Global S&T Development Trend Analysis Platform of Resources and Environment
DOI | 10.1175/JAS-D-19-0316.1 |
Are Supercells Resistant to Entrainment because of Their Rotation? | |
Peters, John M.1; Nowotarski, Christopher J.2; Mullendore, Gretchen L.3 | |
2020-04-01 | |
发表期刊 | JOURNAL OF THE ATMOSPHERIC SCIENCES |
ISSN | 0022-4928 |
EISSN | 1520-0469 |
出版年 | 2020 |
卷号 | 77期号:4页码:1475-1495 |
文章类型 | Article |
语种 | 英语 |
国家 | USA |
英文摘要 | This research investigates a hypothesis posed by previous authors, which argues that the helical nature of the flow in supercell updrafts makes them more resistant to entrainment than nonsupercellular updrafts because of the suppressed turbulence in purely helical flows. It was further supposed that this entrainment resistance contributes to the steadiness and longevity of supercell updrafts. A series of idealized large-eddy simulations were run to address this idea, wherein the deep-layer shear and hodograph shape were varied, resulting in supercells in the strongly sheared runs, nonsupercells in the weakly sheared runs, and variations in the percentage of streamwise vorticity in updrafts among runs. Fourier energy spectrum analyses show well-developed inertial subranges in all simulations, which suggests that the percentages of streamwise and crosswise vorticity have little effect on turbulence in convective environments. Additional analyses find little evidence of updraft-scale centrifugally stable flow within updrafts, which has also been hypothesized to limit horizontal mass flux across supercell updrafts. Results suggest that supercells do have smaller fractional entrainment rates than nonsupercells, but these differences are consistent with theoretical dependencies of entrainment on updraft width, and with supercells being wider than nonsupercells. Thus, while supercells do experience reduced fractional entrainment rates and entrainment-driven dilution, this advantage is primarily attributable to increased supercell updraft width relative to ordinary convection, and has little to do with updraft helicity and rotation. |
英文关键词 | Clouds Convective storms systems Updrafts downdrafts Severe storms Storm environments |
领域 | 地球科学 |
收录类别 | SCI-E |
WOS记录号 | WOS:000528754800013 |
WOS关键词 | VERTICAL WIND SHEAR ; SIMULATED CONVECTIVE STORMS ; HIGH-RESOLUTION SIMULATION ; SHALLOW ; HELICITY ; THUNDERSTORM ; PROPAGATION ; EXPRESSIONS ; TRANSITION ; VORTICITY |
WOS类目 | Meteorology & Atmospheric Sciences |
WOS研究方向 | Meteorology & Atmospheric Sciences |
引用统计 | |
文献类型 | 期刊论文 |
条目标识符 | http://119.78.100.173/C666/handle/2XK7JSWQ/280326 |
专题 | 地球科学 |
作者单位 | 1.Naval Postgrad Sch, Dept Meteorol, Monterey, CA 93943 USA; 2.Texas A&M Univ, Dept Atmospher Sci, College Stn, TX USA; 3.Univ North Dakota, Dept Atmospher Sci, Grand Forks, ND USA |
推荐引用方式 GB/T 7714 | Peters, John M.,Nowotarski, Christopher J.,Mullendore, Gretchen L.. Are Supercells Resistant to Entrainment because of Their Rotation?[J]. JOURNAL OF THE ATMOSPHERIC SCIENCES,2020,77(4):1475-1495. |
APA | Peters, John M.,Nowotarski, Christopher J.,&Mullendore, Gretchen L..(2020).Are Supercells Resistant to Entrainment because of Their Rotation?.JOURNAL OF THE ATMOSPHERIC SCIENCES,77(4),1475-1495. |
MLA | Peters, John M.,et al."Are Supercells Resistant to Entrainment because of Their Rotation?".JOURNAL OF THE ATMOSPHERIC SCIENCES 77.4(2020):1475-1495. |
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