A Method For Fengyun Satellite Land Surface Temperature Retrieval And Its Availability For Frost Monitoring

Though seventeen kinds of surface temperature inversion algorithms with highaccuracy already exist, most of these were only suitable for satellites such asModerate-resolution Imaging Spectroradiometer (MODIS) or Advanced SpaceborneThermal Emission and Reflection Radiometer (ASTER). Medium Resolution SpectralImager (MERSI) in Fengyun no.3(FY-3) with single infrared channel has been exploredfor surface temperature inversion, but algorithms suitable for Fengyun satellites werestill lack. Especially algorithms applicable to Fengyun sensors with two or multipleinfrared channels such as Visible and Infra Red Radiometer sensor (VIRR) were scarce.According to the above problems, on the use of the second generation of polarorbiting meteorological satellite Fengyun no.3data and analysis of remote sensing frostmonitoring factors, Fengyun no.3channel characteristics and inversion algorithms exist,Qin Zhihao surface temperature inversion algorithm had been applied to Fengyun no.3VIRR surface temperature inversion. The inversion temperatures had been used for frostmonitoring in two orchards in Ningxia autonomous region. The effectiveness of remotesensing factor achieved in this paper was proved good enough for frost monitoring bywell reflection of temperatures changes before and after frost days and capture of lowtemperatures on the days.The main research contents were listed as follows.1. The frost disasters dates occurred from2002to2010were collected and collated.The meteorological frost monitoring factors had been chosen from many meteorologicalelements.2. On the studies of influences of different time and space scale on relationshipbetween surface temperatures and air temperatures, MODIS land surface temperatureproducts MOD11and MYD11the day after the minimum temperatures obtained wereextracted in1×1pixel window to explore the relationships between surfacetemperatures and minimum temperatures. The relationships between them were goodwith correlation coefficient around0.95. Thus, surface temperatures can be used as thefrost monitoring factors in remote sensing.3. The methods of three important parameters of temperature inversion were explored in this paper. The data from fourth and fifth channel were used for brightnesstemperatures calculation. The data from second and tenth channel were used forinversion of atmospheric water vapor. Relationships between atmospheric water vaporand atmospheric transmittance were simulated by MODTRAN4and vegetation indexeswere used for surface emissivity calculation.4. Based on data format, spectral response function and characteristics of theinfrared channel of Visible and Infra Red Radiometer sensor of the second generation ofpolar orbiting meteorological satellite Fengyun no.3and analysis of17kinds of splitwindow surface temperature inversion algorithms, Qin Zhihao surface temperatureinversion algorithm was chose for land surface temperature inversion of Fengyun no.3.Elimination the influence of the clouds, correlation coefficient of temperatures ofFengyun no.3and MODIS land surface temperatures reached0.82.