Plume

Plume
Name	Plume
Classification	Physical phenomenon
Related	Aerosol, Jet, Wake, Plume model, Smoke plume

Plume A plume is a coherent, often buoyant, column or sheet of fluid, particulate, or gas that rises, spreads, or advects into a surrounding medium, producing distinctive flow, transport, and visual patterns. Plumes occur across planetary atmospheres, oceans, and industrial contexts, spanning phenomena observed with instruments used by entities such as NASA, NOAA, European Space Agency, US Geological Survey, and United States Environmental Protection Agency. Studies of plumes draw on methods and concepts developed at institutions like MIT, Caltech, Imperial College London, Scripps Institution of Oceanography, and Woods Hole Oceanographic Institution.

Etymology and Definitions

The term derives from Old French plume, meaning "feather", with usage extending into scientific literature in works by figures associated with Royal Society publications and early investigators such as Isaac Newton and Benjamin Franklin where analogies to feather-like shapes described smoke and vapor. In fluid dynamics and environmental science, formal definitions appear in texts by researchers at Princeton University, University of Cambridge, and California Institute of Technology, distinguishing plumes from jets, wakes, and fountains in treatises referenced in conferences like the American Geophysical Union and journals such as Nature, Science, and Journal of Fluid Mechanics.

Types and Characteristics

Common categories include thermal plumes, buoyant plumes, forced plumes, passive tracers, volcanic plumes, hydrothermal plumes, smoke plumes, and pollutant plumes. Thermal plumes such as those studied in experiments at Argonne National Laboratory or Los Alamos National Laboratory are driven by heat sources like furnaces, combustion chambers, or geothermal vents. Volcanic plumes are typified by eruptions at Mount St. Helens, Krakatoa, Eyjafjallajökull, and Mount Pinatubo and contain ash, aerosols, and gases including sulfur dioxide measured by missions like Aura (satellite) and instruments from European Space Agency platforms. Hydrothermal plumes found at ridge systems such as the Mid-Atlantic Ridge, East Pacific Rise, and Juan de Fuca Ridge carry mineral-laden fluids that support ecosystems documented by teams from NOAA Pacific Marine Environmental Laboratory and Monterey Bay Aquarium Research Institute. Characteristics used to classify plumes include buoyancy flux, momentum flux, entrainment rate, Richardson number, Reynolds number, Froude number, and Richardson–Obukhov scaling, with canonical profiles reported in handbooks from Cambridge University Press and software developed at NCAR and LAMMPS communities.

Formation and Dynamics

Plume formation can follow sudden injection, continuous release, buoyant ascent, or forced jet interaction. Mechanisms involve turbulent entrainment, shear layer development, stratification effects, and mixing processes analyzed in experimental work at University of Oxford, ETH Zurich, and Princeton. Atmospheric plume dynamics couple to synoptic flows influenced by systems like El Niño–Southern Oscillation, North Atlantic Oscillation, and mesoscale convective complexes studied by National Center for Atmospheric Research and meteorological services such as Met Office and Japan Meteorological Agency. Oceanic plume dynamics interact with currents like the Gulf Stream, Kuroshio Current, and internal waves observed by arrays managed by Argo (oceanography), NOAA Fisheries, and research vessels such as RV Atlantis. Volcanic plumes involve ballistic fallout, umbrella clouds, and column collapse linked to eruption styles categorized by the Volcanic Explosivity Index and case studies at Mount Vesuvius and Kīlauea. Dispersion models such as Gaussian plume models, Lagrangian particle models, and computational fluid dynamics implementations in codes from ANSYS and OpenFOAM quantify spreading and entrainment.

Ecological and Environmental Impacts

Plumes transport heat, nutrients, contaminants, and biota, producing ecological consequences documented in regions like the Gulf of Mexico, Baltic Sea, Great Barrier Reef, and Amazon Basin. Hydrothermal plumes support chemosynthetic communities including species described by researchers at Scripps Institution of Oceanography and Smithsonian Institution collections. Pollutant plumes from industrial sources and oil spills (e.g., Deepwater Horizon) affect fisheries regulated by agencies such as NOAA Fisheries and conservation organizations like WWF and Greenpeace. Volcanic plumes influence climate through stratospheric aerosol injection, with historic events at Mount Tambora and Mount Pinatubo linked to radiative forcing studied by groups at IPCC and Lawrence Berkeley National Laboratory. Urban heat and smoke plumes impact air quality monitored by networks including AirNow and European Environment Agency.

Human Uses and Cultural Significance

Humans harness plume phenomena in technologies and cultural practices. Chimney plumes and exhaust stacks engineered by firms like Siemens and General Electric manage combustion products, while controlled plumes power propulsion in SpaceX and Blue Origin launches observed at centers such as Kennedy Space Center and Vandenberg Space Force Base. Thermal plumes underpin passive cooling designs in buildings by architects collaborating with ASHRAE standards and projects at The Edge (Amsterdam). In cultural contexts, smoke plumes play roles in rituals and ceremonies across societies including examples from Maori culture, Navajo Nation, and practices documented by UNESCO in intangible heritage inventories. Artistic depictions of plumes appear in works by painters referenced in museums like the Tate Modern, Louvre, and Museum of Modern Art.

Detection, Monitoring, and Measurement

Detection employs remote sensing, in situ sampling, and numerical inversion. Satellite instruments such as MODIS, OMI, CALIPSO, and Sentinel-5P detect aerosol optical depth and gas columns, while airborne platforms operated by NASA and research institutes deploy lidar, radar, and mass spectrometers. Oceanographic plumes are traced with CTD casts, plume tracers, and autonomous vehicles from institutions like WHOI and MBARI. Ground networks including AirNow, Eionet, and national monitoring programs use sensors calibrated against standards established by NIST and measurement protocols in journals like Environmental Science & Technology. Model-data integration leverages assimilation systems at ECMWF and ensemble forecasts developed by NOAA Global Forecast System to support emergency response by agencies such as Federal Emergency Management Agency and international coordination through ICAO for aviation hazards.

Category:Fluid dynamics