Plume tracing

Weather Effects When following plumes to a source, weather can be a major factor. Obviously, this applies in water as well as in air. When turbulence is heavy, the plume will become more dispersed. This turbulence can result from a temporary, weather-induced condition, but may force delay in plume tracing. Judging the degree of turbulence in water is somewhat easier than in air, simply because we can see the water. 

Accurate description of mixing processes on each of these scales is only possible in a few selected and idealized cases. One of the best understood cases is that of a turbulent PBL over flat terrain and a point source of a trace substance. In this case, the concentration downwind of the source is often described as a plume. Figure 7-3 shows such an idealized plume. 

Minster JF, Allegre CJ (1978) Systemahc use of trace elements in igneous processes. Part III Inverse problem of batch melting in volcanic suites. Contrib Mineral Pehol 68 37-52 Morgan JW (1971) Convechon plumes in the lower manhe. Nature 230 42-43... 

Trace organic compounds and dissolved solids from the quench water entrained in the steam plume rising from the tower... 

Examples of the need for multimedia models are found in contemporary problem areas. Polynuclear aromatic hydrocarbons and metals are emitted into the atmosphere as trace impurities with the products of coal combustion. The organics have low vapor pressure and partially condense on emitted particulates in a stack plume. The particulates are transferred to the soil by dry deposition, rainout or washout. The metals manifest... 

Cosson, R.P, C. Amiard-Triquet, and J.C. Amiard. 1988a. Utilisation des plumes dans le recherche des sources de contamination des oiseaux par les elements traces Cd, Cu, Hg, Pb, Se, et Zn chez les flamants de Camargue, France. Water Air Soil Pollut. 42 103-115. 

In addition to observations in Los Angeles, Blumenthal and White have reported measurements of a power-plant plume and an urban plume 35 and 46 km downwind from St. Louis, Nfissouri. Bgute 4-25 shows the evidence of extensive ozone buildup in the urban plume. Simultaneous measurements of scattering coefficient, 6>cat, trace the spread and dilution of suspended particulate material. It is interesting that in the urban plume, which spreads to 20 km in width, the ozone increases while the particulate matter decreases this suggests considerable photochemical production at an altitude of 750 m. Contrary to the statements of Davis and co-workers reported above, the power-plant plume causes a decrease, rather than an increase, in ozone. Nitric oxide in the plume reacts with the ozone as it mixes. This is clearly indicated by the distribution of particulate matter, which acts as a tracer. 

Davis, D. D., G. Smith, and G. Klauber. Trace gas analysis of power plant plumes via aircraft measurement O3, NO, and SO] Chemistry. Science 186 733-736, 1974. 

A. Hayden, E. Niple, and B. Boyce, Determination of trace-gas amounts in plumes by the use of orthogonal digital filtering of thermal emission spectra, Appl. Opt., 35(16), 2802-2809 (1996). 

The trace element patterns in Figure 4 are similar to komatiites of the Kidd-Munro assemblage, whose negative HFSE were interpreted by %man (1999) to be a result of contamination by other HFSE-depleted rock. If Big Lake volcanic rocks are plume-derived, their negative HFSE depletions could similarly be explained by country arc rock contamination in lavas or parent magma chambers. 

A second example is shown in excerpt 13Q. Harpp s proposed work initially involves the collection of held data in two sampling campaigns. Following collection, the samples will be analyzed for trace and major element concentrations and isotopic ratios. In her case, the order in which she conducts these analyses is less important than how she will use the data to answer questions about plume-ridge interaction mechanisms. Thus, she organizes her proposed work (titled Proposed Plan ) not by the tests she will perform, but rather by the types of information the analyzed data will provide (i.e., information about formation mechanisms, melting dynamics, and spatial distributions). 

Year Five Complete analysis of trace elements by ICP-MS at Lawrence University analysis of major elements by XRF at Macalester College (up to 100 samples) determination of Sr, Nd, and Pb isotopic ratios of a selection of Wolf and Darwin samples by TIMS at Cornell (up to 30 samples). Interpretation of geochemical data, modeling of melting parameters. Presentation of results at Fall AGU meeting by undergraduate student(s). Preparation of final plume-ridge interaction synthesis paper for publication with student authors. 

A much-simplified classification, based on these tables, is shown in Table 4.6. The scale of interest is very different for trace chemical or odor plumes from that for which the original classification system was developed. Therefore, it is proposed that the simplified classification scheme of Table 4.6 will be sufficiently applicable to provide an indication of the more and the less favorable conditions for following plumes. In this presentation the lighter shading denotes those conditions that are generally more favorable darker shading indicates more instability and hence less well defined plumes. 

Several types of computer models have been developed for estimating the expected concentrations of the chemicals of interest as they move away from the source. Soil transport models attempt to estimate the expected concentration at the surface above buried sources. Plume transport models attempt to estimate the concentrations within a plume, along with its shape and position. A different form of model is designed to guide a search pattern for employing a sensing system to trace a plume. 

Another piece of evidence for anthropogenic emissions leading to increased CCN and hence effects on cloud properties such as albedo and extent is found in ship tracks. These are lines of clouds that trace ship movements, either in initially cloud-free regions (Conover, 1966 Platnick and Twomey et al., 1994) or superimposed on preexisting clouds (Coakley et al., 1987). Emissions associated with the ship exhausts serve as CCN. This allows clouds to form where the background CCN concentration is too small for cloud formation. Alternatively, the CCN can modify existing cloud properties in the exhaust plume by changing the number and size distribution of the cloud droplets as well as the liquid water content (e.g., Ferek et al., 1998). 

Carras, J. N. 1995. The transport and dispersion of plumes from tall stacks. In Swaine, D. J. Goodarzi, F. (eds) Environmental Aspects of Trace Elements in Coal. Kluwer Academic Publishers, Dordrecht, 146-177. 

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