Modified Methods of Estimating Space-Time Spectra from Polar-Orbiting Satellite Data
نویسنده
چکیده
A simplification is made of the nonorthogonal Fourier transform method (Salby, 1982) for estimating space-time spectra from uneven twice-daily data sampled by a polar-orbiting satellite. The modified method transforms frequency only by the use of the Galilean transformation, while Salby's method transforms both frequency and wavenumber. Space-time spectra are obtained from the time-Fourier transform with respect to the Doppler-shifted frequency as viewed from the satellite. They wavenumber-frequency aliasing characteristics are examined and the computer code is exemplified.
منابع مشابه
Modified Methods of Estimating Space-Time Spectra from Polar-orbiting Satellite Data Part II : The Wavenumber Transform Method
In order to estimate space-time spectra correctly from uneven twice-daily data sampled by a polar-orbiting satellite, the wavenumber transform method (Hayashi, 1980) is modified by the use of a nonorthogonal Fourier inversion. The space-time spectra are obtained from the time-Fourier coefficients of the space-Fourier transforms of the asynoptic field with respect to its frequency-shifted wavenu...
متن کاملSpace - Time Spectral Analysis and its Applications to Atmospheric Waves
Space-time spectral analysis methods and their applications to large-scale atmospheric waves are reviewed. Space-time spectral analysis resolves transient waves into eastward and westward moving components and is mathematically analogous to rotary spectral analysis which resolves twodimensional velocity vectors into clockwise and anticlockwise components. Space-time spectral analysis can also r...
متن کاملNpoess and Goes-r—building a “system of Systems”
1. INTRODUCTION Late this decade, the National Polar-orbiting Operational Environmental Satellite System (NPOESS) Integrated Program Office (IPO) will initiate a new generation of passive electro-optical multispectral imagers and hyperspectral sounders to operate in three complementary orbit planes. NPOESS will replace the now-venerable civil Polar-orbiting Operational Environmental Satellite (...
متن کاملCombined Use of Polar Orbiting and Geo-stationary Satellites to Improve Time Interpolation in Dynamic Crop Models for Food Security Assessment
Use of satellite data in crop growth monitoring could provide great value for regional food security assessments. By using the difference between remotely sensed crop canopy temperature and the corresponding ambient temperature at the time of the satellite overpass the daily actual rate of transpiration can be inferred. This relationship allows adjustment of the actual rate of assimilation and ...
متن کاملMapping High-Resolution Incident Photosynthetically Active Radiation over Land from Polar-Orbiting and Geo stationary Satellite Data
Incident photosynthetically active radiation (PAR) is required by almost all terrestrial ecosystem models and many other applications. The current PAR products that are developed for climate studies have much coarser spatial resolution and higher temporal resolution and are not suitable for land applications. This article reviews stateof-the-art methods for mapping land spatial-resolution incid...
متن کامل