FY-3A/MERSI与MODIS的温度植被干旱指数反演及对比分析

为了探讨近年来被广泛使用的MODIS数据以及我国的FY-3A/MERSI数据对同一地区同一时刻的旱情所得的温度植被指数的差异以及可比性，选择我国四川省旱灾频发的攀西地区为研究区，分别反演MODIS-TVDI和MERSI-TVDI，并探讨两者监测结果的特点以及可比性。结果发现:（1）MERSI数据的干湿边线性拟合系数要高于MODIS数据。（2）MODIS-TVDI与MERSI-TVDI的差值变化范围在-0.12到0.23，差值均值为0.11，MODIS数据的监测结果比MERSI数据的监测结果略大。（3）MODIS-TVDI与MERSI-TVDI在各类地物的反演结果上都具有较高的一致性，其中林地R²最高为0.944。（4）MODIS-TVDI、MERSI-TVDI与当前月份降雨量存在显著负相关，其线性相关系数分别为-0.83，-0.91，两者干旱监测结果是可信的。

Tempeture Vegetation Drought Index(TVDI) Retrieve and Comparison between FY-3A/MERSI and MODIS

In order to present the difference and comparability between Tempeture Vegetation Drought Index (TVDI) retrieved by FY-3A/MERSI and MODIS in Panxi region, TVDI abstracted from MERSI and MODIS are calculated and compared. The following conclusions are be drawn: (1) the fitting coefficient of the dry-wet edge of MERSI is much higher; (2) the difference of MODIS-TVDI and MERSI-TVDI is from -0.12 to 0.23 and the mean of the difference is 0.11, the MODIS-TVDI is slightly higher than MERSI-TVDI; (3) each inversion result of various kinds of ground objects showed a better linear consistency, the maximum R² was forest land, which reached to 0.944; (4) MODIS-TVDI and MERSI-TVDI are significantly negatively correlated with the rainfall of the current month and the R² were -0.83, -0.91, respectively.The drought monitoring results are credible.