Study of microwave emissivity characteristics of city

The spectrums of different land types are very important in the application of remote sensing, which can be used in surface classification, change detection, and so on. The microwave emissivity of these land types are the foundation of land parameters retrieval using passive microwave remote sensing. As one of the most important land types, city\´s contribution in a passive microwave pixel cannot be ignored. In this paper, some "pure" city microwave pixel was selected and RFI effect was evaluated using several indicators. Eliminating days of RFI contaminated, city microwave emissivity in lower frequencies was extracted from AMSR-E brightness temperature data in 2008. Then the characteristic of city emissivity was analyzed. Based on precipitation data, we are trying to find the factors to affect city emissivity. The results have shown that the RFI effect was little except some channels. City emissivity was different for different frequencies and polarizations. It increased with the frequency becoming higher. The emissivity fluctuated along with seasons. According to comparison with meteorological data, there was an obvious correlation between the city emissivity and rainfall in higher precipitation.