A5034360328- Wind and Air Flow Studies
- Meteorological Phenomena and Simulations
- Fluid Dynamics and Turbulent Flows
- Plant Water Relations and Carbon Dynamics
- Atmospheric and Environmental Gas Dynamics
- Climate variability and models
- Atmospheric aerosols and clouds
- Geography and Environmental Studies
- Atmospheric chemistry and aerosols
- Environmental and biological studies
- Aeolian processes and effects
- Air Quality and Health Impacts
- Solar Radiation and Photovoltaics
- Geophysics and Gravity Measurements
- Plant responses to elevated CO2
- Oceanographic and Atmospheric Processes
- Tropical and Extratropical Cyclones Research
- Remote Sensing in Agriculture
- Atmospheric Ozone and Climate
- Combustion and flame dynamics
- Probabilistic and Robust Engineering Design
- Fluid Dynamics and Vibration Analysis
- Aerodynamics and Fluid Dynamics Research
- Precipitation Measurement and Analysis
- Wind Energy Research and Development
University of Oklahoma
2023-2024
Universidade Federal de Santa Maria
2014-2023
Universidade Federal do Pampa
2013-2023
Institute of Atmospheric Sciences and Climate
2023
Instituto Federal de Educação, Ciência e Tecnologia de Santa Catarina
2022
Amazon (United States)
2016
Domus Medica
2016
Natura (Brazil)
2013
Governo do Estado do Rio Grande do Sul
2013
National Institute for Space Research
2013
Abstract. The Amazon Basin plays key roles in the carbon and water cycles, climate change, atmospheric chemistry, biodiversity. It has already been changed significantly by human activities, more pervasive change is expected to occur coming decades. therefore essential establish long-term measurement sites that provide a baseline record of present-day climatic, biogeochemical, conditions will be operated over decades monitor region, as perturbations increase future. Tall Tower Observatory...
Different aspects of the stable boundary‐layer structure are contrasted between very and weakly regimes from a new point view. This study finds limit wind speed, referred to as crossover threshold , when average vertical gradient turbulent kinetic energy switches sign at all observational levels. When speed exceeds this transition, entire boundary layer becomes vertically fully coupled. Consequently in is considered decoupled regime, while state coupled regime . It shown that profiles other...
At the time of leaf emergence in deciduous forests, markedly enhanced evapotranspiration leads to a rapid drop Bowen ratio. A small fraction this surface flux alteration converges into boundary layer, and can be detected mean temperature humidity daily increments at surface. simple technique is presented for identifying response climate data extracting series date spring onset “spring intensity,” measure energy budget partition change spring. tendency ratio B′ found from changes increment...
On clear nights with appreciable radiative cooling, rates of change mean quantities observed in the first 1 or 2 h after sunset are many times larger than they subsequently until sunrise. These variations include large temperature drops, specific humidity increases, and abrupt wind speed decay. The early evening transition (EET) is dominated by vertical surface flux convergence as turbulent mixing layer becomes confined to a shallow stable near surface. Effects heterogeneities enhanced...
Abstract Previous observational studies in the stable boundary layer diverge appreciably on values of dimensionless ratios between turbulence-related quantities and their stability dependence. In present study, hypothesis that such variability is caused by influence locally dependent nonturbulent processes, referred to as submeso, tested confirmed. This done using six datasets collected at sites with different surface coverage. The time-scale dependence wind components temperature...
Abstract We describe the salient features of a field study whose goals are to quantify vertical distribution plant-emitted hydrocarbons and their contribution aerosol cloud condensation nuclei production above central Amazonian rain forest. Using observing systems deployed on 50-m meteorological tower, complemented with tethered balloon deployments, aerosols was determined under different boundary layer thermodynamic states. The forest emits sufficient reactive hydrocarbons, such as isoprene...
Abstract Physical processes represented by the Monin–Obukhov bulk formula for momentum are investigated with field observations. We discuss important differences between turbulent mixing most energetic non-local, large, coherent turbulence eddies and local as traditionally K-theory (analog to molecular diffusion), especially in consideration of developing surface-layer stratification. The study indicates that neutral state a horizontally homogeneous surface layer described represents special...
Abstract To study how changing agricultural practices in the eastern Amazon affect carbon, heat and water exchanges, a 20 m tower was installed field August 2000. Measurements include turbulent fluxes (momentum, heat, vapor, CO 2 ) using eddy covariance (EC) approach, soil flux, wind, scalar profiles ( T , q ), moisture content, terrestrial, total solar radiation, photosynthetically active radiation (PAR, 400–700 nm). At beginning of measurements, September 2000, pasture. On November 2001,...
Do the influences of river breezes or other mesoscale effects lead to a systematic proximity bias in Amazon rainfall data? We analyzed for network 38 rain gauges located near confluence Tapajós and rivers eastern Basin. Tipping bucket worked adequately regime, but careful field calibration comparison with collocated conventional were essential incorporate daily totals from our array into regional maps. Stations very large miss afternoon convective rain, as expected if breeze promotes...
Abstract Simultaneous profiles of turbulence statistics and mean ozone mixing ratio are used to establish a relation between eddy diffusivity within the Amazon forest. A one‐dimensional diffusion model is proposed infer time scales from profiles. Data results indicate that during daytime conditions, upper (lower) half canopy well (partially) mixed most vertical extent forest can be in less than an hour. During nighttime, predominantly poorly mixed, except for periods with bursts intermittent...
Abstract Intermittent transitions between turbulent and nonturbulent states are ubiquitous in the stable atmospheric surface layer (ASL). Data from two field experiments Utqiaġvik, Alaska, direct numerical simulations used to probe these state so as (i) identify statistical metrics for detection of intermittency, (ii) physical origin bursts, (iii) quantify intermittency effects on overall fluxes their representation closure models. The analyses reveal three turbulence regimes, which...
This study analyzes and discusses data taken from oceanic atmospheric measurements performed simultaneously at the Brazil‐Malvinas Confluence (BMC) region in southwestern Atlantic Ocean. area is one of most dynamical frontal regions world ocean. Data were collected during four research cruises once a year consecutive years between 2004 2007. Very few studies have addressed importance studying air‐sea coupling BMC region. Lateral temperature gradients as high 0.3°C km −1 surface subsurface....
Horizontal and vertical CO 2 fluxes gradients were made in an Amazon tropical rain forest, the Tapajós National Forest Reserve (FLONA‐Tapajós: 54°58′W, 2°51′S). Two observational campaigns 2003 2004 conducted to describe subcanopy flows, clarify their relationship winds above estimate how they may transport horizontally. It is now recognized that of respired missed by budgets rely only on single point eddy covariance measurements, with error being most important under nocturnal calm...
Abstract A model for the exchange between surface and atmosphere under stable conditions is proposed. It based on classical scheme first suggested by Blackadar comprises prognostic equations wind components air ground temperature. The main difference from previous works consists in fact that turbulent intensity determined a equation kinetic energy (TKE), rather than using stability functions arbitrarily relate it to atmospheric stability. Results show reproduces condition of connection...
The coexistence of wave‐like submeso motions and anisotropic intermittent turbulence in a night‐time stable boundary layer is investigated. Submeso different characteristics amplitudes interact with each other. These interactions may lead to production which alters the turbulent structure layer. On other hand, transfer affect delicate balance motions. In this work, sonic anemometer data collected at 11 levels southeastern Brazil have been used study case nocturnal coastal site. absence...
Abstract On the basis of measurements over different surfaces, an inertial sublayer (ISL), where Monin‐Obukhov Similarity Theory applies, exists above z =3 h , is canopy height. The roughness within < <3 . Most studies surface layer forests, however, are able to probe only a narrow region Therefore, direct verification ISL tall forests difficult. In this study we conducted systematic analysis unstable turbulence characteristics at heights from 40 325 m, measured 80m, and recently built...
Abstract Oscillations in the horizontal components of wind velocity associated with oscillations air temperature during low–wind speed episodes are ubiquitous stable boundary layer and labeled as meandering. The meandering structure is recognizable by a clear negative lobe Eulerian autocorrelation functions sonic corresponding peak at low frequency spectra. These distinctive features used to isolate occurrences study its properties relation classical description planetary layer. It shown...
Abstract During approximately 80% of its growing season, lowland flooded irrigated rice ecosystems in southern Brazil are kept within a 5–10-cm water layer. These anaerobic conditions have an influence on the partitioning energy and balance components. Furthermore, this cropping system differs substantially from any other upland nonirrigated or crop ecosystems. In study, daily, seasonal, annual dynamics components were analyzed over paddy farm subtropical location using eddy covariance...
Abstract The influence of the cross‐shelf oceanographic front occurring between Brazil Current (BC) and Brazilian Coastal (BCC) on local Marine Atmospheric Boundary Layer (MABL) is investigated here. This typical wintertime in Southern Continental Shelf (SBCS) this first time that its effects are over above MABL. Here we analyze variability, vertical structure, stability MABL as well heat fluxes at air‐sea interface, across five transects SBCS made during a winter 2012 cruise. Local thermal...