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• 1. [Article] The fluxes of latent and sensible heat in the marine boundary layer

  Measurements of the fluctuations of humidity, temperature and velocity were made in the marine boundary layer. The humidity fluctuations were measured with a Lyman-alpha humidiometer. Temperature fluctuations ...

  Citation × Citation Citation Abstract Copy Title: The fluxes of latent and sensible heat in the marine boundary layer Author: Phelps, George Thomas Measurements of the fluctuations of humidity, temperature and velocity were made in the marine boundary layer. The humidity fluctuations were measured with a Lyman-alpha humidiometer. Temperature fluctuations were measured with a dry thermocouple and a platinum resistance thermometer. Velocity fluctuations were measured with a three component sonic anemometer. These measurements were made from the Floating Instrument Platform (FLIP) operated by the Scripps Institution of Oceanography near San Diego in February, 1969 and during the Barbados Oceanographic and Meteorological Expedition (BOMEX) in May 1969. The data were processed by digital techniques and the various spectra, cospectra and quadspectra between the velocities, humidity and temperature were obtained. Integrals of the cospectra were produced which allowed estimates of the fluxes of latent and sensible heat to be made. The normalized spectra of humidity fluctuations in San Diego and BOMEX have similar shapes. The normalized cospectra between vertical velocity and humidity in San Diego and BOMEX have similar shapes. Universal forms for the normalized humidity spectrum and the normalized cospectrum between vertical velocity and humidity may exist. The normalized spectra of the temperature fluctuations in San Diego and BOMEX have different shapes. The differences in shapes may be related to stronger radiation effects during BOMEX than in San Diego. The normalized cospectra between vertical velocity and temperature in San Diego and BOMEX also have different shapes. It is probable that a universal form does not exist for the normalized temperature spectrum or for the normalized cospectrum between vertical velocity and temperature. Directly measured values of the latent and sensible heat fluxes were used to test the validity of the bulk aerodynamic method of predicting the latent and sensible heat fluxes from the mean wind speed and mean air-sea humidity or temperature differences. The limited results from San Diego indicate that the sensible heat flux may probably be predicted from the mean wind speed and the mean air-sea temperature difference in temperate regions. The bulk aerodynamic method was not useful for predicting the sensible heat flux in BOMEX. The observed values for the sensible heat flux were much larger than would be predicted. The latent heat flux could be predicted from the mean wind speed and the mean air-sea absolute humidity difference with a probable error of less than 20%. The validity of the formula developed by Bowen (1926) for predicting the Bowen ratio (sensible heat flux/latent heat flux) was tested with directly measured values of the Bowen ratio. It was found that in San Diego the Bowen ratio could be predicted with a probable error of 15%. The Bowen ratio predicted for BOMEX was too low by a factor of two or more. The ability to predict the Bowen ratio from the ratio of the temperature fluctuations to the humidity fluctuations in the 0.05-0.1 Hz range was investigated. The method predicted the Bowen ratio with a probable error of 15% in San Diego and 20% in BOMEX. Title: The fluxes of latent and sensible heat in the marine boundary layer Author: Phelps, George Thomas Measurements of the fluctuations of humidity, temperature and velocity were made in the marine boundary layer. The humidity fluctuations were measured with a Lyman-alpha humidiometer. Temperature fluctuations were measured with a dry thermocouple and a platinum resistance thermometer. Velocity fluctuations were measured with a three component sonic anemometer. These measurements were made from the Floating Instrument Platform (FLIP) operated by the Scripps Institution of Oceanography near San Diego in February, 1969 and during the Barbados Oceanographic and Meteorological Expedition (BOMEX) in May 1969. The data were processed by digital techniques and the various spectra, cospectra and quadspectra between the velocities, humidity and temperature were obtained. Integrals of the cospectra were produced which allowed estimates of the fluxes of latent and sensible heat to be made. The normalized spectra of humidity fluctuations in San Diego and BOMEX have similar shapes. The normalized cospectra between vertical velocity and humidity in San Diego and BOMEX have similar shapes. Universal forms for the normalized humidity spectrum and the normalized cospectrum between vertical velocity and humidity may exist. The normalized spectra of the temperature fluctuations in San Diego and BOMEX have different shapes. The differences in shapes may be related to stronger radiation effects during BOMEX than in San Diego. The normalized cospectra between vertical velocity and temperature in San Diego and BOMEX also have different shapes. It is probable that a universal form does not exist for the normalized temperature spectrum or for the normalized cospectrum between vertical velocity and temperature. Directly measured values of the latent and sensible heat fluxes were used to test the validity of the bulk aerodynamic method of predicting the latent and sensible heat fluxes from the mean wind speed and mean air-sea humidity or temperature differences. The limited results from San Diego indicate that the sensible heat flux may probably be predicted from the mean wind speed and the mean air-sea temperature difference in temperate regions. The bulk aerodynamic method was not useful for predicting the sensible heat flux in BOMEX. The observed values for the sensible heat flux were much larger than would be predicted. The latent heat flux could be predicted from the mean wind speed and the mean air-sea absolute humidity difference with a probable error of less than 20%. The validity of the formula developed by Bowen (1926) for predicting the Bowen ratio (sensible heat flux/latent heat flux) was tested with directly measured values of the Bowen ratio. It was found that in San Diego the Bowen ratio could be predicted with a probable error of 15%. The Bowen ratio predicted for BOMEX was too low by a factor of two or more. The ability to predict the Bowen ratio from the ratio of the temperature fluctuations to the humidity fluctuations in the 0.05-0.1 Hz range was investigated. The method predicted the Bowen ratio with a probable error of 15% in San Diego and 20% in BOMEX. Close

• 2. [Article] Thermistor chain observations during MILDEX

  Citation × Citation Citation Abstract Copy Title: Thermistor chain observations during MILDEX Author: Levine, Murray D., Oregon State University. College of Oceanography, Simpkins, Jay, Gard, Steve R. Title: Thermistor chain observations during MILDEX Author: Levine, Murray D., Oregon State University. College of Oceanography, Simpkins, Jay, Gard, Steve R. Close