Just reporting how I finally calculated the global_rad map. >r.slope.aspect elev=srtm3_for_global_rad slope=slope_for_global_rad aspect=aspect_for_global_rad format=degrees
>i.latitude input=srtm3_for_global_rad latitude=latitude_for_global_rad >i.longitude input=srtm3_for_global_rad longitude=longitude_for_global_rad >r.horizon elevin=srtm3_for_global_rad step=45 horizon=horizon45 ### This gives radians as an output! >for i in `seq 92 304`; do r.sun2 -s --o elevin=srtm3_for_global_rad aspin=aspect_for_global_rad slopein=slope_for_global_rad alb=0.23 lin=5.2 horizon=horizon45 horizonstep=45 glob_rad=global_rad_$i day= $i; done ### After Hamish' comments and a bit of testing I found no difference when using different values on the "lat=" parameter. So it really stays out of the game (?) >r.mapcalc global_rad_sum=0 && for i in `seq 92 304`; do r.mapcalc global_rad_sum=global_rad_sum + global_rad_$i; done >r.mapcalc global_daily_avg=global_rad_sum / 212 >r.mapcalc global_daily_avg_kJ="int(global_daily_avg * 3.6)" >r.mapcalc formula="global_daily_avg_kJ / 2450 * (0.025000 * temperature_int + 0.080000)" ### P(otential) E(vapo)T(ranspiration) _______________________________________________ grass-user mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/grass-user
