####
## make GISS TRP averages from zonal averages archived at GISS
###
### giss.trp - a list of 4 time series 
###
### see comparison to averages from gridded data in notes
#  CHECK ftp://data.giss.nasa.gov/pub/gistemp/GISS_Obs_analysis/ARCHIVE	



source("http://www.climateaudit.info/scripts/gridcell/read.binary.txt")
     

######################################################################
## ZON VERSIONS
######################################################################
numbertochar =function(x) if (x<10) paste ("0",x,sep="") else paste(x)

make.giss.trp=function(eff_month){ 
	#eff_month=paste( substr(Sys.Date(),1,4),"_",numbertochar( as.numeric(substr(Sys.Date(),6,7) )-1),sep="")

	giss.trp=list()	
##loti
	url=file.path("ftp://data.giss.nasa.gov/pub/gistemp/GISS_Obs_analysis/ARCHIVE",eff_month,"ZON/LOTI.zon.web")
	loti=read.zon.web(url);  tsp(loti)
		#[1] 1880.000 2009.833   12.000
	lat=as.numeric(dimnames(loti)[[2]]); temp= abs(lat)<20
	giss.trp[["loti"]]=ts(apply(loti[,temp],1,mean,na.rm=TRUE),start=1880,freq=12)

#sst
	url=file.path("ftp://data.giss.nasa.gov/pub/gistemp/GISS_Obs_analysis/ARCHIVE",eff_month,"ZON/SST.zon.web")
	x=read.zon.web(url)
	tsp(x)
		#[1] 1880.00 2009.25   12.00
	lat=as.numeric(dimnames(x)[[2]]); temp= abs(lat)<20
	giss.trp[["sst"]]=ts(apply(x[,temp],1,mean,na.rm=TRUE),start=1880,freq=12)


#land1200
	url=file.path("ftp://data.giss.nasa.gov/pub/gistemp/GISS_Obs_analysis/ARCHIVE",eff_month,"ZON/Ts.zon.web")
	x=read.zon.web(url) ;	tsp(x)
		#[1] 1880.00 2009.25   12.00
	lat=as.numeric(dimnames(x)[[2]]); temp= abs(lat)<20
	giss.trp[["land1200"]]=ts(apply(x[,temp],1,mean,na.rm=TRUE),start=1880,freq=12)

	
#land250
	url=file.path("ftp://data.giss.nasa.gov/pub/gistemp/GISS_Obs_analysis/ARCHIVE",eff_month,"ZON/Ts.zon250.web")
	x=read.zon.web(url) ;	tsp(x)
		#[1] 1880.00 2009.25   12.00
	lat=as.numeric(dimnames(x)[[2]]); temp= abs(lat)<20
	giss.trp[["land250"]]=ts(apply(x[,temp],1,mean,na.rm=TRUE),start=1880,freq=12)
	return(giss.trp)
}