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Halpern, D.

Publications and source records attributed to Halpern, D..

At least 55 records · Page 3
All sourcesNASA NTRSDOE OSTI
NASA NTRS1995

An atlas of monthly mean distributions of SSMI surface wind speed, AVHRR/2 sea surface temperature, AMI surface wind velocity, TOPEX/POSEIDON sea surface height, and ECMWF surface wind velocity during 1993

The following monthly mean global distributions for 1993 are presented with a common color scale and geographical map: 10-m height wind speed estimated from the Special Sensor Microwave Imager (SSMI) on a United States (U.S.) Air Force Defense Meteorological Satellite Program (DMSP) spacecraft; sea surface temperature estimated from the Advanced Very High Resolution Radiometer (AVHRR/2) on a U.S. National Oceanic and Atmospheric Administration (NOAA) satellite; 10-m height wind speed and direction estimated from the Active Microwave Instrument (AMI) on the European Space Agency (ESA) European Remote Sensing (ERS-1) satellite; sea surface height estimated from the joint U.S.-France Topography Experiment (TOPEX)/POSEIDON spacecraft; and 10-m height wind speed and direction produced by the European Center for Medium-Range Weather Forecasting (ECMWF). Charts of annual mean, monthly mean, and sampling distributions are displayed.

Halpern, D.↗
NASA NTRS1994

ERS-1 Surface Wind Convergence Over the Arabian Sea During 1992-1993

The sea surface temperature over the Arabian Sea during the 1987-1993 monsoons will be described from Advanced Very High Resolution Radiometer measurements recorded on the National Oceanic and Atmospheric Administration polar-orbiting spacecrafts.

sea surface temperature monsoon atmospheric circul↗
NASA NTRS1994

Sea Surface Temperature and Wind-Generated Current Variations in the Arabian Sea During 1992 and 1993

Monthly mean wind-generated Ekman and Sverdup transports and the vertical transport into and out of the Ekman layer were computed from satellite scatterometer estimates of 10-m height wind speed components recorded from April 1992 to December 1993...This brief report describes a search for correspondence between variations of monthly mean SST and wind-driven currents in the Arabian Sea during April 1992 and December 1993.

north indian ocean clouds wind mixing heat advecti↗
NASA NTRS1994

ERS-1 scatterometer estimates of annual variations of Atlantic ITCZ and Pacific NECC

A 10 m height wind vector data set, named CMODFD, from ERS-1 Active Microwave Instrument (AMI) measurements, was compared with moored buoy wind observations. The CMODFD wind vectors compared favorably with moored buoy wind observations at about 60 sites. Satisfactory results were obtained from intercomparisons between CMODFD and moored buoy estimates of horizontal wind divergence and wind stress curl. The CMODFD positions of the Intertropical Convergence Zone (ITCZ) at 28 deg west were nearly equal to those determined from satellite images of clouds. The CMODFD data were employed to compute the Ekman vertical velocity in the region of the Pacific North Equatorial Countercurrent (NECC), and a correlative relation was found between the annual cycles and longitudinal variations of the NECC and Ekman vertical motion.

Halpern, D.↗
NASA NTRS1994

Remote sensing of seasonal and annual variation of equatorial new production: A model for global estimates

Sea-surface temperatures (SSTs) are strongly correlated with surface nitrate concentrations in coastal upwelling regions. Upwelling also occurs in the equatorial Pacific; correlations between temperature and nitrate concentration are strong. The University of Miami weekly averaged Advanced Very High Resolution Radiometer (AVHRR) SST data for October 1986 through June 1989 have been used to compute surface nitrate concentrations from 90 deg - 180 deg W and from 15 deg S - 15 deg N. The surface areas with nitrate above detection limits are combined with existing nitrate uptake data to give weekly estimates of equatorial new production.

Dugdale, R.↗
NASA NTRS1993

An atlas of monthly mean distributions of SSMI surface wind speed, ARGOS buoy drift, AVHRR/2 sea surface temperature, and ECMWF surface wind components during 1991

The following monthly mean global distributions for 1991 are presented with a common color scale and geographical map: 10-m height wind speed estimated from the Special Sensor Microwave Imager (SSMI) on a United States Air Force Defense Meteorological Satellite Program (DMSP) spacecraft; sea surface temperature estimated from the advanced very high resolution radiometer (AVHRR/2) on a U.S. National Oceanic and Atmospheric Administration (NOAA) spacecraft; Cartesian components of free-drifting buoys which are tracked by the ARGOS navigation system on NOAA satellites; and Cartesian components of the 10-m height wind vector computed by the European Center for Medium-Range Weather Forecasting (ECMWF). Charts of monthly mean value, sampling distribution, and standard deviation value are displayed. Annual mean distributions are displayed.

Halpern, D.↗
NASA NTRS1993

Evaluation of two January - June 1992 ERS-1 AMI wind vector data sets

A Jan. - Jun. 1992 10 m height wind vector field was computed with the CMOD2 model function. Freilich and Dunbar used ESA measurements of AMI (Active Microwave Instrument) sigma-naught to derive a refined model function and to produce an alternate Jan. - Jun. 1992 10 m height wind vector field, named FD data. The ESA and FD model functions and algorithms were substantially different. The FD wind vectors were in better agreement with the climatological mean wind field and with moored buoy wind measurements. The average correlation coefficients between monthly mean and daily averaged FD and moored buoy matchups of the Cartesian wind components were 0.84 and 0.74, respectively. The average root mean square differences between the monthly mean and daily averaged FD and moored buoy matchups of the Cartesian wind components were 1.25 and 3.0 m/s, respectively.

Halpern, D.↗
NASA NTRS1993

An atlas of monthly mean distributions of SSMI surface wind speed, ARGOS buoy drift, AVHRR/2 sea surface temperature, and ECMWF surface wind components during 1990

The following monthly mean global distributions for 1990 are proposed with a common color scale and geographical map: 10-m height wind speed estimated from the Special Sensor Microwave Imager (SSMI) on a United States (US) Air Force Defense Meteorological Satellite Program (DMSP) spacecraft; sea surface temperature estimated from the advanced very high resolution radiometer (AVHRR/2) on a U.S. National Oceanic and Atmospheric Administration (NOAA) spacecraft; Cartesian components of free drifting buoys which are tracked by the ARGOS navigation system on NOAA satellites; and Cartesian components on the 10-m height wind vector computed by the European Center for Medium-Range Weather Forecasting (ECMWF). Charts of monthly mean value, sampling distribution, and standard deviation values are displayed. Annual mean distributions are displayed.

Halpern, D.↗