Hughes Jonathan E, Kaffine Daniel, Kaffine Leah
Department of Economics and Renewable and Sustainable Energy Institute, University of Colorado at Boulder, Boulder, CO.
Independent Researcher.
Transp Res Rec. 2023 Apr;2677(4):892-903. doi: 10.1177/03611981221103239. Epub 2022 Jun 23.
Highway fatalities are a leading cause of death in the U.S. and other industrialized countries. Using highly detailed crash, speed, and flow data, we show highway travel and motor vehicle crashes fell substantially in California during the response to the COVID-19 pandemic. However, we also show the frequency of severe crashes increased owing to lower traffic congestion and higher highway speeds. This "speed effect" is largest in counties with high pre-existing levels of congestion, and we show it partially or completely offsets the "VMT effect" of reduced vehicle miles traveled on total fatalities. During the first eleven weeks of the COVID-19 response, highway driving decreased by approximately 22% and total crashes decreased by 49%. While average speeds increased by a modest 2 to 3 mph across the state, they increased between 10 and 15 mph in several counties. The proportion of severe crashes increased nearly 5 percentage points, or 25%. While fatalities decreased initially following restrictions, increased speeds mitigated the effect of lower vehicle miles traveled on fatalities, yielding little to no reduction in fatalities later in the COVID period.
在美国和其他工业化国家，高速公路交通事故是主要的死亡原因之一。利用高度详细的碰撞、速度和流量数据，我们发现，在应对新冠疫情期间，加利福尼亚州的高速公路出行和机动车碰撞事故大幅下降。然而，我们也发现，由于交通拥堵减少和高速公路速度提高，严重碰撞事故的频率有所增加。这种“速度效应”在拥堵程度较高的县最为明显，我们还发现，它部分或完全抵消了行驶里程减少对总死亡人数的“车辆行驶里程效应”。在应对新冠疫情的前11周，高速公路驾驶量下降了约22%，总碰撞事故下降了49%。虽然全州平均速度适度提高了2至3英里/小时，但在几个县，平均速度提高了10至15英里/小时。严重碰撞事故的比例增加了近5个百分点，即25%。虽然在实施限制措施后死亡人数最初有所下降，但速度的提高减轻了行驶里程减少对死亡人数的影响，在新冠疫情后期，死亡人数几乎没有减少甚至没有减少。
