原标题：唠"科"话丨这轮广东的雨为啥这么大？ 新华社广州8月7日电（记者田宇、胡拿云）这几天，广东出现大范围强降雨过程，让人感觉"雨下 个没完"。广东省防汛防旱防风总指挥部从3日至5日连续将防汛应急响应从Ⅳ级调整至Ⅱ级。国家防减 救灾委6日对广东启动国家四级救灾应急响应。在广州、肇庆、清远等地，出现内涝、树木倾倒、甚至 发生山洪、道路塌陷。广东这轮降雨为何下得如此猛烈？它又将持续到何时？ 这轮降雨强度为何这么大？ 要解析这轮强降雨的成因，不妨先从降雨的基本原理说起。简单来讲，形成降雨需要三个核心条 件：一是"动力抬升机制"，二是"充足的水汽"，三是"较多的凝结核"——空气中悬浮的尘埃、烟尘等微 粒，能让水汽更易附着、聚集，进而形成云层。具体可以这样理解：当含有大量水汽的湿润空气快速上 升时，由于高空温度较低，水汽会因降温而凝结成雨滴，最终落到地面形成降雨。 要解开广东本轮强降雨的成因，不妨聚焦几个关键的气象"推手"： 首先是抬升机制源于低涡。它和台风很像，甚至可以形容为"在陆地上的台风"。低涡生成于陆地， 一般覆盖范围在200公里至2000公里以内，而台风生成于海上，通常覆盖范围在2000公里以上。在北半 球 ...

Core Insights - The strongest rainfall since the onset of the flood season has affected 14 provinces and regions in southern China from June 17 to 23, with many areas breaking historical daily rainfall records [1][2] - The cumulative rainfall in provinces such as Guangxi, Guizhou, Hunan, Hubei, and Anhui reached between 400 to 700 millimeters, with some localities exceeding 1,118 millimeters [2][3] - A new round of strong rainfall is expected to follow immediately, impacting areas including Sichuan and Chongqing, although the intensity and range will be less than the previous event [4][6] Rainfall Data - Specific extreme rainfall records include: - Hubei Hefeng: 328.4 mm on June 19 - Guizhou Zhijin: 279.7 mm on June 19 - Guangxi Tian'e: 208.7 mm on June 23 - Hunan Longshan: 205.8 mm on June 19 - Jiangsu Hongze: 191 mm on June 20 - Jiangsu Binhai: 189 mm on June 20 [3] Meteorological Analysis - The intensity of the rainfall is attributed to favorable conditions for moisture and energy, with the positioning of the subtropical high-pressure system causing persistent rainfall in the Yangtze River region [3] - The interaction of cold and warm air masses at the edge of the subtropical high-pressure system has led to prolonged heavy rainfall, with both cold vortices and subtropical high-pressure being stronger than usual [3] Upcoming Weather Forecast - From now until June 27, another round of strong rainfall is anticipated, particularly affecting the eastern part of the southwest region and areas like Jianghan and Huanghuai [4][6] - The core impact period for this new rainfall event is expected to be tomorrow and the day after, with significant rainfall predicted for regions from Guizhou to southern Henan [6] - Areas previously affected by heavy rainfall may experience cumulative rainfall exceeding 200 millimeters, raising concerns about potential secondary disasters such as landslides and mudslides due to saturated soil conditions [4][6]