Medições por covariância de vórtices turbulentos dos fluxos de calor latente, sensível, momentum e co2 sobre o reservatório da usina hidrelétrica de curuá-una – pa

Flux measurements of latent heat, sensible heat, momentum, and CO2 were performed from 15 to 26 June 2015 on the reservoir of the hydroelectric plant Curuá-Una (PA). The flux system is located upstream of the main channel of the reservoir and installed at 3 m above the water surface on a floating structure. The hydroelectric plant Curuá-Una was the first plant built in the Amazonia and it is in operation for almost 40 years. During installation, the vegetation around the river channel was not removed, which led to large emissions of greenhouse gases into the atmosphere. The wind speed was important to maintain turbulent mixing mechanically. Latent heat flux showed significant correlation with the wind velocity (r = 82%). As a result of the combined effect of turbulent mixing generated thermally and mechanically, the latent and sensible heat fluxes were positive throughout the investigation period and the atmospheric surface layer remained unstable. The CO2 flow was predominantly negative (84%), characterizing the reservoir as a CO2 sink.