新闻分析：影响18省份，北方沙尘为何一直吹到海南岛？

Core Viewpoint - The recent sandstorm has affected 18 provinces in China, marking one of the most extensive sandstorm events in recent years, with the dust reaching as far south as Hainan Island [1][2]. Group 1: Weather Impact - The Central Meteorological Observatory issued a blue warning for sandstorms, predicting dust and floating dust weather from April 13 to April 14 across multiple provinces including Xinjiang, Inner Mongolia, and Guangdong [2][3]. - The sandstorm has led to reduced visibility and deteriorating air quality, adversely affecting transportation and public health [5]. Group 2: Causes of the Sandstorm - Three main factors contributed to the widespread sandstorm: extreme winds leading to high intensity of dust, high altitude of dust transport allowing rapid movement, and early cessation of rainfall in southern regions which reduced the settling effect of precipitation [4]. Group 3: Duration of the Sandstorm - The Central Meteorological Observatory has issued an orange warning for strong winds, indicating that many areas in the north will continue to experience winds of 5 to 7 levels, with gusts reaching 8 to 10 levels [6]. - Dust conditions in southern regions are expected to persist until the morning of April 14, with recommendations for the public to minimize outdoor activities and take protective measures [7].