Robert M., Houben, Howard, Barnes, Jeffrey R. We described a simplified physics approach to generating time-varying global wind and temperature fields suitable for conducting transport studies on Mars. The goal is to develop a computationally fast algorithm that will enable long-term simulations of the planet’s climate system. Thus we use a three-dimensional log-pressure global spectral model forced with a simplified physics package based on Newtonian cooling and Rayleigh friction. We examine the model’s performance at northern winter solstice for clear and dusty conditions and find that the simulated mean meridional circulation and transient eddies compare well with a more sophisticated general circulation model by tuning a single parameter: the thermal damping time. Best results are obtained for a thermal damping time of 2 days for clear conditions and 1 day for dusty conditions. Title: A simplified three-dimensional model for Martian climate studies Author: Vong, Richard E., Haberle, Robert M., Houben, Howard, Barnes, Jeffrey R. We described a simplified physics approach to generating time-varying global wind and temperature fields suitable for conducting transport studies on Mars. The goal is to develop a computationally fast algorithm that will enable long-term simulations of the planet’s climate system. Thus we use a three-dimensional log-pressure global spectral model forced with a simplified physics package based on Newtonian cooling and Rayleigh friction. We examine the model’s performance at northern winter solstice for clear and dusty conditions and find that the simulated mean meridional circulation and transient eddies compare well with a more sophisticated general circulation model by tuning a single parameter: the thermal damping time. Best results are obtained for a thermal damping time of 2 days for clear conditions and 1 day for dusty conditions. Close

• 2728. [Article] An Effect of the Thermobaric Nonlinearity of the Equation of State: A Mechanism for Sustaining Solitary Rossby Waves

  The thermobaric nonlinearity in the equation of state for seawater density—namely, the dependence of thermal expansibility on pressure—coupled with spatial variation of the oceanic temperature–salinity ...

  Citation × Citation Citation Abstract Copy Title: An Effect of the Thermobaric Nonlinearity of the Equation of State: A Mechanism for Sustaining Solitary Rossby Waves Author: de Szoeke, Roland A. The thermobaric nonlinearity in the equation of state for seawater density—namely, the dependence of thermal expansibility on pressure—coupled with spatial variation of the oceanic temperature–salinity (θ–s) relation generates a nonlinear behavior in the buoyant force that can counter the linear dispersion of baroclinic Rossby waves and produce solitary waves. A Korteweg–deVries equation is derived in which the coefficient of the nonlinear term depends on the thermobaric parameter and the spatial gradient of the anomaly of the θ–s relation. Quantitative estimates can be made of the magnitude of the effect in terms of these parameters. For example, given first-baroclinic-mode spatial variations of order 0.1 psu (1000 km)⁻¹ or 0.7°C (1000 km)⁻¹, from a θ–s relation with a density ratio of 2, a solitary Rossby wave of maximum vertical displacement of approximately 100 m and horizontal scale of approximately 30 baroclinic Rossby radii of deformation can be generated. Title: An Effect of the Thermobaric Nonlinearity of the Equation of State: A Mechanism for Sustaining Solitary Rossby Waves Author: de Szoeke, Roland A. The thermobaric nonlinearity in the equation of state for seawater density—namely, the dependence of thermal expansibility on pressure—coupled with spatial variation of the oceanic temperature–salinity (θ–s) relation generates a nonlinear behavior in the buoyant force that can counter the linear dispersion of baroclinic Rossby waves and produce solitary waves. A Korteweg–deVries equation is derived in which the coefficient of the nonlinear term depends on the thermobaric parameter and the spatial gradient of the anomaly of the θ–s relation. Quantitative estimates can be made of the magnitude of the effect in terms of these parameters. For example, given first-baroclinic-mode spatial variations of order 0.1 psu (1000 km)⁻¹ or 0.7°C (1000 km)⁻¹, from a θ–s relation with a density ratio of 2, a solitary Rossby wave of maximum vertical displacement of approximately 100 m and horizontal scale of approximately 30 baroclinic Rossby radii of deformation can be generated. Close

• 2729. [Article] An instrument system for measurement of evapotranspiration by the eddy correlation method

  A fast response meteorological instrument system for measuring parameters used in calculating evapotranspiration above a forest stand is described. Comprised of Gill-type propeller anemometers, Brady-array ...

  Citation × Citation Citation Abstract Copy Title: An instrument system for measurement of evapotranspiration by the eddy correlation method Author: U.S. International Biological Program. Coniferous Forest Biome, Belt, George H., King, Jack, University of Washington, Baily, Everett Minnich, 1938- A fast response meteorological instrument system for measuring parameters used in calculating evapotranspiration above a forest stand is described. Comprised of Gill-type propeller anemometers, Brady-array humidity sensors, thermistor air-temperature sensors and a Metro-Data digital tape recorder, the system was designed to measure eddy fluctuations in the range from one to 0.005 cycles per second. Details of the shop-built signal conditioning circuitry for the Brady-array are presented along with a discussion of apparatus and techniques employed to calibrate the sensors as a part of the instrument system. Problems with electrical noise and condensation within instrument packages which occurred during field trials are also discussed. Title: An instrument system for measurement of evapotranspiration by the eddy correlation method Author: U.S. International Biological Program. Coniferous Forest Biome, Belt, George H., King, Jack, University of Washington, Baily, Everett Minnich, 1938- A fast response meteorological instrument system for measuring parameters used in calculating evapotranspiration above a forest stand is described. Comprised of Gill-type propeller anemometers, Brady-array humidity sensors, thermistor air-temperature sensors and a Metro-Data digital tape recorder, the system was designed to measure eddy fluctuations in the range from one to 0.005 cycles per second. Details of the shop-built signal conditioning circuitry for the Brady-array are presented along with a discussion of apparatus and techniques employed to calibrate the sensors as a part of the instrument system. Problems with electrical noise and condensation within instrument packages which occurred during field trials are also discussed. Close

• 2730. [Article] Relationship of Moist Convection to Boundary-Layer Properties: Application to a Semiarid Region

  A simple analytical expression is developed to relate the energy required to initiate moist convection to boundary-layer properties. This expression and exploratory regression are applied to data from ...

  Citation × Citation Citation Abstract Copy Title: Relationship of Moist Convection to Boundary-Layer Properties: Application to a Semiarid Region Author: Mahrt, L., Pierce, Donald A simple analytical expression is developed to relate the energy required to initiate moist convection to boundary-layer properties. This expression and exploratory regression are applied to data from the National Hail Research Experiment to discriminate between environments leading to cumulus congestus and well-developed hail-producing thunderstorms in northeast Colorado. In this semiarid region, the parcel stability below the lifted condensation level is greater in environments leading to hail-producing thunderstorms compared to environments producing only cumulus congestus, as has been found in previous studies. As a result, boundary-layer properties have a multiplicity of contrasting influences on the severity of moist convection. For example, convection severity in this region generally increases with increasing low-level moisture. However, for a fixed mixed-layer depth and temperature, convection severity increases with decreasing low-level moisture because such a decrease increases the parcel stability below the condensation level Title: Relationship of Moist Convection to Boundary-Layer Properties: Application to a Semiarid Region Author: Mahrt, L., Pierce, Donald A simple analytical expression is developed to relate the energy required to initiate moist convection to boundary-layer properties. This expression and exploratory regression are applied to data from the National Hail Research Experiment to discriminate between environments leading to cumulus congestus and well-developed hail-producing thunderstorms in northeast Colorado. In this semiarid region, the parcel stability below the lifted condensation level is greater in environments leading to hail-producing thunderstorms compared to environments producing only cumulus congestus, as has been found in previous studies. As a result, boundary-layer properties have a multiplicity of contrasting influences on the severity of moist convection. For example, convection severity in this region generally increases with increasing low-level moisture. However, for a fixed mixed-layer depth and temperature, convection severity increases with decreasing low-level moisture because such a decrease increases the parcel stability below the condensation level Close