WorldClim Global Mean Precipitation

WorldClim 2.1 provides downscaled estimates of climate variables as monthly means over the period of 1970-2000 based on interpolated station measurements. Here we provide analytical image services of precipitation for each month along with an annual mean. Each time step is accessible from a processing template. Time Extent: Monthly/Annual 1970-2000 Units: mm/month Cell Size: 2.5 minutes (~5 km) Source Type: Stretched Pixel Type: 16 Bit Integer Data Projection: GCS WGS84 Mosaic Projection: GCS WGS84 Extent: Global Source: WorldClim v2.1 Using Processing Templates to Access Time There are 13 processing templates applied to this service, each providing access to the 12 monthly and 1 annual mean precipitation layers. To apply these in ArcGIS Online, select the Image Display options on the layer. Then pull down the list of variables from the Renderer options. Click Apply and Close. In ArcGIS Pro, go into the Layer Properties. Select Processing Templates from the left-hand menu. From the Processing Template pull down menu, select the version to display. What can you do with this layer? This layer may be added to maps to visualize and quickly interrogate each pixel value. The pop-up provides a graph of the time series along with the calculated annual mean value. This layer can be used in analysis. For example, the layer may be added to ArcGIS Pro and an area count of precipitation may be produced for a feature dataset using the zonal statistics tool. Statistics may be compared with the statistics from month to month to show seasonal patterns. To calculate precipitation by land area, or any other analysis, be sure to use an equal area projection, such as Albers or Equal Earth. Source Data: The datasets behind this layer were extracted from GeoTIF files produced by WorldClim at 2.5 minutes resolution. The mean of the 12 GeoTIFs was calculated (annual), and the 13 rasters were converted to Cloud Optimized GeoTIFF format and added to a mosaic dataset. Citation: Fick, S.E. and R.J. Hijmans, 2017. WorldClim 2: new 1km spatial resolution climate surfaces for global land areas. International Journal of Climatology 37 (12): 4302-4315.WorldClim 2.1 基于插值站点观测数据，提供1970-2000年时段内气候变量的月均降尺度估算结果。本服务提供逐月降水与年平均降水的分析型影像服务，各时间步长均可通过处理模板获取。 时间范围：1970-2000年，逐月/逐年 单位：毫米/月（mm/month） 像元大小：2.5弧分（约5公里） 源数据类型：拉伸数据 像元类型：16位整数 数据投影：GCS WGS84 镶嵌投影：GCS WGS84 覆盖范围：全球 数据源：WorldClim v2.1 利用处理模板访问时间数据 本服务共应用13个处理模板，分别对应12个月度降水图层与1个年平均降水图层。在ArcGIS Online中使用时，请选中图层的「影像显示」选项，随后从「渲染器」下拉菜单中选择所需变量，点击「应用并关闭」即可。在ArcGIS Pro中，需进入「图层属性」面板，从左侧菜单选择「处理模板」，再从「处理模板」下拉菜单中选取对应版本以加载显示图层。 图层应用场景 该图层可添加至地图中，用于可视化展示并快速查询每个像元的数值。图层弹窗将展示时间序列图表与计算得到的年平均降水量。本图层可用于各类空间分析工作：例如，将其添加至ArcGIS Pro后，可通过分区统计工具（zonal statistics tool）针对要素数据集生成降水的面积统计结果；还可对比各月份的降水统计数据，以展示区域季节降水变化模式。若需按陆地面积计算降水量或开展其他空间分析，请务必使用等面积投影坐标系，例如阿尔伯斯投影（Albers）或等地球投影（Equal Earth）。 源数据说明 本图层依托的数据集源自WorldClim以2.5弧分分辨率生成的GeoTIFF文件。我们首先计算了12个月度GeoTIFF文件的平均值（即年平均降水），随后将这13个栅格转换为云优化GeoTIFF（Cloud Optimized GeoTIFF）格式，并添加至镶嵌数据集（mosaic dataset）中。 引用文献 Fick, S.E. 与 R.J. Hijmans, 2017年。《WorldClim 2：面向全球陆地区域的新型1公里空间分辨率气候表面》，刊载于《国际气候学杂志》（International Journal of Climatology）37(12): 4302-4315。