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PÖHLKER, M. L.; DITAS, F.; SATURNO, J.; KLIMACH, T.; ANGELIS, I. H. de; ARAUJO, A. C. de; BRITO, J.; CARBONE, S.; CHENG, Y.; CHI, X.; DITZ, R.; GUNTHE, S. S.; HOLANDA, B. A.; KANDLER, K.; KESSELMEIER, J.; KÖNEMANN, T.; KRÜGER, O. O.; LAVRIC, J. V.; MARTINS, S. T.; MIKHAILOV, E.; MORAN-ZULOAGA, D.; RIZZO, L. V.; ROSE, D.; SU, H.; THALMAN, R.; WALTER, D.; WANG, J.; WOLFF, S.; BARBOSA, H. M. J.; ARTAXO, P.; ANDREAE, M. O.; PÖSCHL, U.; PÖHLKER, C.. |
Size-resolved measurements of atmospheric aerosol and cloud condensation nuclei (CCN) concentrations and hygroscopicity were conducted over a full seasonal cycle at the remote Amazon Tall Tower Observatory (ATTO, March 2014?February 2015). In a preceding companion paper, we presented annually and seasonally averaged data and parametrizations (Part 1; Pöhlker et al., 2016a). In the present study (Part 2), we analyze key features and implications of aerosol and CCN properties for the following characteristic atmospheric conditions: Empirically pristine rain forest (PR) conditions, where no influence of pollution was detectable, as observed during parts of the wet season from March to May. ... |
Tipo: Artigo de periódico |
Palavras-chave: Biomassa; Floresta Tropical. |
Ano: 2018 |
URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1107153 |
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OLVEIRA, P. E. S.; ACEVEDO, O. C.; SÖRGEL, M.; TSOKANKUNKU, A.; WOLFF, S.; ARAUJO, A. C. de; SOUZA, R. A. F.; SÁ, M. O.; MANZI, A. O.; ANDREAE, M. O.. |
Nocturnal turbulent kinetic energy (TKE) and fluxes of energy, CO2 and O3 between the Amazon forest and the atmosphere are evaluated for a 20-day campaign at the Amazon Tall Tower Observatory (ATTO) site. The distinction of these quantities between fully turbulent (weakly stable) and intermittent (very stable) nights is discussed. Spectral analysis indicates that low-frequency, nonturbulent fluctuations are responsible for a large portion of the variability observed on intermittent nights. In these conditions, the low-frequency exchange may dominate over the turbulent transfer. In particular, we show that within the canopy most of the exchange of CO2 and H2O happens on temporal scales longer than 100 s. At 80 m, on the other hand, the... |
Tipo: Artigo de periódico |
Palavras-chave: Energia cinética turbulenta; TKE; Dióxido de Carbono; Vento; Amazonia. |
Ano: 2018 |
URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1091667 |
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ZAHN, E.; DIAS, N. L.; ARAUJO, A.; SÁ, L.; SÖRGEL, M.; TREBS, I.; WOLFF, S.; MANZI, A.. |
An important current problem in micrometeorology is the characterization of turbulence in the roughness sublayer (RSL), where most of the measurements above tall forests are made. There, scalar turbulent fluctuations display significant departures from the predictions of Monin?Obukhov similarity theory (MOST). In this work, we analyze turbulence data of virtual temperature, carbon dioxide, and water vapor in the RSL above an Amazonian forest (with a canopy height of 40?m), measured at 39.4 and 81.6?m above the ground under unstable conditions. We found that dimensionless statistics related to the rate of dissipation of turbulence kinetic energy (TKE) and the scalar variance display significant departures from MOST as expected, whereas the vertical velocity... |
Tipo: Separatas |
Palavras-chave: Climatologia; Floresta Tropical.. |
Ano: 2016 |
URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1055916 |
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ZAHN, E.; DIAS, N. L.; ARAUJO, A.; SÁ, L. D. A.; SÖRGEL, M.; TREBS, I.; WOLFF, S.; MANZI, A.. |
An important current problem in micrometeorology is the characterization of turbulence in the roughness sublayer (RSL), where most of the measurements above tall forests are made. There, scalar turbulent fluctuations display significant departures from the predictions of Monin?Obukhov similarity theory (MOST). In this work, we analyze turbulence data of virtual temperature, carbon dioxide, and water vapor in the RSL above an Amazonian forest (with a canopy height of 40 m), measured at 39.4 and 81.6 m above the ground under unstable conditions. We found that dimensionless statistics related to the rate of dissipation of turbulence kinetic energy (TKE) and the scalar variance display significant departures from MOST as expected, whereas... |
Tipo: Separatas |
Palavras-chave: Climatologia; Floresta Tropical.. |
Ano: 2016 |
URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1053165 |
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ANDREAE, M. O.; ACEVEDO, O. C.; ARAUJO, A.; ARTAXO, P.; BARBOSA, C. G. G.; BARBOSA, H. M. J.; BRITO, J.; CARBONE, S.; CHI, X.; CINTRA, B. B. L.; SILVA, N. F. da; DIAS, N. L.; DIAS-JÚNIOR, C. Q.; DITAS, F.; DITZ, R.; GODOI, A. F. L.; GODOI, R. H. M.; HEIMANN, M.; HOFFMANN, T.; KESSELMEIER, J.; KÖNEMANN, T.; KRÜGER, M. L.; LAVRIC, J. V.; MANZI, A. O.; LOPES, A. P.; MARTINS, D. L.; MIKHAILOV, E. F.; MORAN-ZULOAGA, D.; NELSON, B. W.; NÖLSCHER, A. C.; NOGUEIRA, D. S.; PIEDADE, M. T. F.; PÖHLKER, C.; PÖSCHL, U.; QUESADA, C. A.; RIZZO, L. V.; RO, C.-U.; RUCKTESCHLER, N.; SÁ, L. D. A.; SÁ, M. de O.; SALES, C. B.; SANTOS, R. M. N. dos; SATURNO, J.; SCHÖNGART, J.; SÖRGEL, M.; SOUZA, C. M. de; SOUZA, R. A. F. de; SU, H.; TARGHETTA, N.; TÓTA, J.; TREBS, I.; TRUMBORE, S.; EIJCK, A. van; WALTER, D.; WANG, Z.; WEBER, B.; WILLIAMS, J.; WINDERLICH, J.; WITTMANN, F.; WOLFF, S.; YÁÑEZ-SERRANO, A. M.. |
The Amazon Basin plays key roles in the carbon and water cycles, climate change, atmospheric chemistry, and biodiversity. It already has been changed significantly by human activities, and more pervasive change is expected to occur in the next decades. It is therefore essential to establish long-term measurement sites that provide a baseline record of present-day climatic, biogeochemical, and atmospheric conditions and that will be operated over coming decades to monitor change in the Amazon region as human perturbations increase in the future. The Amazon Tall Tower Observatory (ATTO) has been set up in a pristine rain forest region in the central Amazon Basin, about 150 km northeast of the city of Manaus. An ecological survey including a biodiversity... |
Tipo: Separatas |
Palavras-chave: Monitoramento.; Clima.; Amazonia.. |
Ano: 2015 |
URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1031648 |
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ANDREAE, M. O.; ACEVEDO, O. C.; ARAUJO, A.; ARTAXO, P.; BARBOSA, C. G. G.; BARBOSA, H. M. J.; BRITO, J.; CARBONE, S.; CHI, X.; CINTRA, B. B. L.; SILVA, N. F. da; DIAS, N. L.; DIAS-JÚNIOR, C. Q.; DITAS, F.; DITZ, R.; GODOI, A. F. L.; GODOI, R. H. M.; HEIMANN, M.; HOFFMANN, T.; KESSELMEIER, J.; KÖNEMANN, T.; KRÜGER, M. L.; LAVRIC, J. V.; MANZI, A. O.; LOPES, A. P.; MARTINS, D. L.; MIKHAILOV, E. F.; MORAN-ZULOAGA, D.; NELSON, B. W.; NÖLSCHER, A. C.; NOGUEIRA, D. S.; PIEDADE, M. T. F.; PÖHLKER, C.; PÖSCHL, U.; QUESADA, C. A.; RIZZO, L. V.; RO, C.-U.; RUCKTESCHLER, N.; SÁ, L. D. A.; SÁ, M. de O.; SALES, C. B.; SANTOS, R. M. N. dos; SATURNO, J.; SCHÖNGART, J.; SÖRGEL, M.; SOUZA, C. M. de; SOUZA, R. A. F. de; SU, H.; TARGHETTA, N.; TÓTA, J.; TREBS, I.; TRUMBORE, S.; EIJCK, A. van; WALTER, D.; WANG, Z.; WEBER, B.; WILLIAMS, J.; WINDERLICH, J.; WITTMANN, F.; WOLFF, S.; YÁÑEZ-SERRANO, A. M.. |
The Amazon Basin plays key roles in the carbon and water cycles, climate change, atmospheric chemistry, and biodiversity. It has already been changed significantly by human activities, and more pervasive change is expected to occur in the coming decades. It is therefore essential to establish long-term measurement sites that provide a baseline record of present-day climatic, biogeochemical, and atmospheric conditions and that will be operated over coming decades to monitor change in the Amazon region, as human perturbations increase in the future. |
Tipo: Separatas |
Palavras-chave: Monitoramento.; Clima.; Amazonia.. |
Ano: 2015 |
URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1031153 |
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PFANNERSTILL, E. Y.; NÖLSCHER, A. C.; YÁÑEZ-SERRANO, A. M.; BOURTSOUKIDIS, E.; KEBEL, S.; JANSSEN, R. H. H.; TSOKANKUNKU, A.; WOLFF, S.; SÖRGEL, M.; SÁ, M. O.; ARAUJO, A. C. de; WALTER, D.; LAVRIC, J.; DIAS-JUNIOR, C. Q.; KESSELMEIER, J.; WILLIAMS, J.. |
The 2015/16 El Niño event caused unprecedented drought and warming in the Amazon basin. How tropical forests react to such extreme events in terms of volatile organic compound (VOC) emissions is of interest as the frequency of these events is predicted to increase through climate change. The diverse VOCs emitted can be significant for plants' carbon budgets, influence ozone and particle production, and through their reactivity impact OH concentrations. Total OH reactivity is a directly measureable quantity that gives the reaction frequency of OH radicals with all reactive species in the atmosphere in s?1. Here we present a comparison of the OH reactivity diel cycle from November 2015, i.e., extreme drought and elevated temperatures associated with strong... |
Tipo: Artigo de periódico |
Palavras-chave: El Nino; Amazonia. |
Ano: 2018 |
URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1106635 |
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NÖLSCHER, A. C.; YAÑEZ-SERRANO, A. M.; WOLFF, S.; ARAUJO, A. C. de; LAVRIC, J. V.; KESSELMEIER, J.; WILLIAMS, J.. |
The hydroxyl radical (OH) removes most atmospheric pollutants from air. The loss frequency of OH radicals due to the combined effect of all gas-phase OH reactive species is a measureable quantity termed total OH reactivity. Here we present total OH reactivity observations in pristine Amazon rainforest air, as a function of season, time-of-day and height (0?80 m). Total OH reactivity is low during wet (10 s1) and high during dry season (62 s1). Comparison to individually measured trace gases reveals strong variation in unaccounted for OH reactivity, from 5 to 15% missing in wet-season afternoons to mostly unknown (average 79%) during dry season. During dry-season afternoons isoprene, considered the dominant reagent with OH in rainforests, only accounts for... |
Tipo: Separatas |
Palavras-chave: Sazonalidade.; Floresta.; Amazonia.. |
Ano: 2016 |
URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1045925 |
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