Mark A. Bourassa

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—This effort continues a study of the effects of rain, over the oceans, on the signal retrieved by the SeaWinds scatterom-eter. It is determined that the backscatter radar cross section can be used to estimate the volumetric rain rate, averaged horizontally, across the surface resolution cells of the scatterometer. The dual polarization of the radar has a(More)
Normal right-handed subjects were required to make pitch comparisons of complex tones in which the fundamental frequency was either present or absent. In both conditions, tones were presented monaurally. An increase in left-ear superiority was observed in the response time measurements when the fundamental was absent. These findings support the notion that(More)
The internal transcribed spacer (ITS) of the ribosomal DNA (rDNA) subunit repeat was sequenced in 12 isolates of Cylindrocladium floridanum and 11 isolates of Cylindrocarpon destructans. Sequences were aligned and compared with ITS sequences of other fungi in GenBank. Some intraspecific variability was present within our collections of C. destructans but(More)
25 2 26 Short summary: High latitudes present extreme conditions for the measurement and estimation of air– 27 sea and ice fluxes, limiting understanding of related physical processes and feedbacks that are 28 important elements of the Earth's climate. 29 30 Abstract: Polar regions have great sensitivity to climate forcing; however, understanding of the 31(More)
A method of correcting the errors caused by rain, to the normalized radar cross section measured by spaceborne scatterometers is presented. The simultaneous, collocated measurements of the vertical precipitation profile by the TRMM and AMSR passive radiometers are converted into reflectivity and attenuation to develop a method for removing the effects of(More)
ABSTRACT Poplar leaf rust caused by Melampsora medusae f. sp. deltoidae is a widespread disease in North America, where epidemics occur within zones of sympatry and allopatry of telial hosts (Populus spp.) and aecial hosts (Larix spp.). To test the hypothesis that epidemics originate in the zone of sympatry where the rust can complete its life cycle,(More)