# [CLOUDS]-Section

## Purpose

Normally ENVI-met is run for cloud-free sky conditions as in this situation the spatial and temporal differences can be observed best. However, there may be a demand to run ENVI-met also with the assumption of an existing cloud cover.

To include clouds in your simulation, use the [CLOUDS]-Section:

00: [CLOUDS]__________________________________Cloud cover
01: Fraction of LOW clouds (x/8)                0
02: Fraction of MEDIUM clouds (x/8)             0
03: Fraction of HIGH clouds (x/8)               0

## What do the lines mean?

#### 01-03: Fraction of Cloud Cover in LOW, MEDIUM and HIGH Layer (Default 0/8)

Give the fraction of clouds in x/8 for each layer. The sum fraction of all layers cannot be higher than 8/8!

Warning: Different to the direct shortwave radiation, the diffuse component is not attenuated by vegetation in the recent version. Introducing clouds into the model can therefore actually lead to higher temperatures compared to free-sky conditions if a lot of vegetation is present in the model area as the energy distribution is shifted towards the diffuse component!