Since World War II, the Peace Prize has principally been awarded to honour efforts in four main areas: arms control and disarmament, peace negotiation, democracy and human rights, and work aimed at creating a better organized and more peaceful world. In the 21st century the Nobel Committee has embraced efforts to limit the harm done by man-made climate change and threats to the environment as relevant to the Peace Prize.
https://www.nobelpeaceprize.org/nobel-peace-prize/about-the-nobel-peace-prize/