Washington's Crossing Presaged Climate Change

Crossing of the Delaware River in 1776 highlighted the role of weather in military strategy, foreshadowing the impact of climate change.

Published on Feb. 15, 2026

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On Christmas 1776, General George Washington's surprise crossing of the near-frozen Delaware River was a pivotal moment in the American Revolution. The cold weather that enabled Washington's victory also presaged the impact of climate change, as average winter temperatures in the Philadelphia area have risen 5.5 degrees since 1970. Experts say that while cold and snow will continue, there will be less of it as the climate continues to warm due to human-caused carbon emissions dating back to the Industrial Revolution around the time of the American Revolution.

Why it matters

Washington's crossing of the Delaware highlighted how weather and climate can play a decisive role in military strategy and the course of history. As the climate continues to change, understanding this historical precedent can provide important context for how global warming may impact the world going forward.

The details

In 1776, the cold weather and ice on the Delaware River were key factors that allowed Washington to surprise the British forces at Trenton. Experts say that had the weather been more mild, the Americans would have likely encountered stronger resistance. However, the steady increase in average winter temperatures in the Philadelphia area since then, driven by rising carbon emissions since the Industrial Revolution, shows how the climate has already begun to shift.

  • On Christmas 1776, Washington led the Continental Army in a surprise crossing of the near-frozen Delaware River.
  • Since 1970, average winter temperatures in the Philadelphia area have increased by 5.5 degrees.

The players

George Washington

The commanding general of the Continental Army who led the surprise crossing of the Delaware River in 1776, a pivotal moment in the American Revolution.

Alex Robb

An educator at Washington Crossing Historic Park who discusses how the cold weather and ice on the Delaware River enabled Washington's victory.

Jen Brady

A data analyst at the science non-profit Climate Central who has researched the steady increase in average winter temperatures in the Philadelphia area since Washington's time.

Eric Steig

A glaciologist at the University of Washington in Seattle who studies ice cores that contain air bubbles from the 18th century, providing a "time machine" into the past climate.

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What they’re saying

“It does a lot to impede the crossing and endanger the whole operation, but it actually becomes our shield.”

— Alex Robb, Educator, Washington Crossing Historic Park (cbsnews.com)

“Looking back, had the weather proven more mild, they most definitely would've encountered resistance outside Trenton.”

— Alex Robb, Educator, Washington Crossing Historic Park (cbsnews.com)

“Ever since Washington was here, there has been a steady increase.”

— Jen Brady, Data Analyst, Climate Central (cbsnews.com)

“It's this sort of magical way of going back in time. It's a time machine.”

— Eric Steig, Glaciologist, University of Washington (cbsnews.com)

“We began burning fossil fuels, and we're doing it really fast.”

— Eric Steig, Glaciologist, University of Washington (cbsnews.com)

What’s next

Experts say that as the climate continues to change, understanding the historical precedent of how weather and climate have impacted military strategy and the course of history can provide important context for how global warming may impact the world going forward.

The takeaway

Washington's crossing of the Delaware River in 1776 not only marked a pivotal moment in the American Revolution, but also presaged the impact of climate change. The cold weather that enabled his victory has since given way to steadily warming winters, a trend driven by rising carbon emissions since the Industrial Revolution. This historical example highlights how the changing climate can reshape the world in profound ways.