Worldwide food shortages are expected to become more common because of global warming. Global warming is a way that humans have modified the planet. Part of the theme of nature culture is looking at how humans modify the Earth. Shortages can also be caused by the globalization of food production. Not all countries have developed systems for food production. Countries, like those in the Middle East, that rely on other countries to import food are the ones that are expected to be impacted the most.