Convective plume concentration fluctuations from a line source in a forest canopy

Convective plume concentration fluctuations from a line source in a forest canopy by Jinfu Liu Download PDF EPUB FB2

An interesting approach is the fluctuating plume model (Gifford, ), which is able to estimate the concentration fluctuations in non-homogeneous turbulence, like in convective or canopy layers Author: Pasquale Franzese.

Micromixing modelling of concentration fluctuations in inhomogeneous turbulence in the convective boundary layer Article in Boundary-Layer Meteorology (1) June with 4 Reads. We describe a comprehensivestudy of the statistical characteristicsof concentration fluctuations in a neutrallybuoyant tracer plume dispersing through a largearray of building-like obstacles, each of whichmeasured m × m × m.

The plumes were released bothupwind and within the obstacle array for a rangeof source heights between and ed flow field and Cited by:   The time-mean and time-varying smoke and velocity structure of a wildfire convective plume is examined using a high-resolution scanning Doppler lidar.

The mean plume is shown to exhibit the archetypal form of a bent-over plume in a crosswind, matching Cited by: 7. This study examines the statistical properties of the concentration derivative, χ′, for a dispersing plume in a near-neutrally stratified atmospheric surface layer.

Towards this goal, the probability density function (pdf) of χ′, and the conditional pdf of χ′ given a fixed concentration level, χ, have been measured. These pdfs are found to be modeled well by a generalizedq-Gaussian Cited by: Representation of convective plumes by vertical adjustment Barry A.

Klinger Oceanographic Center, Nova Southeastern University, Dania, Florida John Marshall Center for Meteorology and Physical Oceanography, Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge Uwe Send.

A closer analysis in Fig. 2, Fig. 3, showing a north–south cross-section of the plumes suggests indeed that the plume dynamics is composed of a sinking in the direction of buoyancy force combined with a stretching along the axis of rotation forming “Taylor ink walls” or “Taylor curtains”.These figures compare well to photos of laboratory experiments by Sheremet () and the Cited by: Forward-in-time and Backward-in-time Dispersion in the Convective Boundary Layer: the Concentration Footprint, Nocturnal C02 Exchange Over a Tall Forest Canopy Associated with Intermittent Low-Level Jet Activity.

Multifractal Analysis of Line-Source Plume Concentration Fluctuations in Surface-Layer Flows. Journal of Applied Meteorology. As the intensity of heating increases (the plume observed at Δ T = 15 K and r 1 = mm, Ra = 10 4 is shown in Fig.

4b), the molecular heat transfer is supplemented with a convective plume. This is called a convective regime. As a result, a convective roll, being concentric with the heat exchanger and having the shape of a torus Cited by: y./ ^ z -' ^ z S where C is the time averaged concentration of pollutant; x, y, and z are the distances downwind, crosswind, and ver- tically upward, respectively; H is the effective s.

urce height above ground level (H is equal to the sum of the physical stack height h and the S plume rise AH); Q is the source strength; 0 is the standard.

P A NUMERICAL STUDY OF NEAR-FIELD DISPERSION WITHIN AND ABOVE FOREST CANOPIES Edburg S.*, Stock D.1, Lamb B.1, Thistle H.2 1Washington State University, Pullman, WA 2 U.S.D.A. Forest Service, Morgantown, WV 1.

ABSTRACT Pheromone releases are used by forest managers as an anti-aggregation technique to protect high. readily measured within the canopy than the source-sink dis-tribution, the problem, commonly termed as the “inverse prob-lem,” reduces to inferring the source-sink distributions from mean concentration profiles [Raupach,a, b].

One of the main difficulties in describing turbulent transport. Model Evaluation, Model Uncertainty, and Concentration Fluctuations. Under support of the American Petroleum Institute, a statistical method for evaluating air quality models was developed and applied to many types of source scenarios, models, and field data sets.

the line connecting the emission source and the observer and the line of sight Vertical angular subtense of plume Concentration of a given species in an air parcel (g m-3) T --Optical thickness of a plume, the line-of-sight integral of the extinction coefficient.

Subscripts refer to the component of the total, or plume, optical thickness (e.g. The funding source for this research is the USDAIUSDI Forest Service National Fire Plan administered through a Research Joint Venture Agreement No.

JV with the Forest Fire Laboratory, Pacific Southwest Research Station, Riverside, by: to structural parameters of a multiple grid-level forest canopy, including tree-cover fraction and clump size.

How fires—in particular, low-intensity fires—perturb the atmosphere in and above a forest canopy within several kilometers of the fire has received little exami-nation and Cited by: 4. Hanna SR. The exponential PDF and concentration fluctuations in smoke plumes. Boundary LayerMeteorology ; Hanna SR.

Concentration fluctuations in a smoke plume. Atmos Environ ; Hanna SR. Atmospheric effects of energy generation. Answers will vary but should include he following ideas: 1. Clear-cutting--all the trees from a designated area are harvested at once 2.

Block cutting--a type of clear-cutting in which al the trees are removed from areas that are acres or less 3. Seed-tree method--all trees except the seed trees are cut 4 Selective-cutting method--mature trees are harvested sporadically. INFLUENCE OF A FOREST CANOPY ON THE NEUTRAL ATMOSPHERIC BOUNDARY LAYER-A LES STUDY B.

Nebenfuhr¨ 1,2 and L. Davidson1,2 1 Div. of Fluid Dynamics, Dept. of Applied Mechanics, Chalmers University of Technology, Gothenburg, Sweden 2 SWPTC, Swedish Wind Power Technology Center [email protected] ETMM 10th International ERCOFTAC Symposium on. times the estimated plume rise above the ocean surface), then the average tracer concentration would have been 50 ppt2, a value well above both the detection limit and normal background levels.

Most of the current world background concentration of. INTRODUCTION. Convective gas flow is the generation of bulk internal gas movement in plants due to humidity- and temperature-induced pressurization of shoot aerenchyma (Armstrong and Armstrong, ; Afreen et al., ).Initially documented in water lilies (Dacey, ), it is now recognized as a widespread flooding tolerance adaptation in both floating-leaved and helophyte species (Brix et Cited by: The large concentration of scatterers in plumes, evident by a plume reflectivity of at least 20 dB above background values, suggests that insects actively oppose updrafts in which they become embedded.

Because the WCR echo is likely mostly due to small insects, this bias should be less than 1 ms Our presentation will validate the WCR.

Parameter Estimation of a Continuous Chemical Plume Source Ajith Gunatilaka 1∗, Branko Ristic2, Alex Skvortsov, Mark Morelande3 1DSTO, HPP Division, Lorimer Street, Fishermans Bend, VicAustralia 2DSTO, ISR Division, Lorimer Street, Fishermans Bend, VicAustralia 3Melbourne Systems Lab, Dept.

EEE, The University of Melbourne, AustraliaCited by: Horizontal dispersion of a near-bed coastal plume isotropic energy spectrum to be E(k)=C φφ2/ 3k−. () In contrast to the three-dimensional case, where the rate of energy transfer between scales is independent of scale, in the two-dimensional case, it is the rate of enstrophy transfer (φ)thatisindependent of the lengthscale of the.

Assuming a plume strength ΔZ = 1 dB, the half-width of echo plume distribution is about one-third of that of interplume regions, that is, the space between the end of one plume and the beginning of the adjacent plume.

The true plume spacing, measured from/to the center of adjacent plumes, is the sum of the interplume spacing and two halves of Cited by: 2. His research showed that this feature of a forest was very strongly related to the habitat value of the forest for birds and that different bird species used forests with different types of canopy structures (e.g., dense subcanopy vs.

tall canopy and open subcanopy) due to needs for nesting, foraging, hunting, etc. Work by my lab and a number Author: Robert Fahey. Soil and canopy CO2, 13CO2, H2O and sensible heat flux partitions in a forest canopy inferred from concentration measurements.

link to publisher version. Statistics; A canopy scale model is presented that utilises Lagrangian dispersal theory to describe the relationship between source distribution and concentration within the by: Project Whitetop--a convective cloud randomized seeding project ;: Ptstatistical analyses of the ground level precipitation data [John A Flueck] on *FREE* shipping on qualifying : John A Flueck.

Temperature Properties of the Inclined Fire Plume above a Circular Fire Source in Cross-Winds Tomohiko Imamura1, Yasushi Oka*2, Osami Sugawa3, Yoshio Takeishi4 and Terushige Ogawa2 1 Graduate School of Engineering, Yokohama National University, Tokiwa dai, Hodogaya-ku, Yokohama, Kanagawa Pref.,Japan.

Evaluation of several measures of canopy openness as predictors of photosynthetic photon flux density in deeply shaded conifer-dominated forest understory José-Luis Machado and Peter B.

Reich Abstract: The ability to accurately estimate light levels in shaded environments is important for understanding plant adaptations to shade. ESTIMATING HEAT SOURCES AND FLUXES IN THERMALLY STRATIFIED CANOPY FLOWS USING HIGHER-ORDER CLOSURE MODELS MARIO SIQUEIRA1,2 and GABRIEL KATUL1,2 1Nicholas School of the Environment and Earth Sciences, Duke University, Durham, BoxNorth CarolinaU.S.A.; 2Civil and Environmental Engineering, Duke University, Durham, North Carolina.

Ma Y, Boybeyi Z, Hanna S and Chayantrakom K. Plume dispersion from the MVP field experiment. Analysis of surface concentration and its fluctuations. Atmos Environ ; Irwin JS and Hanna SR. Characterizing uncertainty in plume dispersion models.

Int J Environ and Poll ; 25 (1/2/3/4): ESTIMATING CANOPY FUEL PARAMETERS IN A PACIFIC NORTHWEST CONIFER FOREST USING MULTIFREQUENCY POLARIMETRIC IFSAR Hans-Erik Andersen a, *, Robert McGaughey b, Stephen Reutebuch b, Gerard Schreuder a, James Ageea, Bryan Mercer c a University of Washingto n, College of Forest Resources, Seattle, WA, USA – (hanserik, gsch, jagee) @ [19] The scalar concentration footprint function (i.e., the downwind concentration distribution of a unit point source (plume) occurring at the origin (x = y = 0, z ≥ 0)) is the product of the crosswind‐integrated concentration footprint, f y in s m −2, and the crosswind distribution function D y in m −1 [Pasquill, ; van Ulden, Cited by: The research network “Basic Concepts for Convection Parameterization in Weather Forecast and Climate Models” was organized with European funding (COST Action ES) for the period of – Its extensive brainstorming suggests how the subgrid-scale parameterization problem in atmospheric modeling, especially for convection, can be examined and developed from the point of view of a Cited by: 8.

THE PLUME EFFECT Repairs to pipe taking effluent far into the ocean offers a chance to examine a release closer to shore. The repair of a massive pipe that carries wastewater to the ocean is inspiring one of the most elaborate scientific investigations in years along the Orange County coast.

Missile-shaped. of a squall line beginning with the formation of scattered clouds in the early morning and concluding with the development of an organized line of deep convective cells. Importantly, the organization of the squall line occurred well within the dual-Doppler coverage area of the S-POL and TOGA radars (see Cifelli et al.

[] and Silva Dias. the three-dimensional circulation around squall lines is primarily generated by the low-frequency component of the latent heating and cooling in the leading convective line.

Past studies of the communication between the lead-ing line and the trailing stratiform region have empha-sized the development of the line-normal circulations. Exercise We wish to determine the emission flux of the hydrocarbon isoprene from a forest canopy.

Measurements from a tower above the canopy indicate mean isoprene concentrations of ppbv at m altitude and ppbv at m altitude.

The turbulent diffusion coefficient is Kz = 1x cm2 s-1 and the air density is x molecules cm distribution inside the canopy, (ii) its evolution during the season and (iii) the variability observed between sites, years and species.

Then, the LMA sub-model is coupled with a process-based model simulating carbon, water and energy balances in forest ecosystem. The coupled model is applied to a sensitive analysis for a case study in a beech.

Models of forest energy, water and carbon cycles assume decreased stomatal conductance with elevated atmospheric CO 2 concentration ([CO 2]) based on leaf-scale measurements, a response not directly translatable to canopies.

Where canopy–atmosphere are well-coupled, [CO 2]-induced structural changes, such as increasing leaf-area index (L D Cited by: The Information Content of a Scalar Plume – a Plume Tracing Perspective QianLiao1 2 DeFrees Hydraulics Laboratory Hollister Hall, Cornell University, Ithaca NY The plume source was a fluorescent dye (fluorescein) with sourceconcentrationC0 =sceinhasaSchmidtnumber.

where the state of acclimation S k (°C) is estimated using a first-order dynamic delay model for X k (°C), which is the a priori estimate for the state of acclimation. It is influenced by the ambient temperature T k (°C) on day k, and its value for the previous day (X k−1). τ is a constant related to the speed of response of the current acclimation status to changes in T by: