Advanced search
Start date
(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Ozone production and transport over the Amazon Basin during the dry-to-wet and wet-to-dry transition seasons

Full text
Bela, M. M. [1] ; Longo, K. M. [2] ; Freitas, S. R. [2] ; Moreira, D. S. [2] ; Beck, V. [3] ; Wofsy, S. C. [4] ; Gerbig, C. [3] ; Wiedemann, K. [4] ; Andreae, M. O. [5] ; Artaxo, P. [6]
Total Authors: 10
[1] Natl Inst Space Res INPE, Ctr Earth Syst Sci CCST, Sao Jose Dos Campos - Brazil
[2] Natl Inst Space Res INPE, Ctr Weather Forecast & Climate Studies, Cachoeira Paulista - Brazil
[3] Max Planck Inst Biogeochem, D-07745 Jena - Germany
[4] Harvard Univ, Dept Earth & Planetary Sci, Div Engn & Appl Sci, Cambridge, MA 02138 - USA
[5] Max Planck Inst Chem, Biogeochem Dept, D-55128 Mainz - Germany
[6] Univ Sao Paulo, Inst Phys, Sao Paulo - Brazil
Total Affiliations: 6
Document type: Journal article
Source: Atmospheric Chemistry and Physics; v. 15, n. 2, p. 757-782, 2015.
Web of Science Citations: 12

The Regional Carbon Balance in Amazonia (BARCA) campaign provided the first Amazon Basin-wide aircraft measurements of ozone (O-3) during both the dry-to-wet (November and December 2008) and wet-to-dry (May 2009) transition seasons. Extremely low background values (<20 ppb) were observed to the west and north of Manaus in both seasons and in all regions during the wet-to-dry transition. On the other hand, elevated O-3 levels (40-60 ppb) were seen during the dry-to-wet transition to the east and south of Manaus, where biomass burning emissions of O-3 precursors were present. Chemistry simulations with the CCATT-BRAMS and WRF-Chem models are within the error bars of the observed O-3 profiles in the boundary layer (0-3 km a.s.l.) in polluted conditions. However, the models overestimate O-3 in the boundary layer in clean conditions, despite lacking the predominant NO source from soil. In addition, O-3 simulated by the models was either within the error bars or lower than BARCA observations in mid-levels (3-5 km a.s.l.), and lower than total tropospheric O-3 retrieved from the OMI/MLS instruments, which is primarily comprised of middle troposphere O-3 and thus reflects long-range transport processes. Therefore, the models do a relatively poor job of representing the free troposphere-boundary layer gradient in O-3 compared with aircraft and satellite observations, which could be due to missing long-range and convective transport of O-3 at mid-levels. Additional simulations with WRF-Chem showed that the model O-3 production is very sensitive to both the O-3 deposition velocities and the NOx emissions, which were both about one-half of observed values. These results indicate the necessity of more realistic model representations of emissions, deposition, and convective processes for accurate monitoring and prediction of increases in O-3 production in the Amazon Basin as the regional population grows. (AU)

FAPESP's process: 08/58100-2 - Aeroclima: direct and indirect effects of aerosols on climate in Amazonia and Pantanal
Grantee:Paulo Eduardo Artaxo Netto
Support type: Research Program on Global Climate Change - Thematic Grants