NASA is a business and will do what it has to to secure its position

Even if that means abandoning space exploration and hitching up the to global warming bandwagon. The closure of the shuttle program meant an inevitable loss of myriad jobs and money. Since they twiddled their thumbs and didn't work at it a new vehicle is at least a decade away, they needed desperately to shore up "the company" so they looked around for a new avenue from which to justify their existence. What field was being flooded with money that they could go into? Global warming. "Earth observation" to facilitate a place for themselves in that lucrative field.