In the first study of its kind, scientists found a correlation between climate change and a rise in urban rat populations.

Based on individual trends within cities, Washington was by far the leader in rat increases, followed by San Francisco, Toronto, New York City and Amsterdam.

New Orleans went from almost 70 degrees to a record snowstorm within four days. In a few months, hurricane season will start, bringing a new trend of rapidly intensifying storms. Why it matters: The weather whiplash,

Anytime we get an Arctic air blast down this far south, this is an artifact of the polar vortex rearing its ugly head,” said climatologist Barry Keim .

Global warming is worsening droughts, making sea levels rise, and fueling deadly storms. Now scientists have a new problem to add to that list: Climate change is helping rat populations thrive in U.S.

A mass of air called the polar vortex has escaped the Arctic and plunged southward. Some scientists see the fingerprints of climate change.

Climate change is fueling a surge in rat populations across major US cities, with Washington, DC, seeing the worst increase over the past two decades, a new study said.The study published by Science Advances on Friday,