Derived Weather Parameters - Soil Parameters

Soil Moisture Index (SMI) | Soil Moisture Deficit (SMD) | Soil Water Content | Soil Type

Soil Parameters

Soil Moisture Index (SMI)

The soil moisture index indicates the wetness of the soil. This index is computed using the permanent wilting point and the field capacity, which both depend on the geographical location (soil type). The index is 0 if the permanent wilting point is reached and 1 at field capacity. Note that the index can exceed 1 after rainfall events. The soil moisture index is available for 4 depth levels.
soil_moisture_index_<depth>:idx
Available depths: -5cm, -15cm, -50cm, -150cm
Depth Identifier Soil Layer
-5cm 0 - 7 cm
-15cm 7 - 28 cm
-50cm 28 - 100 cm
-150cm 100 - 289 cm
Examples

Soil Moisture Deficit (SMD)

This parameter computes the difference between the actual water content of the soil and the possible water content that the soil can hold in mm. The amount of water that can be hold is called field capacity. The calculation of the SMD is mainly based on soil water information in several depths as well as other meteorological parameters. The SMD is a useful tool in order to assess prevailing soil conditions like droughts. The SMD also depends on the soil type.
soil_moisture_deficit:mm
Examples

Soil Water Content

This parameter provides the volume of water for 4 soil layers. The soil water content depends on the soil type, soil depth and the groundwater level.
volumetric_soil_water_<depth>:m3m3
Available depths: -5cm, -15cm, -50cm, -150cm
Depth Identifier Soil Layer
-5cm 0 - 7 cm
-15cm 7 - 28 cm
-50cm 28 - 100 cm
-150cm 100 - 289 cm
Examples

Soil Type

This parameter provides the soil type for any location on the globe. The index takes values from 0 to 7, where each number indicates an individual soil type.
soil_type:idx
Soil Type Description
0 Ocean/Lake
1 Coarse
2 Medium
3 Medium Fine
4 Fine
5 Very Fine
6 Organic
7 Tropical Organic
Examples
  1. Wikipedia Page of Wind Chill: http://en.wikipedia.org/wiki/Wind_chill
  2. WMO Weather Code Standard: https://www.nodc.noaa.gov/archive/arc0021/0002199/1.1/data/0-data/HTML/WMO-CODE/WMO4677.HTM