Henry David Thoreau’s river journals from the 19th century are now helping scientists understanding the effects of climate change on New England's seasons. Thoreau's meticulous notes on river ice, floods, and seasonal changes reveal how warmer climates have altered natural cycles over the past 170 years. Modern research shows that Thoreau's "Break-up" and "Winter White" seasons may disappear entirely as climate change continues to reshape the environment. “The great overlap of beginning and ending dates for discrete river seasons [has made] phenological interpretations of climate change complex,” he said. “In spite of this challenge, Thoreau’s river phenology provides an unparalleled opportunity to render the abstractions of climate change into tangible realities.”