CICERO (Center for International Climate and Environmental Research-Oslo) P.O. Box 1129, Blindern, N-0318 Oslo, Norway.
Environ Sci Technol. 2012 May 1;46(9):5205-13. doi: 10.1021/es204190w. Epub 2012 Apr 10.
Passenger transport affects climate through various mechanisms involving both long-lived and short-lived climate forcers. Because diesel cars generally emit less CO(2) than gasoline cars, CO(2) emission taxes for vehicle registrations and fuels enhance the consumer preference for diesel cars over gasoline cars. However, with the non-CO(2) components, which have been changed and will be changed under the previous and upcoming vehicle emission standards, what does the shift from gasoline to diesel cars mean for the climate mitigation? By using a simple climate model, we demonstrate that, under the earlier emissions standards (EURO 3 and 4), a diesel car causes a larger warming up to a decade after the emissions than a similar gasoline car due to the higher emissions of black carbon and NO(X) (enhancing the O(3) production). Beyond a decade, the warming caused by a diesel car becomes, however, weaker because of the lower CO(2) emissions. As the latter emissions standards (EURO 5 and 6) are phased in, the short-term warming due to a diesel car becomes smaller primarily due to the lower black carbon emissions. Thus, although results are subject to restrictive assumptions and uncertainties, the switch from gasoline to diesel cars encouraged by CO(2) taxes does not contradict with the climate mitigation focusing on long-term consequences.
客运通过涉及长寿命和短寿命气候强迫物的各种机制影响气候。由于柴油车通常比汽油车排放更少的二氧化碳，因此车辆注册和燃料的二氧化碳排放税增强了消费者对柴油车的偏好而不是汽油车。然而，随着先前和即将到来的车辆排放标准下已经改变和将要改变的非二氧化碳成分，从汽油车转向柴油车对气候缓解意味着什么？通过使用简单的气候模型，我们表明，在早期的排放标准（EURO 3 和 4）下，由于黑碳和氮氧化物（增强臭氧生成）排放量较高，柴油车在排放后十年内引起的变暖比类似的汽油车更大。然而，十年后，由于二氧化碳排放量较低，柴油车引起的变暖变得较弱。随着后期排放标准（EURO 5 和 6）的逐步实施，由于黑碳排放量较低，柴油车引起的短期变暖变得更小。因此，尽管结果受到限制假设和不确定性的影响，但二氧化碳税鼓励从汽油车向柴油车的转变并不与关注长期后果的气候缓解相矛盾。
