Witness Tree: Seasons of Change with a Century-Old Oak

An intimate look at one majestic hundred-year-old oak tree through four seasons--and the reality of global climate change it reveals.

In the life of this one grand oak, we can see for ourselves the results of one hundred years of rapid environmental change. It's leafing out earlier, and dropping its leaves later as the climate warms. Even the inner workings of individual leaves have changed to accommodate more CO2 in our atmosphere.

Climate science can seem dense, remote, and abstract. B...