【摘要】 76年6月4日甘肃平凉发生一次猛烈雹暴。地面降雹前,等效反射率因子 Ze≥10^4.6mm⁶m（-3）的强回波有二个轴。主轴顶伸展较高,约离地8公里（对应环境温度约-40℃）;次轴顶较低,约离地6公里（环境温度约-25℃）。两个轴在离地3—4公里（-5℃—-10℃）间互相连接。地面收集的雹块经切片分析后得知:雹胚有52％为透明和半透明圆球;雹块内部结构有4—5个层次和1—2个层次的各占45.8 ％和33.6％。由110个雹块的外形得知,扁球、圆球和半圆球形的各占33％、23％和22％。微结构特征说明雹块主要生长在温度较高和扰动较大的过冷却水滴区。更多还原

【Abstract】 A severe hailstorm occurred on 4 June, 1976 in Pingliang region, Gansu province. Before hail shooting on the ground, the intense echo with equivalent reflectivity "factor Ze≥104.6mm6m-3 had, two cores. The top of the main core extended to about 8 Km abeve the ground at -40℃ layer and the top of the other core was lower, about 6 km above the ground at -25℃ layer. The two cores connected with each other at - 5℃--10℃ layer, about 3-4 km above the ground. From the section analysis of hailstones collected on the ground, it was shown that the number of spherical hail embryes which were transparent and semitransperent were 52% of the total embryos. Hailstones with 4-5 and 1-2 internal layers were ,45.8% and 33.6% of the total hailstones collected respectively. Of 110 hailstones collected, the oblate spheroid, spherical and semi-spherical hailstones were 33%, 23% and 22% respectively. The microstructure features of hailstones indicated that they grew mainly in the supercooled-drop region with relatively high temperature and strong disturbance.更多还原