The scientific goal of this FAPESP proposal is to estimate greenhouse gas balances of the Amazon over a period of approximately one decade and to relate the observed inter-annual variation to climate anomalies, climate change and human alteration of the land surface, like e.g. deforestation. The relevance for this research is the concern about potential feedbacks of Amazonian forest changes on global climate and tropical South America's hydrological cycle, affecting not only the globe but also a large 'local' human population. Our main proposal follows an atmospheric approach towards answering the questions how Amazonian greenhouse gas balances change over time as a diagnostic of its state. In simple words this approach consists in measuring the lower to mid- troposphere greenhouse gas concentration fields above the basin along the main air-stream. From concentration gradients along the airstream - either accumulation or depletion - greenhouse gas fluxes can then be estimated. An increase in column content implies a source along the air-stream and vice versa. In broad terms the main air-stream consists of a loop starting with air entering the basin along the North-east coast of brazil from the East. Air masses then travel towards the Andes where they are being steered southwards by topography and finally deflected back towards the Atlantic along the Southern rim of the Amazon Basin. Clearly information on atmospheric transport rates and mixing are needed to make this approach rigorous, which can for example be provided by atmospheric air and air constituent transport models. The atmospheric sampling approach taken here is to sample the lower troposphere in full by sampling vertical profiles using aircraft.
News published in Agência FAPESP Newsletter about the scholarship: