SciELO - Scientific Electronic Library Online

vol.34 issue4Diurnal variability of rainfall in southwest Amazonia during the LBA-TRMM field campaign of the austral summer of 1999Meteorological effects of a cold spell event over Amazonia: a case study author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Services on Demand




Related links


Acta Amazonica

Print version ISSN 0044-5967On-line version ISSN 1809-4392


MOURA, Marcos Antonio Lima et al. Observational evidence of lake breezes at Balbina lake (Amazonas, Brazil) and their effect on ozone concentrations. Acta Amaz. [online]. 2004, vol.34, n.4, pp.605-611. ISSN 0044-5967.

Local wind systems, such as sea or lake breezes, strongly affect the transport and dispersion of atmospheric trace gases. Based on its size and location, the artificial lake of Balbina in the Amazon - can be expected to give rise to a lake/forest breeze regime. During the period 2 to 28 July 2002, within the LBA/CLAIRE-2001 experiment, we have continually measured the ozone concentrations (O3) and the wind directions close to the Balbina dam. We found that there is indeed a well established breeze system, with lake breezes prevailing during mid-day (10 to 14 LT) while forest breezes prevail from the afternoon to early morning (16 to 8 LT). During the latter period radioactive cooling in the forest creates a strong local thermal contrast. The average daily ozone concentration was 8.7 ppbv, with an average of 10.6 ppbv during the day, and 3.5 ppbv at night. When local winds came from the lake, even at night, ozone concentrations were greater compared to breezes coming from the forest.

Keywords : Amazonian Forest; Lake; Breeze; Ozone.

        · abstract in Portuguese     · text in Portuguese     · Portuguese ( pdf )


Creative Commons License All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License