sdsm {seas}R Documentation

Read and write from SDSM

Description

Reads and writes the data format used in SDSMs ‘DAT’ and ‘OUT’ extensions.

Usage

# reading
read.sdsm(file, start = 1961, end = 2000, year.length = 366)
read.sdsm(file)

# writing
write.sdsm(dat, var, start, end, file)
write.sdsm(dat, var)

Arguments

file name of ‘DAT’ or ‘OUT’ file
dat data.frame of variables to be written
start starting year
end ending year
var name of variable to be written from dat
year.length maximum allowable year length; this is usually 366 for measured data, 365 for CCCma model data and 360 for Hadley model data

Details

This function readings and writes climate data with the Statistical Downscaling Model, or SDSM. The model uses ‘DAT’ extensions for input data, such as daily observations of mean temperature, and ‘OUT’ extensions for modeled output.

Since the files used by SDSM do not have any meta-data, read.sdsm attempts to interpret this from the filename, otherwise this needs to be specified. The following table shows how this decision is made:
grep start end year.length
Cal 1961 2000 366
Cur 1961 2000 365
2020 2010 2039 365
2050 2040 2069 365
2050 2070 2099 365

Value

read.sdsm returns a data.frame of the measured variables. The variables are named V1...Vn, for n ensembles.

Author(s)

M.W. Toews

References

Wilby, R.L., Dawson, C.W. and Barrow, E.M. 2002, ‘SDSM - a decision support tool for the assessment of regional climate change impacts’, Environmental Modelling Software, 77, 473–471.

SDSM can be downloaded free-of-charge for Windows platforms from http://www-staff.lboro.ac.uk/~cocwd/SDSM/

CGCM1 and HADCM3 model data for SDSM can be downloaded from the Canadian Climate Impacts and Scenarios website: http://www.cics.uvic.ca/scenarios/sdsm/select.cgi

See Also

read.msc

Examples

## Not run: 
# reading
gf50 <- read.sdsm("GF_2050s_precip.OUT")
gf50.ss <- seas.sum(gf50,var=paste("V",1:20,sep=""),name="Grand Forks")
# analysis
image(gf50.ss,var="V1")
image(gf50.ss,var="V2")
image(gf50.ss,var="V3")

# writing
data(mscdata)
hj <- mksub(mscdata,id=2100630)
write.sdsm(hj,"precip",1961,2000,"HJ_Obs_prcp.DAT")
## End(Not run)

[Package seas version 0.2-1 Index]