The US tightens greenhouse gas emission standards for heavy-duty vehicles
/ The US has new standards for planet-heating tailpipe pollution from vehicles like 18-wheelers and buses. p>span:first-child]:text-gray-13 [&_.duet–article-byline-and]:text-gray-13″> By Justine Calma, a senior science reporter covering climate change, clean energy, and environmental justice with more than a decade of experience.…