NCL Regional Temperature Anomolies

Data
HadCRUT 4
Surface Temperature Anomalies (C with respect to 1961-1990)

Choose a region

Getting my regions in a reusable, correctly projected, and regridded  was more difficult than I thought it would be.
Publicly available global region based netCDF files are not common
In the end, I used a shape file to create a netCDF with a single time dimension, and  integer layer of region ids at each 1 degree

Australia

Just going with continents at this stage and Australia is the country I was born.

Start with a single day.
; read only desired  time 1970
 x  = fin->temperature_anomaly(1440,:,:)

 xr = where(region.eq.2,x,x@_FillValue)

 print(avg(xr))

Then time series for a single year. Oct 2012 to Sept 2013 

; Time Series average for Australia 2013
 x1=fin->temperature_anomaly(1953:1964,:,:)
 rconform = conform(x1, region, (/1,2/))
 xr1 =mask(x1, rconform, 2)

 xa1 = dim_avg_n(xr1,(/1 , 2/))
 t1 = ispan(0,12,1)

 wks   = gsn_open_wks ("x11","xy")                ; open workstation
 res                  = True                     ; plot mods desired
 res@tiMainString     = "Average Australian Temperature Anomaly 2013" ;

Result similar to BOM 

Then annual time series for a decade or so

 yStart = 1990
 yEnd = 2013
 tStart  = (yStart - T_OFFSET ) * 12;
 tEnd = (yEnd - T_OFFSET) * 12 + 11
 x2=fin->temperature_anomaly(tStart:tEnd,:,:)
    
 rconform2 = conform(x2, region, (/1,2/))
 xr2 =mask(x2, rconform2, 2)
 copy_VarCoords(x2, xr2) ; need dim metadata retained for clim functions
 xa2 = dim_avg_n(xr2,(/1 , 2/))
  xannual = month_to_annual(xa2, 1)  ;Annual Average Temperautre             

  printVarSummary(xannual)  

 wks   = gsn_open_wks ("ps","xy")                ; open workstation
 res                  = True                     ; plot mods desired
 res@tiMainString     = "Annual Mean  Australian Temperature  1990-2013" ;
 res@tiYAxisString = "Anomalies" ; y-axis label      

 res@gsnYRefLine           = 0.              ; reference line   
 res@gsnXYBarChart         = True            ; create bar chart 
 res@gsnAboveYRefLineColor = "red"           ; above ref line fill red
 res@gsnBelowYRefLineColor = "blue"          ; below ref line fill blue

res@tiXAxisString = "Year"

 plot  = gsn_csm_xy (wks,ispan(yStart,yEnd,1),xannual,res) ; create plot  

Then summer time series for a decade

 ; Summer Time Average Temperature anomaly for 2000's
 yStart = 2000
 yEnd = 2013
 tStart  = (yStart - T_OFFSET ) * 12 ;
 tEnd = (yEnd - T_OFFSET) * 12 + 11
 x3=fin->temperature_anomaly(tStart:tEnd,:,:)
    
 rconform3 = conform(x3, region, (/1,2/)) ;Create Mask grid with time dim of data
 xr3 =mask(x3, rconform3, 2) ; mask out data not in region 2 , Australia
 copy_VarCoords(x3, xr3) ; need dim metadata retained for clim functions

 xseasonal = month_to_seasonN(xr3, (/ "DJF"/))  ; Seasonal Average Temperautre       
 printVarSummary(xseasonal)  

 xa3 = dim_avg_n(xseasonal,(/2 , 3/)) ; Average across  long and lat dimension
                                ; average across region as all other values masked 
 copy_VarCoords_2(xseasonal,xa3)
 printVarSummary(xa3)

 print(xa3)

 wks   = gsn_open_wks ("x11","xy")                ; open workstation
 res                  = True                     ; plot mods desired
 res@tiMainString     = "Summer Mean  Australian Temperature  1990-2013" ;
 res@tiYAxisString = "Anomalies" ; y-axis label      

 res@gsnYRefLine           = 0.              ; reference line   
 res@gsnXYBarChart         = True            ; create bar chart 
 res@gsnAboveYRefLineColor = "red"           ; above ref line fill red
 res@gsnBelowYRefLineColor = "blue"          ; below ref line fill blue

res@tiXAxisString = "Year"

 plot  = gsn_csm_xy (wks,ispan(yStart,yEnd,1),xa3(0,:),res) ; create plot 

Happy with this time to move on