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Secrets of the Past Unlocked by Fossil Pollen

Detailed Description

Did you know fossil pollen and spores can help us understand past climate variability?

You are looking at microscopic images of ~55-million-year old pollen grains and spores that were isolated from a geologic unit known as the Marlboro Clay in Maryland. The presence of plant groups now found in tropical, subtropical, and temperate areas indicate that climates were warmer and wetter in the mid-Atlantic region during a global warming event known as the Paleocene-Eocene Thermal Maximum (PETM).

The PETM was a geologically short-lived event (~150,000 years) when carbon dioxide levels increased rapidly, oceans became more acidic, temperatures rose, and precipitation patterns changed. This research is part of a coordinated effort to document and understand how the distribution of plants and animals was affected by such a large-scale climate event. By using the results of past natural experiments such as the PETM, geologists are helping improve model capabilities to accurately forecast impacts of future change that could affect agriculture, forestry, and other sectors of our economy.

You can learn more about the work USGS scientists are doing with fossil pollen at the Florence Bascom Geoscience Center Pollen Laboratory website.


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