# Climate

## Selyaninov's Hydrothermic Coefficient. April .

Download GIS-layers### Authors:

A.N. Afonin, K.L. Lipiyainen, Y.S. Li, V.Y. Tsepelev### Compilation date:

15.10.2005.### Scale:

10 km/pix### Map's precision:

The map contains the values of Selyaninov's Hydrothermic Coefficient for patches of the earth's surface with the area of 10 x 10 km. This layer is derivative and has been compiled by way of calculation using layers of mean monthly air temperatures and atmospheric precipitation.### Projection:

"Albers Equal Area for the USSR":ref. system : Albers Equal Area Conic for Russia

projection : Albers Equal Area Conic

datum : Pulkovo 1942 (S42)

delta WGS84 : 28 -130 -95

ellipsoid : Krasovsky

major s-ax : 6378245.000

minor s-ax : 6356863.019

origin long : 100

origin lat : 0

origin X : 0

origin Y : 0

scale fac : na

units : m

parameters : 2

stand ln 1 : 44

stand ln 2 : 68

### Main content:

A bitmapped map containing the mean values of Selyaninov's Hydrothermic Coefficient (SHC). SHC describes moistening conditions. Unlike precipitation measurements, SHC takes into account temperature-related vaporability. SHC is calculated on the basis of the following formula: the amount of precipitation for the period during which air temperatures are above + 5.C is divided by the sum of average daily temperatures for the same period reduced to its tenth part (Selyaninov, 1937). On the whole, SHQ values over 1 are typical of normal or excessive moistening, while those less than 1 are typical of moistening insufficient for basic cultivated crops.### Classifier precision:

Calculated to the nearest whole numnber.### Map compilation procedure:

This layer is derivative and has been compiled by way of calculation using layers of mean monthly air temperatures and atmospheric precipitation (Afonin et al., 2006). The calculation was done with the Delphi program. Calculation formula: SHQ = Pcp05/ (SumT05/10)Where = Pcp05 - the amount of precipitation for the period during which air temperatures were above + 5.C; SumT05 - the sum of average daily temperatures for the same period. "-100" = the pixels outside the Atlas.

### Data sources:

Afonon, A.N., Lipiyaynen, K.L., Tsepelev, V.Y. 2006. Maps of Mean Average Annual Air Temperature and Atmospheric Precipitation. In: Afonin, А.N., Grinn, S.L., Dzyubenko, N.I., Frolov, А.N. Interactive Atlas of Useable Plants, Their Pests and Ecological Factors in Russia and Neighboring Countries. [Internet-version 1.0]. St. Petersburg, Russia. St. Petersburg State University, Faculty of Geography. http://www.agroatlas.ruSelyaninov, G.T. 1937. Methods of Climate Description to Agricultural Purposes. In: World Climate and Agriculture Handbook, Leningrad - Moscow.