Contributing Area - Multiple Flow Direction (Partial) derived from 1" SRTM DEM-H

CA_MFD_PARTIAL is contributing area in m2 computed using multiple flow directions on hillslopes and ANUDEM-derived flow directions in channels. The contributing area was computed on 1 degree tiles with 200 cell (about 5 km) overlaps so the areas in channels do not account for catchments beyond that size (hence the use of PARTIAL in the name). The primary purpose of this product was to calculate topographic wetness index (TWI; Gallant and Wilson, 2000) for which full contributing areas in channels are not necessary. Do not use this product to represent contributing areas of catchments larger than 5 km across.

The CA_MFD_PARTIAL product was derived from the Hydrologically enforced Digital Elevation Model (DEM-H; ANZCW0703014615), which was derived from the 1 arc-second resolution SRTM data acquired by NASA in February 2000.

This data is available in tiled format at 1 arc-second and 3 arc-second resolution.

The 3 arc-second resolution product was generated from the 1 arc-second CA_MFD (partial) product and masked by the 3” water and ocean mask datasets.

CA_MFD_PARTIAL是利用山坡上的多流向法（multiple flow directions）和河道中ANUDEM衍生的流向计算得到的、以平方米（m²）为单位的汇水面积。汇水面积的计算基于1度分块，各分块间存在200个像元（约5公里）的重叠区域，因此河道中的汇水面积未包含超出该尺度的流域（这也是名称中使用"PARTIAL"的原因）。该产品的主要用途是计算地形湿度指数（topographic wetness index, TWI；Gallant和Wilson，2000），而计算该指数无需河道中的完整汇水面积。请勿使用本产品表示跨度超过5公里的流域的汇水面积。

CA_MFD_PARTIAL产品源自水文增强数字高程模型（Hydrologically enforced Digital Elevation Model, DEM-H；ANZCW0703014615），而该模型又源自美国国家航空航天局（NASA）于2000年2月获取的1角秒分辨率SRTM数据。

该数据以分块格式提供，分辨率包括1角秒和3角秒。

3角秒分辨率的产品由1角秒分辨率的CA_MFD（partial）产品生成，并通过3角秒水体与海洋掩膜数据集进行掩膜处理。