ALMA Memo No. 487 Lightning Near Cerro Chascón
نویسندگان
چکیده
We present a preliminary analysis of the spatial and seasonal lightning distribution near the Cerro Chascón science preserve, probed with a space-borne imaging sensor and groundbased storm detectors. The lightning flash rate in this area is among the lowest in the world for comparable latitudes. Thunderstorms only occur around 5 days per year. Most observed lightning strikes occurred far to the east of Cerro Chascón, in Bolivia and Argentina. Lightning was detected primarily during the summer (December–March), particularly in the afternoon and evening (UT = 16h–1h). Morning (UT = 10h–14h) events were rare. There seem to be two types of storms — heavy storms from the west, and milder, but more common, storms from the east. No significant difference was found between the strike rates at Pampa La Bola and at Llano de Chajnantor.
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ALMA Memo 326 Vertical Pro les of Soil Resistivity at Pampa La Bola and Llano de Chajnantor Locations
We report results of resistivity sounding of eight locations in the Cerro Chasc on science preserve area. The soil resistivity near the surface was found to be 1000 m at the ve locations in the Pampa La Bola area. The values at the three locations in the Llano de Chajnantor area were much higher, exceeding 3500 m. This di erence probably re ects di erences in water content in the upper soil lay...
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