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Simple expressions are obtained for the laws and moments of the probability distributions of averaged echo signals from meteorological targets at the output of a logarithmic radar receiver. Here, the distribution function is assumed to be represented in the form of an Edgeworth series.
The development and characteristics of a system for automatic transmission of meteorological data to U.S.S.R. weather stations are discussed. An algorithm to be used with computer storage facilities to avoid duplication of data is examined. A specific method for providing automated data transmission and reception is explained.
The author has identified the following significant results. Two meteorological data acquisition systems were built to support hydrometeorological programs related to flow forecasting. Data errors were detected in the stream level formation; these errors were caused by sensor difficulties.
Frequency distributions prepared from synoptic meteorological parameters at 300, 200, and 100 mb, associated with turbulent and non-turbulent areas encountered by the XB-70 airplane in the stratosphere (between 12 and 20 km), show that turbulence occurs more frequently than non-turbulence when the parameters exceed certain values. A procedure proposed for forecasting clear-air turbulence on the basis of the number of exceedances of limits of specified variables is verified for two flights of the XB-70 airplane. The procedure gives the geographical location of CAT regions, but further research is required before the altitude of CAT can be specified.
Meteorological satellites include experimental satellites operated by NASA and operational satellites operated by the National Oceanic and Atmospheric Administration (NOAA). The operational system currently provides pictures of the entire globe, temperature measurements throughout the world, and wind measurements in selected parts of the Atlantic and Pacific oceans. Aspects of vertical sounding are discussed along with questions of parameter extraction technique development, macroscale phenomena, the heat budget of the earth-atmosphere system and the climate, and studies of ocean surface and hydrology.
Theoretical models for the calculation of the radiative effects of atmospheric aerosols require the inference of such parameters as optical depth, the complex index of refraction and the equivalent size distribution. A polarimeter and a multispectral radiometer are used for local monitoring of aerosols via ground stations, or global monitoring via spacecraft occultation experiments. It is shown that measurements of optical depth at one wavelength as has been the custom, are insufficient to provide useful information for meteorological calculations, and new experiments and instruments must be devised to take advantage of new theoretical developments.
A symposium was conducted in which the following questions were discussed: (1) the evidence concerning possible relationships between solar activity and meteorological phenomena; (2) plausible physical mechanisms to explain these relationships; and (3) kinds of critical measurements needed to determine the nature of solar/meteorological relationships and/or the mechanisms to explain them, and which of these measurements can be accomplished best from space.
A set of numerical experiments was conducted to test the short-range sensitivity of a large atmospheric general circulation model to changes in solar constant and ozone amount. On the basis of the results of 12-day sets of integrations with very large variations in these parameters, it is concluded that realistic variations would produce insignificant meteorological effects. Any causal relationships between solar variability and weather, for time scales of two weeks or less, rely upon changes in parameters other than solar constant or ozone amounts, or upon mechanisms not yet incorporated in the model.
Procedures for forecasting clear air turbulence in the stratosphere over the western United States from rawinsonde data are described and results presented. Approaches taken to relate meteorological parameters to regions of turbulence and nonturbulence encountered by the XB-70 during 46 flights at altitudes between 12-20 km include: empirical probabilities, discriminant function analysis, and mountainwave theory. Results from these techniques were combined into a procedure to forecast regions of clear air turbulence with an accuracy of 70-80 percent. A computer program was developed to provide an objective forecast directly from the rawinsonde sounding data.
The accuracy of water vapor measurement required by modelers and forecasters at a number of scales of motion is discussed. Direct and indirect methods for operational use in obtaining atmospheric water vapor data are reviewed along with meteorological applications of water vapor data obtained by a space shuttle laboratory lidar system.
Crop-weather models developed for wheat from an assembled base of approximately 45 years of climatic records and historic wheat yield and production data at the stratum level are described. Utilization of meteorological data acquired by the NOAA satellites is discussed.
The author has identified the following significant results. This stage of the study has confirmed the initial supposition that LANDSAT data could be analyzed to provide useful data on cloud amount, and that useful light would be thrown thereby on the performance of the ground observer of this aspect of the state of the sky. This study, in comparison with previous studies of a similar nature using data from meteorological satellites, has benefited greatly from the much higher resolution data provided by LANDSAT. This has permitted consideration of not only the overall performance of the surface observer in estimating total cloud cover, but also his performance under different sky conditions.
In the last two decades, increasingly sophisticated deep space missions have placed correspondingly stringent requirements on navigational accuracy. As part of the effort to increase navigational accuracy, and hence the quality of radiometric data, much effort has been expended in an attempt to understand and compute the tropospheric effect on range (and hence range rate) data. The general approach adopted has been that of computing a zenith range refraction, and then mapping this refraction to any arbitrary elevation angle via an empirically derived function of elevation. The prediction of zenith range refraction derived from surface measurements of meteorological parameters is presented. Refractivity is separated into wet (water vapor pressure) and dry (atmospheric pressure) components. The integration of dry refractivity is shown to be exact. Attempts to integrate wet refractivity directly prove ineffective; however, several empirical models developed by the author and other researchers at JPL are discussed. The best current wet refraction model is here considered to be a separate day/night model, which is proportional to surface water vapor pressure and inversely proportional to surface temperature. Methods are suggested that might improve the accuracy of the wet range refraction model.
The electronics and temperature sensing units of the pulse-to-pulse rocketsonde are described. The sonde is designed for the 2 1/8-inch dart of the SUPER-LOKI meteorological rocket. In flight, the sonde descends by parachute from rocket apogees of about 75 kilometers. As the sonde descends, it transmits air temperature data back to ground radio receiving stations.
The data digitizing system takes pulsed signals from meteorological rocket sondes and radiosondes and converts the information (the time interval between pulses) into a digital form for magnetic recording and further processing by digital computer. The basic digitizer configuration contains a master sequencer that allows for data storage and release in an accumulator. Thus, the digitizer provides for convenient interfacing in real time monitoring.
All the meteorological data for the 19-hour period before the Titan 3 C (AF-777) launch from Kennedy Space Center at 1857 EST on December 13, 1973, are archived at the Marshall Space Flight Center. These data were collected in support of the NASA rocket exhaust effluent prediction and monitoring program. This data set is unique in that soundings were made with a high temporal resolution. All supporting data, such as synoptic charts and surface data, are also included. This is the first in a series of seven data reports.
Meteorological data for the 26-hour period prior to launch are recorded. Data were collected in support of the NASA rocket exhaust effluent prediction and monitoring program. Soundings were made approximately every 2 hours from T-14 hours to T-O; therefore, high temporal resolution is provided. All supporting data, such as synoptic charts and wind tower data, are also included.
All the meteorological data for the 32-hour period before the ATS-F launch from Kennedy Space Center at 0900 EDT on May 30, 1974, are archived at the Marshall Space Flight Center. These data were collected in support of the NASA rocket exhaust effluent prediction and monitoring program. This data set is unique in that soundings were made hourly from T-12 to T-0 hours, providing high temporal resolution. All supporting data, such as synoptic charts and surface data, are also included. This is the third in a series of seven data reports.