Global Climate Change Response Program. Part 1. Potential Effects of GlobalChange on Chlorophyll alpha Concentrations in a Southwestern Desert Reservoir: Las Vegas Bay, Lake Mead, Nevada. Part 2. Simulated Impacts of a Double CO2 Climate on the Location o

摘要

Three algal bioassay experiments were conducted from March 1992 through September1993 in an area of Lake Mead that has experienced problems associated with severe nutrient enrichment. The first experiment determined the effects of elevated CO2 (700 ppm) (2xCO2), vs ambient CO2 on the natural algal assemblage without nutrient enrichment. The second experiment determined the effects of 2xCO2 on nutrient enriched bioassays and if nutrients were limiting. The third experiment examined elevated temperatures and 2xCO2. Nested climate models were used to predict changes in water temperatures and thermocline development in Las Vegas Bay. The lake model predicted an increase in mean water temperatures of 1.8 deg under a 2xCO2 scenario. A thermocline definition of 1 deg. C change per 2-m depth was applied to water temperatures developed by a lake model coupled to nested general circulation and regional-scale atmospheric models in 3-year simulations of the current and double-CO2 climates.