contin {ClimClass}

Continentality indices

Description

Calculates climate continentality / oceanicity according to several indices.

Usage

contin(clim_norm, latitude = NULL, elevation = NULL,
  Michalet_correction = FALSE, indices = 1:5)

Arguments

clim_norm

climatic normals

latitude

station latitude in degrees. Used in Gorczynski's and Conrad's classifications (indices 1 and 2). Default is NULL.

elevation

station elevation in m. Used in Gams' classification (index 3). Default is NULL.

Michalet_correction

logic: if TRUE, Michalet's correction is applied to index 3 (Gams). Default is FALSE.

indices

set of aridity indices to be listed. Default is all indices (1 to 5).

Details

clim_norm is a monthly data frame of climate normals, with column names: "P", "Tn", "Tx", "Tm" (precipitation, minimum, maximum and mean temperature, respectively). It can be the output of function climate.

indices' values are the following:

1: Gorczynski - K.G. (Gorczynski, L., 1920).

2: Conrad - K.C. (Conrad, 1946).

3: Gams - alpha. (Gams, H., 1932). For Michalet's correction: Michalet and Souchier, 1991.

4: Rivas-Martinez - Ic. (Rivas - Martinez, web page).

5: Amann - H. (Amann, 1929)

A reference for the continentality / oceanicity degree is given in the list object continental_ind_tables of data set Trent_climate.

If Michalet's correction is applied to Gams' hygric continentality index, the value of precipitation is proportionally diminished for elevations below 900 m a.s.l. See also Lebourgeoise, 2010.

Value

A single-line data frame with the desired continentality index(es).

Author(s)

Emanuele Eccel

References

Amann, J., 1929: L'hygrothermie du climat, facteur determinant la repartition des especes atlantiques. Revue Bryol., 56:126-133.

Conrad, V., 1946: Usual formulas of continentality and their limits of validity. Transactions, American Geophysical Union, Volume 27, Issue 5, p. 663-664.

Gams, H., 1932: Die klimatische Begrenzung von Pflanzenarealen und die Verteilung der hygrischen Kontinentalitaet in den Alpen. Zeitschr. Ges. Erdkunde, Berlin.

Gorczynski, L., 1920: Sur le calcul du degre de continentalisme et son application dans la climatologie. Geografiska Annaler 2, 324-331.

Lebourgeoise, F., 2010: Cours de bioclimatologie a l'usage des forestiers. Departement SIAFEE, UFR Forets, Arbres et Milieux Naturels. ENGREF, Nancy Cedex.

Michalet, R., and Souchier, B., 1991: Une approche synthetique biopedoclimatique del montagnes mediterraneennes: l'exemple du Maroc septemptrional. Thesis, Univ. J. Fourier, Grenoble, 273 pp.

Rivas-Martinez: http://www.globalbioclimatics.org/.

See Also

climate

Examples

data(Trent_climate)


# clima_81_10 is a list of data frames having climatic means of temperature and precipitation as 
# required by the aridity indices algorithms, each one referring to one station. 
# It can be the output of function climate.

# creates a data frame with all the continentality indices for all stations in clima_81_10

latit<-coord_elev$North
elev<-coord_elev$Elevation

contin_I<-NULL
for(i in 1:length(clima_81_10)) {
  contin_I[[i]]<-contin(clima_81_10[[i]], 
   latitude=latit[i], 
   elevation=elev[i], 
   Michalet_correction=TRUE)
}
names(contin_I)<-names(clima_81_10)