As part of President Barack Obama’s trip last week to Cuba and Argentina, the U.S. announced that it will work separately with the two nations to confront climate change. During the first U.S. presidential trip to Cuba in decades, the governments of the two nations agreed to cooperate on addressing ocean acidification. They also are exchanging information on helping farmers cope with the increases in drought, heat stress, and intense precipitation as well as the changes in pests that are predicted to accompany anthropogenic climate change. Argentina and the U.S., meanwhile, agreed to work together through a treaty called the Montreal protocol to phase down the global production and use of hydrofluorocarbons, widely used refrigerants that are potent greenhouse gases. The two nations said they will also collaborate through the International Civil Aviation Organization to reduce greenhouse gas emissions from international commercial air flights. Argentina and the U.S. also pledged to cooperate on nuclear power R&D and safety.