Climate change could threaten food supply chains from fields to consumers’ forks, and trigger further food price spikes such as the one the world is currently experiencing following the drought in the United States. According to food security experts contributing to a United Nations report on global warming (due to be published in 2014), governments should pay more attention to the impact of extreme weather events, such as heat, drought and floods, on food supplies. "It has not been properly recognised yet that we are dealing with a food system here. There is a whole chain that is also going to be affected by climate change", said Professor Dr John Porter of the University of Copenhagen. He added that he was only stating his personal opinion, not that of the UN panel. Floods could destroy roads or bridges, and prevent food from reaching processing factories or supermarkets. Heavy storms could destroy grain storage facilities. The experts said that extreme weather events require more research into drought- and flood-resistant crops.