As you study economics, you realize incentives are everywhere. Unfortunately, the incentives aren't always positive. For those who receive funding to study climate change - the incentives are skewed to encourage findings that say there is climate change. If it is suddenly discovered that climate change will not be damaging, that would destroy the careers of thousands of researchers.
Because of these bad incentives, any rational person should harbor at least some doubts about the possible impact or likelihood of climate change. As an economist, I find this especially true since projections of climate change are often based on theoretical models. Those in economics, more than in almost any field, should understand that just because there is consensus on an issue, doesn't mean the model is correct. (Mortgage crisis, anyone?)