Observations made at TA-41 in Los Alamos canyon show that atmospheric flow in canyons is quite different from flow over the plateau. This gravity flow is steady and continues for an hour or two after sunrise when it abruptly ceases and is followed by an unsteady up-canyon flow for a couple of hours. Down-canyon flow begins again around sunset, but the onset time appears to be more variable than cessation time in the morning. Rotors have been observed at night, but they are very rare. Other things being equal, this value is larger than would be observed over flatter, smoother sites.
Statistics vary from station to station.
Energy Exchange at the Surface . About half of this absorbed shortwave energy is offset by longwave radiation to space.