Average variability of temperature and relative humidity of the air in a tropical rain forest in the Brazilian Amazon

Abstract

The Amazon rainforest presents high temperatures and annual precipitation, although there are large interannual variations in these meteorological elements. Air temperature (Tar) and relative air humidity (RH) in and above a forest are the result of complex energy exchanges through the processes of reflection, transmission, and absorption of solar energy. This study was carried out in the Caxiuanã National Forest, Pará, Brasil, and the objective was to evaluate the seasonal variability of air temperature and humidity from a vertical profile analysis within the forest with measures heights of 2, 16, 28 and 42 m, with readings taken every 30 minutes from 2012 to 2016. The results indicated a great seasonality in these meteorological elements, since the highest temperatures occurred at the canopy level (28 m), and the lowest ones were observed near the surface (2 m) due to the attenuation of solar radiation inside the forest. The highest RH values were observed near the surface (2 m), and the lowest values occurred above the canopy, due to the higher wind speeds at this level. These results indicate a large spatial-temporal variability of these meteorological elements, which influence the behavior of living organisms that inhabit that forest environment.