Editing High-speed rail (section)

====Pollution====
High-speed rail usually implements electric power and therefore its energy sources can be distant or renewable. The usage of electric power in high-speed rails can thereby result in a reduction of air pollutants as shown in a case study on China's high-speed railways throughout its development.<ref>{{Cite journal |last1=Yang |first1=Xuehui |last2=Lin |first2=Shanlang |last3=Li |first3=Yan |last4=He |first4=Minghua |date=2019-12-01 |title=Can high-speed rail reduce environmental pollution? Evidence from China |url=https://www.sciencedirect.com/science/article/pii/S0959652619330057 |journal=Journal of Cleaner Production |language=en |volume=239 |pages=118135 |doi=10.1016/j.jclepro.2019.118135 |bibcode=2019JCPro.23918135Y |s2cid=202318356 |issn=0959-6526}}</ref> This is an advantage over air travel, which currently uses fossil fuels and is a major source of pollution. Studies regarding busy airports such as LAX, have shown that over an area of about {{convert|60|km2|abbr=off}} downwind of the airport, where hundreds of thousands of people live or work, the particle number concentration was at least twice that of nearby urban areas, showing that airplane pollution far exceeded road pollution, even from heavy freeway traffic.<ref>{{cite web|url=http://cen.acs.org/articles/92/web/2014/05/Los-Angeles-Airport-Pollutes-City.html|title=Los Angeles Airport Pollutes City Air For Miles Downwind – Chemical & Engineering News|first=Deirdre|last=Lockwood}}</ref>