Mean annual transpiration from the plant canopy for the present day scenario

\n\nMean annual (00) and monthly (01a|12) transpiration (mm) from the plant canopy\nfor the period 1980-1999.Interpretation:Canopy transpiration is far more\nspatially variable than potential evaporation, reflecting the effects of water\nlimitation in most areas of the continent. Both the annual mean and seasonal\npattern broadly resemble the corresponding patterns for rainfall. Canopy\ntranspiration maps have more acontrasta (relative variation) than the total\nevaporation or rainfall maps because transpiration is a small component of\ntotal evaporation in areas of low plant cover (the remainder being soil\nevaporation).The partitioning between soil evaporation and canopy\ntranspiration in the model is determined by leaf area index.Notes: These are\nmodel-based estimates from the BiosEquil model. Results are given for the\naBASEa (pre-1788) and aAGRICa (present day) conditions. The aAGRICa case\nincludes current agricultural inputs of water from\nirrigation.EvapCanopy.00.Agric, EvapCanopy.01.Agric a| EvapCanopy.12.Agric a\nMean annual and monthly canopy transpiration (mm) in the aAGRICa (present day)\nscenarioEvapCanopy.00.Base, EvapCanopy.01.Base a| EvapCanopy.12.Base a Mean\nannual and monthly canopy transpiration (mm) in the aBASEa (pre-1788)\nscenarioData is in geographics and GDA94.\n\nSee [further metadata](http://data.daff.gov.au/anrdl/metadata_files/pa_ctab_r9cl\n__01411a01.xml) for more detail.\n\n

1980年至1999年间，植物冠层蒸腾（canopy transpiration）的年平均（标识00）与逐月（标识01a|12）总量，单位为毫米。
### 解读：
冠层蒸腾的空间变异性远高于潜在蒸发量（potential evaporation），这反映了澳大利亚大陆多数区域受水分限制的影响。年平均值与季节变化模式均与降雨量的对应模式大体相似。冠层蒸腾图的相对变异（对比度）高于总蒸发量或降雨量图，原因在于在植物覆盖度较低的区域，蒸腾仅为总蒸发量的较小组成部分，其余部分为土壤蒸发。模型中土壤蒸发与冠层蒸腾的分配比例由叶面积指数（leaf area index）决定。
### 备注：
本数据集为基于BiosEquil模型的模拟估算结果。结果包含「aBASE」（1788年以前）与「aAGRIC」（当代）两种情景，其中「aAGRIC」情景涵盖当前农业灌溉取水的相关场景。
- EvapCanopy.00.Agric、EvapCanopy.01.Agric 至 EvapCanopy.12.Agric：对应「aAGRIC」（当代）情景下的年平均与逐月冠层蒸腾量，单位为毫米
- EvapCanopy.00.Base、EvapCanopy.01.Base 至 EvapCanopy.12.Base：对应「aBASE」（1788年以前）情景下的年平均与逐月冠层蒸腾量，单位为毫米
本数据集采用地理坐标系及GDA94（Geocentric Datum of Australia 1994）。
更多详细元数据请参阅[相关元数据文档](http://data.daff.gov.au/anrdl/metadata_files/pa_ctab_r9cl__01411a01.xml)。