SMAP Satellite Temperature Product Research And Analysis In China Region

At present, countries all over the world are paying more and more attention to the natural environment research. The temperature as one of the most important climatic factors, its data acquisition and analysis has become more important. Detecting t he temperature in ground stations has the advantages of real-time and high accuracy, but ground site has mal distribution and for many special places the ground site detection traffic is inconvenience. Therefore, the meteorological satellite for its wide range and continuous temperature detection can make up the shortage. SMAP satellite is a satellite launched in 2015 in the United States to explore soil moisture and it can generate the global soil moisture map by 2 or 3 days. Because the SMAP satellite is relatively new, the research on the air temperature products is less yet. This paper selects the SMAP satellite level 4 temperature products as the research object and use the data to match more than 200 C hina international ground exchange station temperature data. After that, the paper analyze and evaluate the results from three aspects of the whole C hina region, special terrain and different temperature zone, then draws the following conclusion:(1) The paper uses SMAP satellite temperature data to match more than 200 C hina international ground exchange station temperature data for three month. As a result, the correlation coefficient is 0.94 and the average temperature of the difference between the star and ground site is-0.86 K. The star error in most of China is less than ±5K, except that the star temperature deviation of the northwest and southwest individual area is greater than ± 10 K. From January to March, with the increase of time and temperature, the overall correlation coefficients trends to turn smaller, and the deviation between the star and ground site trends to become smal er too.(2) The plain, plateau and basin are selected as examples in different special terrain regions. With the increase of the terrain complexity, the matching results of the plain and plateau to the basin showed a worse trend. In the same special terrain, the more complex the terrain is, the worse the matching results will be.(3) For different temperature zones, its discrete degree have tended to become good from north to South. With the increase of temperature or decrease of latitude, the temperature difference between the star and the ground site is decreased. Due to its very high elevation and the surrounding terrain, the matching results of the Q inghai Tibet Plateau are relatively poor and the temperature difference between the stars and ground site is relatively low.