This blog is run by the Center for American Progress, which is a Democratic-oriented group. But, the site seems to have good information about climate change science, along with messaging and the political dynamics.
Be sure to visit Green Party oriented sites for a different perspective on things:
Liberty Tree - works to promote citizen engagement and grassroots democracy outside the two-party system.
Green Change - an excellent social networking, blogging, news aggregation site, and coordination zone for Green Party activism.
Good politics grow with good ideas!