#!/bin/sh
# Create Long Island Sound topography grid at 3 arc second resolution
# add 1 m to DEM data approximate conversion from 
# mean sea level to mean low water  so it doesn't overwrite the
# bathy values
#
# note:  zcat below is the GZIP version that allows one to 
#        zcat GZIPped files as well as UNIX compress

zcat dem/*.xyz.gz  | \
awk '{printf "%12.6f %12.6f %8.2f\n",$1,$2,$3+1}' > dem.xyz
zcat lis_ngdc.dat.gz lis_appgeo.dat.gz lis_mgrim.dat.gz dem.xyz | \
blockmedian -R/-74/-71.2/40.5/41.5/ -I0.05m -V > li.median
cat li.median | surface -R/-74/-71.2/40.5/41.5/ -I0.05m -Gli.grd -T0.35 -C0.2 -V
grd2xyz li.grd | gzip -c > li.xyz.gz