A U.N. expert is warning that more extreme weather, higher temperatures, floods, droughts and rising sea levels linked to climate change are threatening people's access to food over the long term.

Hilal Elver, the U.N. special rapporteur on "the right to food," predicts the negative impact from climate change on agriculture could subject another 600 million people to malnutrition by 2080.

In a statement on Tuesday before a U.N. climate conference in Paris starting Nov. 30, she recommended a shift from large-scale, industrial agriculture to "agro-ecology" that supports the local food movement, small-scale farmers and the environment.

Most climate scientists say the climate is changing largely because of the buildup of heat-trapping gases from the burning of coal, oil and gas. Some public officials and a few climate scientists disagree.