scholarly journals Cloud Characteristics, Thermodynamic Controls and Radiative Impacts During the Observations and Modeling of the Green Ocean Amazon (GoAmazon2014/5) Experiment

2017 ◽  
Author(s):  
Scott E. Giangrande ◽  
Zhe Feng ◽  
Michael P. Jensen ◽  
Jennifer Comstock ◽  
Karen L. Johnson ◽  
...  

Abstract. Routine cloud, precipitation and thermodynamic observations collected by the ARM Mobile Facility (AMF) and Aerial Facility (AAF) during the two-year DOE ARM Observations and Modeling of the Green Ocean Amazon (GoAmazon2014/5) campaign are summarized. These observations quantify the diurnal to large-scale thermodynamic regime controls on the clouds and precipitation over the undersampled, climatically important, Amazon basin region. The extended ground deployment of cloud-profiling instrumentation enabled a unique look at multiple cloud regime controls at high temporal and vertical resolution. This longer-term ground deployment coupled with two short-term aircraft intensive observing periods allowed new opportunities to better characterize cloud and thermodynamic observational constraints as well as cloud radiative impacts for modeling efforts within typical Amazon ‘wet’ and ‘dry’ seasons.

2017 ◽  
Vol 17 (23) ◽  
pp. 14519-14541 ◽  
Author(s):  
Scott E. Giangrande ◽  
Zhe Feng ◽  
Michael P. Jensen ◽  
Jennifer M. Comstock ◽  
Karen L. Johnson ◽  
...  

Abstract. Routine cloud, precipitation and thermodynamic observations collected by the Atmospheric Radiation Measurement (ARM) Mobile Facility (AMF) and Aerial Facility (AAF) during the 2-year US Department of Energy (DOE) ARM Observations and Modeling of the Green Ocean Amazon (GoAmazon2014/5) campaign are summarized. These observations quantify the diurnal to large-scale thermodynamic regime controls on the clouds and precipitation over the undersampled, climatically important Amazon basin region. The extended ground deployment of cloud-profiling instrumentation enabled a unique look at multiple cloud regimes at high temporal and vertical resolution. This longer-term ground deployment, coupled with two short-term aircraft intensive observing periods, allowed new opportunities to better characterize cloud and thermodynamic observational constraints as well as cloud radiative impacts for modeling efforts within typical Amazon wet and dry seasons.


1999 ◽  
Vol 77 (8) ◽  
pp. 1223-1232 ◽  
Author(s):  
John F Wilmshurst ◽  
John M Fryxell ◽  
Brian P Farm ◽  
ARE Sinclair ◽  
Chris P Henschel

We investigated the spatial distribution of radio-marked wildebeest (Connochaetes taurinus) in the Serengeti ecosystem in relation to the distribution of their food resources, comparing patterns in the wet and dry seasons and at local and landscape spatial scales. A mechanistic model of ruminant energy optimization predicted that wildebeest should maximize energy intake on swards 3 cm high and maintain energy balance on swards between 3 and 10 cm high. At the ecosystem scale, wildebeest preferred short and intermediate-height grass of moderate greenness during both the wet and dry seasons. This was consistent with the model prediction which suggests that large-scale movements by wildebeest are motivated, at least partially, by an energy-maximizing strategy. At the local scale, however, wildebeest showed spatial selectivity only on the basis of grass greenness, not on grass height. This differed from model expectations and may have resulted from wildebeest exploiting ephemeral green flushes of grass caused by localized rainfall in their movement radius. According to these results, the influence of other nutritional or behavioural factors on wildebeest distributions is not rejected, yet they suggest the potentially important role of an energy intake maximizing strategy on movement patterns. Our findings show that wildebeest movements are broadly similar to those of other large herbivores that migrate in response to resource gradients.


2017 ◽  
Vol 35 (3) ◽  
Author(s):  
Newton Silva de Lima ◽  
Julio Tota da Silva ◽  
Maurício José Alves Bolzam ◽  
Alan Dos Santos Ferreira ◽  
Matheus Da Rocha Pietzsch

ABSTRACT. This work used micrometeorological measurements of temperature and wind in order to characterize the turbulence due to wind in a terra firme forest in central Amazonia as part of the ATTO-CLAIRE / IOP-1 (2012) (Amazon Tall Tower Observatory – Cooperative LBA Airborne Regional Experiment / Intensive Observation Period – 2012 / LBA – Large Scale Biosphere-Atmosphere Experiment in the Amazon). This research was conducted at the Uatumã ATTO Sustainable Development Reserve in the State of Amazonas, Brazil, from February to September, 2012, and used data from February 26 to September 07, 2012, dates that partially encompass the wet and dry seasons, respectively. The ATTO site has 5 towers: one that is 320m, and four that are 80 m in height, and this research was conducted on an 80 m triangular tower. A total of ten 3D and 2D ultrasonic anemometers were installed on the tower, and the importance of these instruments used for flux measurements is also evident when taking into account the fact that the dissemination and diffusion of seeds and chemical composts in the forest happens through the action of turbulent fluxes. In order to understand the wind profile, the inflection point of the wind velocity, and coherent structures (ECs) and local turbulence, box-plot diagrams, quadrant analyses, wavelet potential spectrum, and energy potential analyses were conducted. The turbulence characterized at the ATTO had a roll or ramp structure during the study period, which represents favorable conditions for the maintenance of the forest during the wet and dry seasons in the Central Amazon. Keywords: inflection point, ramp, wavelet, turbulence. RESUMO. Este trabalho faz uso de medidas micrometeorológicas de temperatura e vento, com finalidade de caracterizar a turbulência aerotransportada em uma floresta de terra firme na Amazônia Central, realizadas no experimento ATTO-CLAIRE / IOP-1 (2012) (Amazon Tall Tower Observatory – Cooperative LBA Airborne Regional Experiment / Intensive Observation Period – 2012 / LBA – Large Scale Biosphere-Atmosphere Experiment in Amazônia), no sítio do ATTO, na Reserva de Desenvolvimento Sustentável do Uatumã – AM (Brasil) nos meses de fevereiro a setembro de 2012, com dados analisados a partir do dia 26 de fevereiro de 2012 até o dia 7 de setembro de 2012, entre as estações úmida e seca na Amazônia Central, no complexo de torres altas composta de 5 (cinco) torres; uma de 320 m e 4 (quatro) de 80 m. Este trabalho foi realizado na torre triangular (80 m). Foram instalados 10 (dez) anemômetros ultrassônicos de 3D e 2D. Equipamentos necessários em método de fluxos, visto que, a disseminação e difusão de sementes e compostos químicos da floresta, faz-se também por fluxos turbulentos. Para compreensão do perfil de vento, ponto de inflexão do perfil da velocidade do vento, estruturas coerentes e a turbulência local, para tal desenvolveu-se a partir dos dados processados, diagrama de caixa (box-plot ), análise de quadrantes, espectro de potência em ondeletas, espectro de energia. A turbulência caracterizada no ATTO, foi de estruturas do tipo “rolo” ou rampa, para o período estudado, condições favoráveis para manutenção da floresta em período úmido-seco na Amazônia Central.Palavras-chave: ponto de inflexão, rampa, ondeleta, turbulência.


2015 ◽  
Vol 57 (6) ◽  
pp. 497-503 ◽  
Author(s):  
Rubens Souza de OLIVEIRA ◽  
Lanna Jamile Corrêa da COSTA ◽  
Fernanda Atanaena Gonçalves de ANDRADE ◽  
Wilson UIEDA ◽  
Luzia Fátima Alves MARTORELLI ◽  
...  

The outbreaks of rabies in humans transmitted by Desmodus rotundus in 2004 and 2005, in the northeast of the Brazilian State of Para, eastern Amazon basin, made this a priority area for studies on this zoonosis. Given this, the present study provides data on this phenomenon in an urban context, in order to assess the possible circulation of the classic rabies virus (RABV) among bat species in Capanema, a town in the Amazon basin. Bats were collected, in 2011, with mist nets during the wet and dry seasons. Samples of brain tissue and blood were collected for virological and serological survey, respectively. None of the 153 brain tissue samples analyzed tested positive for RABV infection, but 50.34% (95% CI: 45.67-55.01%) of the serum samples analyzed were seropositive. Artibeus planirostris was the most common species, with a high percentage of seropositive individuals (52.46%, 95% CI: 52.31 52.60%). Statistically, equal proportions of seropositive results were obtained in the rainy and dry seasons (c2 = 0.057, d.f. = 1, p = 0.88). Significantly higher proportions of males (55.96%, 95% CI: 48.96-62.96%) and adults (52.37%, 95% CI: 47.35-57.39%) were seropositive. While none of the brain tissue samples tested positive for infection, the high proportion of seropositive specimens indicates that RABV may be widespread in this urban area.


2012 ◽  
Vol 77 (1) ◽  
pp. 138-148 ◽  
Author(s):  
Barbara Hermanowski ◽  
Marcondes Lima da Costa ◽  
Hermann Behling

New pollen, micro-charcoal, sediment and mineral analyses of a radiocarbon-dated sediment core from the Serra Sul dos Carajás (southeast Amazonia) indicate changes between drier and wetter climatic conditions during the past 25,000 yr, reflected by fire events, expansion of savanna vegetation and no-analog Amazonian forest communities. A cool and dry last glacial maximum (LGM) and late glacial were followed by a wet phase in the early Holocene lasting for ca. 1200 yr, when tropical forest occurred under stable humid conditions. Subsequently, an increasingly warm, seasonal climate established. The onset of seasonality falls within the early Holocene warm period, with possibly longer dry seasons from 10,200 to 3400 cal yr BP, and an explicitly drier phase from 9000 to 3700 cal yr BP. Modern conditions with shorter dry seasons became established after 3400 cal yr BP. Taken together with paleoenvironmental evidence from elsewhere in the Amazon Basin, the observed changes in late Pleistocene and Holocene vegetation in the Serra Sul dos Carajás likely reflect large-scale shifts in precipitation patterns driven by the latitudinal displacement of the Inter-Tropical Convergence Zone and changes in sea-surface temperatures in the tropical Atlantic.


2020 ◽  
Author(s):  
Shujiro Komiya ◽  
Jost Lavric ◽  
David Walter ◽  
Santiago Botia ◽  
Alessandro Araujo ◽  
...  

<p>Amazon rainforests and soils contain large amounts of carbon, which is under pressure from ongoing climate and land use change in the Amazon basin. It is estimated that methane (CH<sub>4</sub>), an important greenhouse gas, is largely released from the flooded wetlands of the Amazon, but the trends and balances of CH<sub>4 </sub>in the Amazon rainforest are not yet well understood. In addition, the change in atmospheric CH<sub>4</sub> concentration is strongly associated with a change in carbon monoxide (CO) concentration, often caused by the human-induced combustion of biomass that usually peaks during dry season. Understanding the long-term fluctuations in the fluxes of greenhouse gases in the Amazon rainforest is essential for improving our understanding of the carbon balance of the Amazon rainforest.</p><p>Since March 2012, we have continuously measured atmospheric CO<sub>2</sub>/CH<sub>4</sub>/CO concentrations at five levels (79, 53, 38, 24, and 4 m a.g.l.) using two wavelength-scanned cavity ring-down spectroscopy analyzers (G1301 and G1302, Picarro Inc., USA), which are automatically calibrated on site every day. In addition, we measured the CO<sub>2</sub> flux by the eddy covariance method at the same tower. We estimated the CO<sub>2</sub>/CH<sub>4</sub>/CO fluxes by combining the vertical profile of the CO<sub>2</sub>/CH<sub>4</sub>/CO concentrations with the flux gradient method. Our results generally show no major difference in CO<sub>2</sub> flux between the wet and dry seasons except for year 2017, when an elevated CO<sub>2</sub> uptake was documented during the dry season despite the lowest precipitation between 2014 and 2018. The CH<sub>4</sub> flux showed the largest CH<sub>4</sub> emission during the dry season in year 2016. Further results will be analyzed and discussed in the presentation.</p>


Water ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 2263 ◽  
Author(s):  
Lwimbo ◽  
Komakech ◽  
Muzuka

This paper assesses the impacts of farmers’ intensive use of agrochemicals (fertilizers and pesticides) on groundwater quality in the Kahe catchment. Samples were collected during the wet and dry seasons of the year 2018 and analyzed for the presence of agrochemicals in the water. Groundwater chemistry was dominated by magnesium-sodium-bicarbonate (Mg-Na-HCO3−). The cations levels were in the trend of Mg2+ >Na+ > Ca2+ > K+, whereas anions were HCO3− > Cl− > SO42− for both seasons. The NO3− had an average value of about 18.40 ± 4.04 and 7.6 ± 1.7 mg/L in the wet and dry season, respectively. Elevated levels of nitrate, sulfate, phosphate, and ammonium were found in water samples collected near the large-scale sugarcane plantation in the catchment. For both seasons, Pb, Cd, Fe, Mn, Zn and Cu concentrations averaged approximately 0.08 ± 0.03, 0.11 ± 0.03, 0.16 ± 0.02, 0.11 ± 0.01, 0.46 ± 0.05, and 0.55 ± 0.02 mg/L, respectively. On the other hand, the concentrations were higher in shallow wells than in the deep boreholes. Pesticides’ residues were below the detection limit in all sampled groundwater. The findings from this study provide important information for intervention in groundwater quality management in Kahe Catchment, Tanzania.


2016 ◽  
Vol 17 (12) ◽  
pp. 3079-3097 ◽  
Author(s):  
Virendra P. Ghate ◽  
Pavlos Kollias

Abstract The Amazon plays an important role in the global energy and hydrological budgets. The precipitation during the dry season (June–September) plays a critical role in maintaining the extent of the rain forest. The deployment of the first Atmospheric Radiation Measurement (ARM) Mobile Facility (AMF-1) in the context of the Green Ocean Amazon (GOAmazon) field campaign at Manacapuru, Brazil, provided comprehensive measurements of surface, cloud, precipitation, radiation, and thermodynamic properties for two complete dry seasons (2014 and 2015). The precipitation events occurring during the nighttime were associated with propagating storm systems (nonlocal effects), while the daytime precipitation events were primarily a result of local land–atmosphere interactions. During the two dry seasons, precipitation was recorded at the surface on 106 days (43%) from 158 rain events with 82 daytime precipitation events occurring on 64 days (60.37%). Detailed comparisons between the diurnal cycles of surface and profile properties between days with and without daytime precipitation suggested the increased moisture at low and midlevels to be responsible for lowering the lifting condensation level, reducing convective inhibition and entrainment, and thus triggering the transition from shallow to deep convection. Although the monthly accumulated rainfall decreased during the progression of the dry season, the contribution of daytime precipitation to it increased, suggesting the decrease to be mainly due to reduction in propagating squall lines. The control of daytime precipitation during the dry season on large-scale moisture advection above the boundary layer and the total rainfall on propagating squall lines suggests that coarse-resolution models should be able to accurately simulate the dry season precipitation over the Amazon basin.


2020 ◽  
Vol 34 (10) ◽  
pp. 13849-13850
Author(s):  
Donghyeon Lee ◽  
Man-Je Kim ◽  
Chang Wook Ahn

In a real-time strategy (RTS) game, StarCraft II, players need to know the consequences before making a decision in combat. We propose a combat outcome predictor which utilizes terrain information as well as squad information. For training the model, we generated a StarCraft II combat dataset by simulating diverse and large-scale combat situations. The overall accuracy of our model was 89.7%. Our predictor can be integrated into the artificial intelligence agent for RTS games as a short-term decision-making module.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
P. O. Olsson ◽  
A. H. Tinson ◽  
N. Al Shamsi ◽  
K. S. Kuhad ◽  
R. Singh ◽  
...  

AbstractCloning, through somatic cell nuclear transfer (SCNT), has the potential for a large expansion of genetically favorable traits in a population in a relatively short term. In the present study we aimed to produce multiple cloned camels from racing, show and dairy exemplars. We compared several parameters including oocyte source, donor cell and breed differences, transfer methods, embryo formation and pregnancy rates and maintenance following SCNT. We successfully achieved 47 pregnancies, 28 births and 19 cloned offspring who are at present healthy and have developed normally. Here we report cloned camels from surgical embryo transfer and correlate blastocyst formation rates with the ability to achieve pregnancies. We found no difference in the parameters affecting production of clones by camel breed, and show clear differences on oocyte source in cloning outcomes. Taken together we demonstrate that large scale cloning of camels is possible and that further improvements can be achieved.


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