US seeks to polish tarnished reputation with new climate change pledges

The United States hopes to restore its shattered credibility when it hosts a climate change summit next week by pledging to cut its greenhouse emissions by at least half and securing agreements from allies for faster reductions, according to two sources familiar with the matter.

A 50 percent reduction from 2005 levels by 2030 is a minimum level urged by environmental groups, hundreds of corporations and European Union lawmakers. It would be the first upgrade of the US climate target since 2015, when former president Barack Obama pledged a 26-28 percent reduction by 2025...