interpolating sea ice concentration onto NAA grid

1) Download the ice concentration data from  http://nsidc.org/data/G10010

2) I am only interested in satellite data from 1979 to 2013, so extract data only for that time period:
ncea -F -d time,1549,1968 G10010_SIBT1850_v1.1.nc G10010_SIBT1850_v1.1_HH1979_2013.nc

3) Convert the data into NAA grid using SOSIE:
../bin/sosie.x -f namelist.ice2naa

4) Compute the monthly climatology (ref: http://tldp.org/HOWTO/Bash-Prog-Intro-HOWTO-7.html):
for k in `seq 1 12`; do `echo "ncra -F -d time_counter,$k,420,12 icecon_G10010_SIBT1850_v1.1-naa_icecon.nc4 $k.nc"`; done

5) Concatenate the climatology for each month into a single file (ref: http://research.jisao.washington.edu/data_sets/nco/#example8):
ncrcat -h [0123456789].nc 1[012].nc icecon_mon_clim.nc