A Note on the FM-CW radar as a remote probe of the pacific trade-wind inversion

Abstract

Abstract. A vertically pointed FM-CW radar was used to monitor the Pacific Trade-Wind Inversion in the Hawaiian Islands during the summer of 1971. An instrumented aircraft was used for in situ measurements of radio refractivity and temperature. The correspondence between the position of the radar returns and the aircraft data was excellent. The strong returns seen by the radar were due chiefly to the strong lapse of humidity across the inversion.The radar indicated that over the island of Lanai the trade-wind inversion was highly variable both in position and intensity. At times the layer would move from above 2 km to less than 1 km in the space of five minutes associated with strong mechanical turbulence. Its thickness would change rapidly from tens of meters to hundreds of meters. Wave-like structure induced by the mountains on the east side were observed by the radar.Our analysis indicates that interpretation of in situ aircraft measurements may be greatly aided by using the FM-CW radar as a guide.

Remote Sensing for Air Pollution Meteorology

“…The marine inversion layer, as well as layers associated with continental radiation inversions, have been detected with FM/CW radars (Gossard and Richter, 1970;Bean et al, 1973). The refractive index change that produces the signal returned to an FM/CW radar is probably more strongly a function of humidity than temperature.…”