##FUNCTION
  #utility function to allocate site (lat, long) to geographical class in Briffa   

##A. GEOGRAPHIC REGIONS
  #utility function to allocate site (lat, long) to geographical class in Briffa   
    briffa.class<-function(lat,long){
	briffa.class<-NA
	briffa.class[geog(lat,35,52,long,-35,30)]<-"SEUR"	
	briffa.class[geog(lat,52,89,long,-35,30)|geog(lat,55,89,long,30,60)]<-"NEUR"
	briffa.class[geog(lat,55,89,long,60,130)]<-"NSIB"
	briffa.class[geog(lat,55,89,long,130,170)]<-"ESIB"
	briffa.class[geog(lat,40,55,long,30,120)]<-"CAS"
	briffa.class[geog(lat,25,40,long,60,120)]<-"TIBP" #21
	briffa.class[geog(lat,50,89,long,-180,-120)|geog(lat,50,60,long,-120,-115)|geog(lat,50,55,long,-115,-105)]<-"NWNA" #30
	briffa.class[geog(lat,30,50,long,-130,-100)]<-"WNA"#48
	briffa.class[geog(lat,60,89,long,-120,-115)|geog(lat,55,89,long,-115,-105)|geog(lat,50,89,long,-105,-100)|geog(lat,40,89,long,-100,-50)]<-"ECCA"#45
	briffa.class
	}

   geog<-function(lat,S,N,long,W,E) {
	geog<-(lat>S)&(lat<N)&(long>W)&(long<E)&!is.na(lat)&!is.na(lat)
	geog}

  #make list of regions	
   briffa.region=rep(list(NA),9);names(briffa.region)= c("NEUR", "SEUR", "NSIB", "ESIB", "CAS",  "TIBP", "WNA",  "NWNA", "ECCA")
	lat= seq(37.5,47.5,5); long=seq(-12.5,27.5,5);	briffa.region$SEUR=c(outer(lat,long,jones))

 	lat= seq(52.5,72.5,5); long=seq(-12.5,27.5,5);	briffa.region$NEUR=c(outer(lat,long,jones))
 	lat= seq(57.5,72.5,5); long=seq(32.5,57.5,5);briffa.region$NEUR=c(briffa.region$NEUR,c(outer(lat,long,jones)))

	lat= seq(57.5,72.5,5); long=seq(62.5,127.5,5);	briffa.region$NSIB=c(outer(lat,long,jones))

 	lat= seq(57.5,72.5,5); long=seq(132.5,177.5,5);	briffa.region$ESIB=c(outer(lat,long,jones))
	lat= seq(57.5,72.5,5); long=seq(-177.5,-172.5,5);briffa.region$ESIB=c(briffa.region$ESIB,c(outer(lat,long,jones)))

 	lat= seq(42.5,52.5,5); long=seq(32.5,112.5,5);	briffa.region$CAS=c(outer(lat,long,jones))

 	lat= seq(27.5,37.5,5); long=seq(62.5,112.5,5);	briffa.region$TIBP=c(outer(lat,long,jones))
 
	lat= seq(52.5,72.5,5); long=seq(-167.5,-122.5,5);briffa.region$NWNA=c(outer(lat,long,jones))
	lat= seq(52.5,57.5,5); long=seq(-117.5,-117.5,5);briffa.region$NWNA=c(briffa.region$NWNA,c(outer(lat,long,jones)))
	lat= seq(52.5,52.5,5); long=seq(-112.5,-107.5,5);briffa.region$NWNA=c(briffa.region$NWNA,c(outer(lat,long,jones)))

	lat= seq(32.5,47.5,5); long=seq(-127.5,-102.5,5);briffa.region$WNA=c(outer(lat,long,jones))
 
 	lat= seq(62.5,72.5,5); long=seq(-117.5,-117.5,5); briffa.region$ECCA=c(outer(lat,long,jones))
 	lat= seq(57.5,72.5,5); long=seq(-112.5,-107.5,5);briffa.region$ECCA=c(briffa.region$ECCA,c(outer(lat,long,jones)))
	lat= seq(52.5,72.5,5); long=seq(-102.5,-100.5,5);briffa.region$ECCA=c(briffa.region$ECCA,c(outer(lat,long,jones)))
	lat= seq(42.5,72.5,5); long=seq(-97.5,-52.5,5);briffa.region$ECCA=c(briffa.region$ECCA,c(outer(lat,long,jones)))