Region code and Data

Hi, I just started using GMT,
So, I want to plot the data to some region but, the data location I have is in the distance (km)
Can I change the code and plot it using those data or do I have to change the data into long lat

#xyz2grd hrs20141125.dat -G20141125.grd -R131.9813/132.9062/33.69584/34.43750 -I0.012332/0.00824067
region=131.9813/132.9062/33.69584/34.43750
output=20141125.ps
grdfile=20141125.grd
cptfile=tstgmt.cpt

pscoast -R131.9813/132.9062/33.69584/34.43750 -JM15c -Ba10f5 -Df -W5 -P -G200 -K > $output
grdview $grdfile -JM15.0c -R$region -C$cptfile -P -K -O -T >> $output
psxy hrs_be20141125.dat -R$region -JM15c -Ba1 -Sc0.13 -C$cptfile -K -O >> $output
psxy hrs_bw20141125.dat -R$region -JM15c -Ba1 -Sc0.13 -C$cptfile -K -O >> $output
psxy hrs_bk20141125.dat -R$region -JM15c -Ba1 -Sc0.13 -C$cptfile -K -O >> $output
psxy hrs_bs20141125.dat -R$region -JM15c -Ba1 -Sc0.13 -C$cptfile -K -O >> $output
pstext -J -R -B -K -O << EOF >> $output
132.03 34.4 28 0 0 TL 20141125
EOF
psscale -D7.5/-1/10/0.5h -O -C$cptfile -B1p -Q >> $output
convert 20141125.ps 20141125.gif

I hope someone can help.
Thank you

If you are starting with GMT, please consider using modern mode instead of old GMT 4 syntax. Things would then look simpler, e.g.,

gmt plot hrs_b[ewks]20141125.dat -Sc0.13 -C$cptfile

Unclear what your geographic region is w.r.t your distances so hard to suggest a solution.