It will surprise no one that the Hollywood Hills in Los Angeles and New York’s Upper East Side rank among the nation’s hottest neighborhoods on Zillow. But who knew that the list of most-searched neighborhoods also includes an enclave called Elkhorn, in Omaha, Nebraska? Or Northwest El Paso, the Texas border town? Or Encino, in…
Based on PM2.5 levels, an air pollutant with small particles that are literally everywhere, here's how cities around the world have gotten better and worse when it comes to air quality since 2019.