 As an undergraduate I was majoring in physics, but of course also taking chemistry and biology and learning calculus and math. And I found, further I went along, that the more interdisciplinary what I was doing had to be. So physics was a good basis, but I need to know, to understand the atmosphere, I need to know atmospheric chemistry. Not just the nitrogen and oxygen, but the trace gases like CO2 and so on. And how does CO2 dissolve in the oceans? And how does that affect the biology of the oceans, the micro critters that live in the upper ocean? So partly I have to just learn those other fields myself and integrate them, and partly I have to work with people who are experts in say ocean biology or atmospheric chemistry and work together on teams to see how all those things play together.