Difference between revisions of "Evapotranspiration"

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Step 2. Calculate the annual heat index (I):
Step 2. Calculate the annual heat index (I):
<math>I=\sum_{i=1}^{12}i</math>
<math>I=\sum_{i=1}^{12}i</math>
Step 3. Calculate an uncorrected Potential Evapotranspiration (PET<sub>uncorrected</sub>):
<math>PET_{uncorrected}=1.6\cdot \left ( \frac{10\cdot T}{I} \right )^{\alpha }</math>
where: α = 6.75 x 10<sup>-7</sup>''I<sup>3</sup>'' - 7.71 x 10<sup>-5</sup>''I<sup>2</sup>''+ 0.0179''I'' + 0.49

Revision as of 16:21, 8 January 2018

Thornthwaite Mather method[edit]

Step 1. Calculate the monthly heat index (i): where: T = mean monthly temperature.


Step 2. Calculate the annual heat index (I):

Step 3. Calculate an uncorrected Potential Evapotranspiration (PETuncorrected):

where: α = 6.75 x 10-7I3 - 7.71 x 10-5I2+ 0.0179I + 0.49