采用CM1模式以200 m的高精度水平网格距对一次东北冷涡下的飑线过程进行模拟，采用1 km的水平网格距进行对比试验探究网格距的影响，并通过探空资料的替换与修改研究不稳定能量和垂直风切变对飑线发展的影响。研究表明，水平网格距增大主要使系统演变减缓，强度也有一定的减弱；初始场的不稳定能量减小会使飑线减弱明显，直至无法生成；垂直风切变对飑线的形成影响较小，主要改变了飑线的结构，没有垂直风切变时形成的飑线更为松散。最后的敏感性试验研究了7种云微物理参数方案对飑线内水粒子分布的影响，发现不同的云微物理参数方案会使水粒子的含量和分布出现变化，进一步影响固、液态的降水，飑线模拟采用的NA方案高层冰和雪含量最高，但由于雨和降落到地表的雹、霰含量低，使得累计降水量最小。
The paper adopts the CM1 model to simulate the process of a squall line under the background of Northeast Cold Vortex with a high precision horizontal grid distance of 200 m. Comparative experiment was carried out with a horizontal grid spacing of 1 km to explore the influence of grid spacing on squall line, and the influence of unstable energy and vertical wind shear on the squall line is studied through the replacement and modification of the sounding data. It is found that the increase of horizontal grid spacing mainly slows down the evolution of the system, and the strength of system is also weakened. The decrease of unstable energy of the initial field will cause the squall line to weaken obviously and the squall line can not be generated when the unstable energy is reduced to 0. The vertical wind shear has little effect on the formation of the squall line, which mainly changes the structure of the squall line, and when there is no vertical wind shear in the initial field, the squall line is more loosely in structure. Finally, the sensitivity test studied the influence of seven cloud microphysical parameter schemes on the distribution of water particles in squall line. It is found that different schemes of cloud microphysical parameters will change the content and distribution of water particles and further affect the precipitation of solid and liquid, and lead to different precipitation intensity. The solid water particles of the NASA-Goddard version of LFO (NA) scheme used in the simulation of squall line are mainly snow, and has the highest ice and snow content in the upper layer, however, due to snow and ice did not fall to the surface, and the content of rain, hail and graupel are less than other schemes, the accumulated precipitation is minimal.
[1]Bryan G H, Fritsch J M, 2002. A benchmark simulation for moist nonhydrostatic numerical models[J]. Monthly Weather Review, 130(12):2917-2928.
[2]Dahl J M L, 2017. Tilting of horizontal shear vorticity and the development of updraft rotation in supercell thunderstorms[J]. Journal of the Atmospheric Sciences, 74(9):2997-3020.
[3]Diao M, Bryan G H, Morrison H, et al, 2017. Ice nucleation parameterization and relative humidity distribution in idealized squall-line simulations[J]. Journal of the Atmospheric Sciences, 74(9):2761-2787.
[4]Evans J S, Doswell Ⅲ C A, 2001. Examination of derecho environments using proximity soundings[J]. Weather and Forecasting, 16(3):329-342.
[5]Gilmore M S, Straka J M, Rasmussen E N, 2004. Precipitation and evolution sensitivity in simulated deep convective storms:Comparisons between liquid-only and simple ice and liquid phase microphysics[J]. Monthly Weather Review, 132(8):1897-1916.
[6]Guarriello F, Nowotarski C J, Epifanio C C, 2018. Effects of the low-level wind profile on outflow position and near-surface vertical vorticity in simulated supercell thunderstorms[J]. Journal of the Atmospheric Sciences, 75(3):731-753.
[7]Hane C E, 1973. The squall line thunderstorm:Numerical experimentation[J]. Journal of the Atmospheric Sciences, 30(8):1672-1690.
[8]Lafore J, Moncrieff M W, 1989. A numerical investigation of the organization and interaction of the convective and stratiform regions of tropical squall lines[J]. Journal of the Atmospheric Sciences, 46(4):521-544.
[9]Liu C, Moncrieff M W, Zipser E J, 1997. Dynamical influence f microphysics in tropical squall lines:A numerical study[J]. Monthly Weather Review, 125(9):2193-2210.
[10]Lombardo K, Kading T, 2018. The behavior of squall lines in horizontally heterogeneous coastal environments[J]. Journal of the Atmospheric Sciences, 75(4):1243-1269.
[11]Parker M D, 2017. How much does "Backing Aloft" actually impact a supercell?[J]. Weather and Forecasting, 32(5):1937-1957.
[12]Takemi T, 2006. Impacts of moisture profile on the evolution and organization of midlatitude squall lines under various shear conditions[J]. Atmospheric Research, 82(1):37-54.
[13]Takemi T, 2007. A sensitivity of squall-line intensity to environmental static stability under various shear and moisture conditions[J]. Atmospheric research, 84(4):374-389.
[14]Weisman M L, Rotunno R, 1925. "A theory for strong long-lived squall lines" revisited[J]. Journal of the Atmospheric Sciences, 45(3):463-485.
[15]Weisman M L, Klemp J B, Rotunno R, 1988. Structure and evolution of numerically simulated squall lines[J]. Journal of the Atmospheric Sciences, 45(14):1990-2013.
[16]Weisman M L, 1992. The role of convectively generated rear-inflow jets in the evolution of long-lived mesoconvective systems[J]. Journal of the Atmospheric Sciences, 49(19):1826-1847.
[17]曹倩, 张述文, 曹帮军, 等, 2016.超强不稳定和弱切变环境下一次飑线过程的雷达资料同化与分析[J].热带气象学报, 32(5):645-655.
[18]刁秀广, 孟宪贵, 万明波, 等, 2015.源于飑线前期和强降雨带后期的弓形回波雷达产品特征及预警[J].高原气象, 34(5):1486-1494. DOI:10.7522/j.issn.1000-0534.2014.00097.
[19]丁治英, 夏蘩, 高松, 等, 2017.一次飑线过程中雷达回波的组织结构变化及成因分析[J].热带气象学报, 33(3):323-333.
[20]康延臻, 靳双龙, 彭新东, 等, 2018.单双参云微物理方案对华北"7·20"特大暴雨数值模拟对比分析[J].高原气象, 37(2):481-494. DOI:10.7522/j.issn.1000-0534.2017.00026.
[21]康兆萍, 林永辉, 2017.华南一次飑线过程线状对流模态变异机理研究[J].大气科学学报, 40(5):631-640.
[22]李哲, 李国翠, 刘黎平, 等, 2017.飑线优化识别及雷暴大风分析[J].高原气象, 36(3):801-810. DOI:10.7522/j.issn.1000-0534.2016.00040.
[23]栾澜, 孟宪红, 吕世华, 等, 2017.青藏高原一次对流降水模拟中边界层参数化和云微物理的影响研究[J].高原气象, 36(2):283-293. DOI:10.7522/j.issn.1000-0534.2016.00086.
[24]梅海霞, 沈新勇, 王卫国, 等, 2015.双参数微物理方案在WRF单柱模式中的模拟检验和对比研究[J].高原气象, 34(4):890-909. DOI:10.7522/j.issn.1000-0534.2014.00113.
[25]王洪, 尹金方, 王东海, 2014.单双参云微物理方案对华南暴雨的模拟对比分析[J].高原气象, 33(5):1341-1351. DOI:DOI:10.7522/j.issn.1000-0534.2013.00119.
[26]王田田, 高晓清, 尹宪志, 等, 2016. WRF模式物理过程参数化方案对酒泉地区暴雨模拟的影响[J].高原气象, 35(5):1257-1269. DOI:10.7522/j.issn.1000-0534.2015.00096.
[27]赵桂香, 薄燕青, 邱贵强, 等, 2017.黄河中游一次大暴雨的观测分析与数值模拟[J].高原气象, 36(2):436-454. DOI:10.7522/j.issn.1000-0534.2016.00093.
[28]郑媛媛, 张雪晨, 朱红芳, 等, 2014.东北冷涡对江淮飑线生成的影响研究[J].高原气象, 33(1):261-269. DOI:10.7522/j.issn.1000-0534.2013.00005.
