Studies of past weather and climate events can be useful in terms of helping us to figure out current and future climate, because they give us a way to test climate models and assumptions about climate behavior. This story from Yale Climate Connections describes a volcanic eruption that occurred in Alaska in 43 BCE that caused significant cooling for almost a decade and how it is being used to look at models of past climate with an eye to improving models in the future.

Source: Bionet via Commons Wikimedia.