January 19, 2017 — Hundreds of articles have been written about the largest volcanic eruption in recorded history, at Indonesia’s Mt. Tambora just over 200 years ago. But for a small group of New England-based researchers, one more Tambora story needed to be told, one related to its catastrophic effects in the Gulf of Maine that may carry lessons for intertwined human-natural systems facing climate change around the world today.

In the latest issue of Science Advances, first author and research fellow Karen Alexander at the University of Massachusetts Amherst and 11 others including aquatic ecologists, climate scientists and environmental historians recount their many-layered, multidisciplinary investigation into the effects of Tambora on coastal fish and commercial fisheries.

Alexander says, “We approached our study as a forensic examination. We knew that Tambora’s extreme cold had afflicted New England, Europe, China and other places for as long as 17 months. But no one we knew of had investigated coastal ecosystems and fisheries. So, we looked for evidence close to home.”

In work that integrates the social and natural sciences, they used historical fish export data, weather readings, dam construction and town growth chronologies and other sources to discover Tambora’s effects on the Gulf of Maine’s complex human and natural system.

The 1815 eruption caused a long-lasting, extreme climate event in 1816 known as the “year without a summer.” As volcanic winter settled on much of the Northern Hemisphere, crops failed, livestock died and famine swept over many lands. In New England, crop yields may have fallen by 90 percent. The researchers found that 1816 was also called “the mackerel year,” a clue to what they would find regarding fisheries.

Besides Tambora’s climate effects, the authors examined other system-wide influences to explain observed trends. These included historical events such as the War of 1812, human population growth, fish habitat obstruction due to dam building and changes in fishing gear that might have affected fisheries at the time. Employing historical methods in a Complex Adaptive Systems approach allowed them to group and order data at different scales of organization and to identify statistically significant processes that corresponded to known outcomes, Alexander says.

Read the full story at Phys.org