[music] How does climate change affect humans? There are four really important ways that climate change affects humans. Number 1: as the planet warms up, we're going to redistribute rainfall, which is going to affect our water resources and parts of North America May get a lot drier. Number 2: as the polar ice melts, sea levels are going to rise and a lot of people and a lot of the world's major cities are right on coasts and that's going to impact them. Number 3: things like the species distributions, where we can grow food, they are going to change as the planet warms up. So the range over which you can grow corn and things will change. 4: the oceans are going to get more acidic as more CO2 dissolves in them. There are untold ramifications from that. There are the possibilities of radically altering the food web in the ocean, which can affect everything from the composition of the atmosphere to the ability of the oceans to provide food for us. [music]