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# Date: 2014-01-20
# Author: Oliver Elison Timm
# Purpose: get the latest global mean temperatures (annual mean) HADCRUT4 
# from the official source (annual mean northern and southern hemispheres)
# http://www.metoffice.gov.uk/hadobs/hadcrut4/data/current/download.html
# and create a plot of the global mean temperatures
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### clean up memory
rm(list=ls())

### download the data first and store
### it in your data directory as hadcrut4ann.txt
buffer<-read.table("data/hadcrut4ann.txt")


### HERE IS SOMETHING USEFUL: 
### the default column names (if R doesn't find anything useful in the
### data file in the first line that looks like label names it uses
### V1 V2 V3 etc as names)
### we create labels for the columns in the data
###
labels<-make.names(c("time","median","conf.lower1",
                     "conf.upper1","conf.lower2","conf.upper2",
                     "conf.lower3","conf.upper3","conf.lower4",
                     "conf.upper4","conf.lower5","conf.upper5"))

attr(buffer,which="names")<-labels
### here we check the new names
print(names(buffer))

### here our first plot: time series of the global mean annual mean temperature anomalies

plot(buffer$time,buffer$median,typ='l',col=2,lwd=3,xlab='year [C.E.]',ylab='temp. [deg C]',main='HADCRUT4')
dev.copy2pdf(file="figures/hadcrut4ann.pdf")