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--- aerocom:faq-reformatting [2014-12-19 09:43:46]
michaels created
+++ aerocom:faq-reformatting [2017-03-23 12:07:07]
michaels
@@ Line 1: / Line 1: @@
 ====== Reformatting files to AeroCom/HTAP standards ======
+The AeroCom standard is described in the section "submitting to the AeroCom database".\\
+https://wiki.met.no/aerocom/data_submission
+Below simple nco commands are listed which can be of help to reformat.
+A public set of format correction tools is under development and can be accessed here:\\
+https://github.com/metno/aerocom-data-correction-tools
+Format can be checked with a CF checker, eg:\\
+http://cf-checker.met.no/upload
 ===== How to remind me of nco commands =====
@@ Line 5: / Line 16: @@
 ===== How to rename variables =====
-ncrename -v oldvar,newvar in.nc
+	 ncrename -v oldvar,newvar in.nc
 ===== How to add an attribute =====
-ncatted -a experiment,newvar,a,c in.nc
+	 ncatted -a experiment,newvar,a,c,"BASE" in.nc
 ===== Split files per variable  =====
 https://code.zmaw.de/projects/cdo/embedded/1.6.4/cdo.html#x1-880002.2.6
+===== rename dimension =====
+	 ncrename -O -d LATITUDE,y       temp.nc
+===== sums =====
+	 ncap2 -O -s "LOAD_BCPOM[time,x,y]=LOAD_BC+LOAD_POM" ${file} ${file}
+===== compute vertical integrals =====
+	 rm dummy.nc
+	 ncwa -O -v AERH2O3D_AER   -a z -y ttl     ${file} dummy.nc
+	 ncrename -O -v AERH2O3D_AER,AERH2O_AER       dummy.nc
+	 ncks -F -A -v AERH2O_AER dummy.nc ${file}
+===== add variable to file =====
+	 ncks -F -A -v AIRE temp.nc ${file}
+===== make the time dimension unlimited =====
+	 ncecat -O $file $file
+	 ncpdq -O -a time,record $file $file
+	 ncwa -O -a record $file $file
+	 ncpdq -O -a time,y,x $file $file
+===== turn z =====
+	 ncpdq -O -a -z $file $file
+===== create yearly mean file =====
+from 12 months in one file
+	 orgfile=MM_${model}.an${an}.mALLYEAR_an.nc
+	 ncwa -F -O -a time ${file} ${orgfile}
+===== calculate yearly average =====
+ fom 12 files each containing 1 month
+	 ncra -F -O  modis_2000??.nc ${yearfile}
+===== create record dimension =====
+	 ncecat -O $file $file
+===== delete useless record dimension =====
+	 ncwa -O -a record $file $file
+===== turn lat to have right order =====
+ with interpolated files
+	 ncpdq -O -a "-y" $file $file
+===== Shift left and right hemispheres =====
+	 file1=aire_1.nc
+	 ncks -h -F -O -d x,1,180 $file $file1
+	 file2=aire_2.nc
+	 ncks -h -F -O -d x,181,360 $file $file2
+	 ncap -O -s "x[x]=x-360" $file2 $file2
+	 ncrcat -O $file2 $file1 $file
+	\rm  $file1 $file2
+===== Similar reorder of longitude =====
+	ncecat -O $file $file
+	ncpdq -O -a x,record $file $file
+	ncwa -O -a record $file $file
+	file1=DD_${model}.an${AN}.mALLYEAR_1.nc
+	ncks -F -O -d x,1,180 $file $file1
+	file2=DD_${model}.an${AN}.mALLYEAR_2.nc
+	ncks -F -O -d x,181,360 $file $file2
+	ncap -O -s "x[x]=x-360" $file2 $file2
+	ncrcat -O $file2 $file1 $file
+	\rm  $file1 $file2
+	ncpdq -O -a time,y,x $file $file
+===== missing values =====
+	ncatted -O -a missing_value,$var,o,f,0 ${file}
+	ncatted -O -a missing_value,$var,o,f,-9999 ${file}
+actually better use attribute _FillValue (see http://nco.sourceforge.net)
+===== compute monthly mean files =====
+    for IMTH in ${MTH[*]} ; do
+	file=DD_${model}.an${AN}.m${IMTH}.nc
+	filemean=DD_${model}.an${AN}.m${IMTH}_m.nc
+	ncra -F -O  ${file} ${filemean}
+    done
+===== delete attributes =====
+    ncatted -O -a ,,d,, interdummy.nc
+    ncatted -h -a ,global,d,, interdummy.nc
+    ncatted -h -a missing_value,,d,, interdummy.nc