The Adventures of Alexander von Humboldt
A young scientist leaves his homeland and embarks on a long, dangerous, but extraordinary journey. Along the way, he recognizes the harmful consequences of man-made climate change and tries to draw public attention to them.
Von Humboldt was basically the first "ecologist" and already brought these ideas to politicians at that time. Even then, von Humboldt was aware of the harmful consequences of deforestation and artificial irrigation, thus anticipating the urgent issues of our time.