Google Earth Engine（GEE）——ERA5-数据计算逐年全球潜在蒸发量PET
通过ERA5-Land数据文件中关于如何汇总潜在蒸发（pet）数据集（将pet值米转换为毫米）
代码：
var geometry = /* color: #d63000 */ee.Geometry.Point([21.021809833554478, -9.078844651504086]);var aPoint = /* color: #d63000 */geometry;//影像筛选var era5hourly = ee.ImageCollection("ECMWF/ERA5_LAND/HOURLY").filter(ee.Filter.date('2000-01-01', '2020-12-31'));//添加色彩度var classColors = ['FFFFFF','E6E6E6','BEBEBE','969696','C4706E','C8B396','FFC775','FFFF54','91FF99','00FF00','40C738']//,'0D9605','05705E','003319','FF66FF','990099', '3333FF', '000099' ];//var TOTAL_MONTHLY_PET = "potential_evaporation";var metersToMillimiters = function( image ){ return ee.Image( image.select([TOTAL_MONTHLY_PET]).multiply(1000).multiply(-1) // 将m转化为mm
