Radar polarimetric signatures of fire plumes in Oklahoma

Melnikov, Valery; Zrnić, Dúsan S.; Rabin, Robert M.; Zhang, P.

doi:10.1029/2008gl034311

Cited by 50 publications

(69 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Three elevation angles are inspected (0.5, 1.5, and 2.4 • ), intersecting the updraft core at heights of 4115, 7742, and 11 009 m, respectively. The lowest scan shows very high Z dr , indicative of large, horizontally oriented particles, which is consistent with ash (Melnikov et al, 2008(Melnikov et al, , 2009Lang et al, 2014) (Fig. 8a).…”

Section: Radar Analysissupporting

confidence: 61%

“…Z dr is the logarithmic ratio of the reflectivity from the horizontally and vertically polarized radar beams (Markowski and Richardson, 2011). When Z dr is large and positive it indicates the presence of large horizontal targets, including needle-like ash particles (Melnikov et al, 2008(Melnikov et al, , 2009. When Z dr is near zero the targets are more spherical (e.g., hydrometeors), and when negative the targets are vertically oriented (e.g., graupel).…”

Section: Radar Datamentioning

confidence: 99%

“…Radars have been used in numerous wildfires studies (Banta et al, 1992;Hufford et al, 1998;Fromm et al, 2006;Rosenfeld et al, 2007;Jones and Christopher, 2010a, b). Recently, dual-polarization radars have been used to examine the microphysics of wildfire plumes and clouds (Melnikov et al, 2008(Melnikov et al, , 2009Lang et al, 2014).…”

Section: Radar Datamentioning

confidence: 99%

See 2 more Smart Citations

Environmental controls on pyrocumulus and pyrocumulonimbus initiation and development

Lareau

Clements

2016

Atmos. Chem. Phys.

View full text Add to dashboard Cite

Abstract. In this paper we present the first direct observational evidence that the condensation level in pyrocumulus and pyrocumulonimbus clouds can be significantly higher than the ambient lifted condensation level. In addition, we show that the environmental thermodynamic profile, day-today variations in humidity, and ambient wind shear all exert significant influence over the onset and development of pyroconvective clouds. These findings are established using a scanning Doppler lidar and mobile radiosonde system during two large wildfires in northern California, the Bald Fire and the Rocky Fire. The lidar is used to distinguish liquid water from smoke backscatter during the plume rise, and thus provides a direct detection of plume condensations levels. Plume tops are subsequently determined from both the lidar and nearby radar observations. The radiosonde data, obtained adjacent to the fires, contextualize the lidar and radar observations, and enable estimates of the plume ascent, convective available potential energy, and equilibrium level. A noteworthy finding is that in these cases, the convective condensation level, not the lifted condensation level, provides the best estimate of the pyrocumulus initiation height.

show abstract

Section: Radar Analysissupporting

confidence: 61%

Section: Radar Datamentioning

confidence: 99%

See 1 more Smart Citation

Environmental controls on pyrocumulus and pyrocumulonimbus initiation and development

Lareau

Clements

2016

Atmos. Chem. Phys.

View full text Add to dashboard Cite

show abstract

“…He also stated that similar observations have been reported as early as 1950. The WSR-88D weather radar network in the US, for example, has consistently observed nearby forest fire activity in Florida and Texas [13], [14]. While these radars are more sensitive than small-scale systems, their large separation means that they often view the smoke plume from fires at high altitudes above Even today, bushfires still remain an ever-present threat.…”

Section: Bushfire Monitoringmentioning

confidence: 97%

Weather and bushfire observation using low cost X-band phased array radars

Palumbo

Al-Ashwal

Ferguson

et al. 2013

2013 International Conference on Radar

View full text Add to dashboard Cite

Small-scale, low-cost X-band radars are an emerging technology that offer signficant advantages over traditional largescale systems for weather and remote sensing applications. Xband radars provide enhanced angular resolution at a fraction of the aperture size compared to larger, lower frequency systems. Because of their low cost and small form factor, these radars can now be integrated into more research and commercial applications. This paper presents the research activities currently underway using a low-cost, X-band (9.41 GHz) Phase-Tilt Radar. The "phase-tilt" design is a novel architecture that allows for rapid electronic scanning in azimuth and mechanical tilting in elevation, as a compromise between cost and performance. This paper presents the relevant background information on the technology, as well as some initial studies and field work on the research activities performed.

show abstract

“…Although a reasonable performance of the plume models has been demonstrated for selected case studies on local or regional scales, the knowledge about smoke plume heights on a global scale is very limited due to a lack of observational data sets. Besides a small number of airborne in situ and ground-based remote-sensing studies, e.g., Melnikov et al (2008) or Liu et al (2013), satellite data sets provide observations of potentially global coverage. Although smoke plume measurement uncertainties are only ±200 m for well-constrained plumes Nelson et al, 2013), only a limited number of plumes are available on the global scale, because a partly manual analysis is required for each individual plume.…”

Section: Introductionmentioning

confidence: 99%

Fire emission heights in the climate system – Part 1: Global plume height patterns simulated by ECHAM6-HAM2

et al. 2015

View full text Add to dashboard Cite

Abstract. We use the global circulation model ECHAM6 extended by the aerosol module HAM2 to simulate global patterns in wildfire emission heights. Prescribed plume heights in ECHAM6 are replaced by an implementation of a simple, semi-empirical plume height parametrization. In a first step, the global performance of the plume height parametrization is evaluated for plumes reported in the Multiangle Imaging Spectroradiometer (MISR) Plume Height Project (MPHP) data set. Our results show that the parametrization simulates a largely reasonable global distribution of plume heights. While the modeled global mean plume height (1411±646 m) is in good agreement with the observed mean (1382±702 m), the upper and lower tails of the plume height distribution tend to be slightly underrepresented. Furthermore, we compare plume heights simulated by the simple parametrization to a more complex, analytical plume model. Major differences in global plume height distributions are found for the lowest 1.5 km, but reasonable agreement is observed for higher plumes. In a second step, fire radiative power (FRP) as reported in the global fire assimilation system (GFAS) is used to simulate plume heights for observed fires globally for the period 2005-2011. The global fraction of simulated daytime plumes injecting emissions into the free troposphere (FT) ranges from 3.7 ± 0.7 to 5.2 ± 1.0 %. This range is comparable to results from observational studies, but it is much lower than results for prescribed plume heights in the ECHAM6-HAM2 standard setup. Nevertheless, occasionally deep emission injections exceeding 5-7 km in height are simulated for intense fires and favorable meteorological conditions. The application of a prescribed diurnal cycle in FRP turns out to be of minor importance. For a hypothetical doubling in FRP, moderate changes in plume heights of 100-400 m are simulated. These small changes indicate that a potential future increase in fire intensity will only slightly impact the emission heights on a global scale.

show abstract

Radar polarimetric signatures of fire plumes in Oklahoma

Cited by 50 publications

References 13 publications

Environmental controls on pyrocumulus and pyrocumulonimbus initiation and development

Environmental controls on pyrocumulus and pyrocumulonimbus initiation and development

Weather and bushfire observation using low cost X-band phased array radars

Fire emission heights in the climate system – Part 1: Global plume height patterns simulated by ECHAM6-HAM2

Contact Info

Product

Resources

About