Atmospheric scales of biotic dispersal

Recent advances in meteorological technologies and techniques are providing new insight into microscale, mesoscale, and macroscale aerobiological processes. For example, Lidar systems have identified microscale characteristics of atmospheric turbulence over agricultural fields which cannot be readily determined by conventional (site-specific) atmospheric sensors. Also, neutrally buoyant superpressure balloons (tetroons) have been tracked more than 400 km per night indicating atmospheric pathways of migrating insects between agricultural regions in south-central Texas. Such atmospheric trajectories often reveal substantial day-to-day variation of aerobiological pathways and, consequently, affect the risk of pest infestations and host infections. Further, the NEXRAD network of WSR-88D Doppler weather radars can measure the aerial abundance, speed, and displacement direction of concentrated biota over areas of> 1000 km². Emphasis is placed on identifying biologically-relevant, temporal and spatial scales of atmospheric motion and other atmospheric variables which help control the abundance and dispersal of airborne biota, specifically insects, spores, pollen, fungi, and plant pathogens. Major technologies, including the NEXRAD network of WSR-88D Doppler weather radars, are described, and examples are presented for aerobiological applications. (C) 1999 Published by Elsevier Science B.V.