MODIS Vegetation Index (NDVI)

Measurements from NASA's Terra and Aqua polar satellites' MODIS instrument during the vegetation period (April 1st) (October 31st) of this year. The maximum vegetation index (NDVI) for 16 days is related to the ‘greenness’ and photosynthetic activity of the surface; the NDVI change map is made from the difference of two consecutive time steps, on which the change of the NDVI over 8 days can be tracked; the NDVI anomaly map shows the difference between the current vegetation index value and the long-term average, i.e. its deviation from the average.本数据集包含美国国家航空航天局（NASA）的Terra与Aqua极轨卫星搭载的中分辨率成像光谱仪（MODIS）在本年度植被生长期（4月1日至10月31日）期间获取的观测数据。其中，16天合成的归一化植被指数（NDVI）最大值与地表绿度及光合活性密切相关；NDVI变化图由两个连续时间步的差值生成，可用于追踪8天尺度的NDVI变化；NDVI距平图则展示了当前植被指数值与长期平均值的差值，即该指数相对于平均水平的偏差。