[1] The collapse of the Laurentide Ice Sheet over Hudson Bay 8.47 ka allowed the rapid drainage of glacial Lake Agassiz into the Labrador Sea, an event identified as causing a reduction in Atlantic meridional overturning circulation (AMOC) and the 8.2 ka cold event. Atmosphereocean models simulations based on this forcing, however, fail to reproduce several characteristics of this event, partic...

Wellsch Valley tephra, near Swift Current, southwestern Saskatchewan, and Galt Island Medicine Hat, southeastern Alberta, have been referenced in the literature since 1970s, but little is available on their physical chemical attributes – necessary information if they are to be recognized elsewhere. This study seeks remedy this situation. Both a calc-alkaline rhyolitic composition with hornblend...

We examined the relationship between satellite measurements of solar-induced chlorophyll fluorescence (SIF) and several meteorological drought indices, including the multi-time-scale standard precipitation index (SPI) and the Palmer drought severity index (PDSI), to evaluate the potential of using SIF to monitor and assess drought. We found significant positive relationships between SIF and dro...

The potential of arid/semiarid land plants a s sources of commercial products is illustrated by the following examples: candelilla (wax); jojoba (oil, protein); Acacia spp. (gum); Astragalus spp. (tragacanth gum); guayule (rubber); rabbitbrush (rubber, chemicals); sunflowers (rubber, chemicals); yucca (soap); and cresote bush (antioxidants, phenolic resins). co-evolutionary selection is a cause...

Orbital observations by the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft are used to re-evaluate the nature and origin of the oldest mapped plains deposits on Mercury, the intercrater and intermediate plains units defined by Mariner 10 investigators. Despite the large areal extent of these plains, which comprise approximately one-third of the planetary su...

J. Med. Entomol. 25(1): 32-38 (1988) ABSTRACT Seasonal abundance of ectoparasites was estimated from monthly collections of Eastern (Sturnella magna (L.)) and Western (Sturnella neglecta Audubon) meadowlarks in Starr County, Tex. Ecological relationships of ticks, Amblyomma maculatum Koch, Amblyomma inornatum (Banks), and Haemaphysalis leporispalustris (Packard) (Acari: Ixodidae); lice, Menacan...