Background: The climate of Maine is extremely variable. If you live in the inland north woods on the border of Canada, like in St. Francis township, the average high temperature in January is 24° F, and it doesn’t get above freezing until March. The average high in January in Portland, a coastal city in the far southern part of the state, is 33° F, and by March the average high is 44°F. What factors do you think might influence the temperatures and how do those different temperatures affect the state?

One phenomenon that is affected by temperature is “lake ice out”. Lake ice out is defined different ways, but a common definition is that it’s the day when enough ice has melted that you can navigate a boat from one end of the lake to the other (). In the graph the average lake ice out dates, in days since January 1, for lakes in Maine, New Hampshire and New Brunswick, are graphed against distance from the coast. (Note: The Y-axis is in Julian Days.  Julian day refers to the number of days since Jan 1 in that year)

Data Source: Timothy, P. R., & Swindles, G. T. (2014). Influence of ocean–atmospheric oscillations on lake ice phenology in eastern North America. Climate Dynamics. doi:10.1007/s00382-014-2415-y