Bhattachan Abinash, Okin Gregory S, Zhang Junzhe, Vimal Solomon, Lettenmaier Dennis P
Department of Geography University of California Los Angeles CA USA.
Geohealth. 2019 Oct 28;3(10):328-336. doi: 10.1029/2019GH000212. eCollection 2019 Oct.
Wind is a common ground transportation hazard. In arid regions, wind-blown dust is an added risk. Here, we analyzed the relationship between accidents and wind speed, dust events to study how they may have contributed to vehicular accidents in California. The California Highway Patrol reports information about weather conditions that potentially contributed to traffic accidents, including a code for wind but not for reduced visibility due to dust. For the three counties that contain the major dust source regions in California (the Mojave Desert and the Imperial Valley), we found greater daily maximum wind speed for days with accidents coded for wind compared to all days with accidents. The percentage of people injured in accidents attributed for weather other than wind and coded for wind were the same; however, the percentage of people who died in wind-related accidents was about double the deaths in accidents caused by weather other than wind. At ground meteorological stations closest to accidents, we found lower median minimum visibility for days with wind-related accidents compared to all days with accidents. Across the region, wind speed recorded at ground meteorological stations increased the probability of high satellite-derived dust optical depth values. Over the period of 2006 to 2016, the correlation between daily minimum visibility and daily maximum satellite-estimated dust optical depth was negative. Our analysis of the correlation between dust and accidents shows that with increased wind storm and dust-event frequency in the future, the risk of traffic incidents due to wind and dust could increase.
风是地面交通常见的危害。在干旱地区，风沙是额外的风险因素。在此，我们分析了事故与风速、沙尘事件之间的关系，以研究它们可能如何导致加利福尼亚州的车辆事故。加利福尼亚公路巡逻队报告了可能导致交通事故的天气状况信息，其中包括风的代码，但不包括因沙尘导致能见度降低的代码。对于加利福尼亚州包含主要沙尘源区的三个县（莫哈韦沙漠和帝王谷），我们发现与所有有事故记录的日子相比，因风导致事故的日子里每日最大风速更高。因风以外的天气因素导致事故并被记录为风的事故中受伤人员的百分比相同；然而，与风无关的天气因素导致的事故中的死亡人数相比，因风导致的事故中的死亡人数约为其两倍。在距离事故最近的地面气象站，我们发现与所有有事故记录的日子相比，因风导致事故的日子里最低能见度中位数更低。在整个地区，地面气象站记录的风速增加了卫星衍生的沙尘光学深度高值出现的概率。在2006年至2016年期间，每日最低能见度与每日卫星估计的沙尘光学深度最大值之间的相关性为负。我们对沙尘与事故之间相关性的分析表明，随着未来风暴和沙尘事件频率的增加，因风和沙尘导致交通事故的风险可能会上升。
