A climate analysis considering cyanobacetria blooms in an urban subtropical drinking water reservoir

The continual environmental degradation in water basins with intense human occupation has significantly altered the quality of water, triggering cyanobacteria blooms in urban lakes and fresh water reservoirs. Studies indicate... [ view full abstract ]

The continual environmental degradation in water basins with intense human occupation has significantly altered the quality of water, triggering cyanobacteria blooms in urban lakes and fresh water reservoirs. Studies indicate potential carcinogenic and other harmful effects on health of Microcystis aeruginosa (cyanobacteria) in drinking water. Cyanobacteria blooms are becoming an increasingly common phenomenon worldwide, when it occurs in drinking water reservoirs it may represent a public health risk. In accordance with seasonality, there is a greater or lesser proliferation of cyanobacteria, also known as blue algae. The aim of this study is to demonstrate the relationship between cyanobacteria blooms in the drinking water from the Guarapiranga Reservoir and climate and weather types, of the Metropolitan Region of São Paulo´s in the time space between 2010 and 2013. Meteorological data obtained from the Institute of Astronomy, Geophysics and Atmospheric Sciences at the University of São Paulo meteorological station have been analyzed, as well as the results of laboratory analysis of reservoir water, provided by the basic sanitation company of the State of São Paulo. Result show that Cold Front, conflict between masses and the Tropical Instability Line have important role in the triggering process of cyanobacteria blooms, the cyanobacteria density may be associated with high air temperatures, rainfall and wind intensity, especially during the rainy season (October to March). Climate change in the city of São Paulo can worsen these problems related to drinking water once the ideal climatic conditions for the proliferation of cyanobacteria are increasing in frequency. Especially in the last 20 years. This scenario can magnify a public health problem related to cyanobacteria in São Paulo- Brazil and around the world, once that climate change may increase public health risks related to drinking water quality as associated with land use.