Kin Cheung / APCoronavirusWHO warns omicron poses 'very high' global risk as Covid variant spreads Omicron variant now in North America, Canadian officials sayWHO criticizes travel bans on southern African countries over new omicron variant
J. Scott Applewhite / AP fileCongressCongress faces jampacked end to 2021Billions and trillions: Climate efforts set for big boost if Build Back Better bill passesAs new debt limit showdown looms, lawmakers consider long-term solutions
Kirill Kukhmar / TASS via Getty ImagesClimate in CrisisBarren forests, dirty rivers, unbreathable air: Inside an Arctic city's vast pollution problemBig Oil's pollution in Canada is poisoning the environment — and may even be deadly
Shelby Tauber / The Texas TribuneU.S. news9 months after the Texas freeze, the power grid remains vulnerable
Bridget Bennett for NBC NewsU.S. newsHow clean is green? Nevada town fights to keep solar industry out of desert
Andrey Rudakov / Bloomberg via Getty ImagesWorldRussia says it's just business, but push to sell new fighter jet has U.S. in sight
