Google Earth Engine（GEE）——利用MODIS 的叶面积指数影像掩膜dem批量下载

本次实验的目的就是为了用DEM去筛选和过滤全球叶面积指数，然后获取没5天一期的影像。

这里首先看一下影像的叶面积指数的波段信息：  

MCD15A3H.006 MODIS Leaf Area Index/FPAR 4-Day Global 500m

Resolution

500 meters

Bands Table

Name	Description	Min	Max	Wavelength	Scale
Fpar	FPAR absorbed by the green elements of a vegetation canopy	0	100	400-700nm	0.01
Lai	One-sided green leaf area per unit ground area in broadleaf canopies; one-half the total needle surface area per unit ground area in coniferous canopies	0	100		0.1

文中的DEM使用的

WWF HydroSHEDS Void-Filled DEM, 3 Arc-Seconds

Resolution

92.77 meters

Bands Table

Name	Description	Min*	Max*	Units
b1	Eleva