The United States and other countries hiked their targets for slashing greenhouse gas emissions at a global climate summit hosted by President Joe Biden, an event meant to resurrect U.S. leadership in the fight against global warming. Tax breaks for fossil fuels ‘a disgrace,’ Greta Thunberg tells U.S. Congress U.S. to double public climate finance to developing countries by 2024 U.S. seeks to conserve more farmland as crop prices climb U.S. moves to withdraw Trump rule barring California vehicle emissions regulations