Wait a minute, that’s not a rock. Photo by Ralph Jewell

Palmisano Park, Chicago. Original quarry high wall in background.

Earth’s climate has gradually cooled for the last 50 million years, culminating in Northern Hemisphere ice ages where ice sheets periodically advance and retreat. The ice last began to rapidly retreat about 18,000 years ago. Based on current greenhouse gas emissions, global temperatures over the next century and beyond will reach levels not reached for millions of years. CREDIT Thomas Westerhold. Ref: Westerhold, T., et al. 2020. An astronomically dated record of Earth’s climate and its predictability over the last 66 million years. Science 369(6509):1383–1387.

Spectators at the Gondwana vs. Laurentia soccer game at the 2012 quadrennial international ICHNIA meeting in Newfoundland. Such events help build relationships among researchers from diverse backgrounds.

Roy Plotnick

Paleontologist, geologist, ecologist, educator. Professor at the University of Illinois at Chicago. Website:https://sites.google.com/uic.edu/plotnick/

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