From the HuffPost/Canada: Climate Change Refugees: Coming Soon to a Country Near You. An excerpt:

The world will face a significant humanitarian challenge in coming years. The United Nations Refugee Agency says there are currently 45 million people forcibly displaced by conflict, persecution or natural disaster. According to the International Organization for Migration, the number of people who need new homes, food supplies and livelihoods will increase by at least half, due to climate change. And the international organization, which has studied the implications of environmental migration, says large increases in forced migration will lead to increased conflict, and greater environmental destruction, as migrants burden host communities and their resources.

This is the first time I have seen the term “forced migration.”