J Farmer's Almanac

Paleoclimate science from Jesse Farmer

Earth’s climate is warming at its fastest rate in millions of years. Future generations face climate analogs with unfamiliar names like Eocene, Miocene, and Pliocene.

To avert a climate catastrophe, we urgently need to know more about where we’re headed and how we can avoid the worst impacts.

These problems motivated the launch of J Farmer’s Almanac back in 2015. What started as a blog on climate science topics has evolved into the home for an entire lab group researching how and why climate changes.

The PaleoLab at UMass Boston’s School for the Environment investigates how Earth’s carbon and nitrogen cycles responded to past climate change. We use this information to understand and predict our climate future.

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Latest Updates

10/3/2025: New publication in Science!

Our N isotope paper on the surprisingly stable 5-million year history of nutrient upwelling in the eastern Equatorial Pacific (co-led by Patrick Rafter) was just published. Check out the Perspective by Rosenthal & Hess and the UMB Press Release!

9/7/2025: PaleoLab @ 15th International Conference in Paleoceanography (ICP15) in Bangalore, India!

Fantastic week of data sharing & progress on the Arctic, Benguela Upwelling, and Southern Ocean projects – & congrats to Shalan for receiving honorable mention in the Biogeochemistry & Climate section’s best poster award!!

4/21/2025: New publication on the Central American Seaway in Paleoceanography & Paleoclimatology!

Open access paper available from the link above. Quoting the Plain Language Summary:

The Central American Seaway was the last tropical connection between the Atlantic and Pacific Oceans in Earth’s history. Despite numerous studies, the timing and sequence of events leading to the closure of the seaway remain debated. Here we present new chemical data measured in marine sediments that speak to the transport of seawater and associated nutrients across the seaway. Our results focus on a time when existing data indicate a critical shoaling of the seaway. By comparing our chemical results with a computer simulation of ocean transport, we find four phases of progressive shallowing of the seaway between 4.6 and 4.1 million years ago. Our chemical data indicate limited exchange between the Pacific and Atlantic Oceans after 4.1 million years ago. We interpret this to indicate that the seaway was effectively closed at an oceanic scale after 4.1 million years ago, although our results do not rule out the existence of small, shallow passageways in the Panama Isthmus into the late Pliocene.