Biogeochemistry and climate change

SALISBURY— The long-term effects of carbon dioxide on the planet’s past and future were explored and explained during a Zoom talk sponsored by the Scoville Memorial Library and the Salisbury Association on Saturday, Jan. 23.

More than 80 viewers tuned in to hear William H. Schlesinger, president emeritus of the Cary Institute of Ecosystem Studies in Millbrook, speak on the significant effects of carbon dioxide on the Tri-state region and the world at large. 

The title of the talk was “From New England to Global Climate Change: Impacts and Responses.” 

“It all revolves around carbon dioxide,” Schlesinger began, discussing regional impacts of documented climate change in the eastern U.S.  One of his accomplishments was to have been among the first to measure the amount of carbon retained in soil’s organic matter around the world. The ability to quantify led to an ability to predict the effect of those soil conditions and attendant human interference on climate worldwide.

Dramatic change, worthy of attention

Scientists have measured the amount of carbon dioxide trapped in air bubbles within the Arctic ice pack. The Industrial revolution brought a significant uptick.

“We’ve had a benign history,” Schlesinger noted. “For the period we have a record of, the climate has been relatively stable.”

Over the past 20 years, however, the Earth has seen a significant rise in temperatures. Northern latitudes have gotten warmer, he reported. The Northeast is seeing change projected at 1 degree Celsius, which translates to about 2 degrees Fahrenheit. In the northeastern states, a future climate would align with present-day Virginia, with warmer temperatures and less snowfall.

More melting of the Greenland icepack would bring rising oceans and higher tides. Globally, higher tides are measuring about 3.2 millimeters each year recently.

Three affected elements being researched to define the real effects of climate change are: health of forests, crops and people.

In the northern U.S., Schlesinger noted, forest tree populations include, notably, beech and maple, the health of both driven by temperature.  Where they do not thrive, they leave. The pine forests of the south would migrate westward.

“The fact that the changes are so dramatic is worthy of attention,” he said. 

The end of local maple syrup

Study of maple sap flow in liters per tap is instructive. Presently the flow per tap can be expected to range between 80 to 100 liters, but later in the century the maple syrup industry will have disappeared, having moved farther north to Canada.

“It’s not that there won’t be forests; it’s that the nature of the forests will change,” Schlesinger said.

Crops and the food supply will also change. Pests that are prevalent in the south now will follow the crops northward, taking advantage of the warmer conditions. 

For example, the southern corn earworm will become more prevalent in the northern states. The same would apply to most other crop pests, he predicted, negatively affecting farmers and, for the rest of us, bringing higher food prices.

Concerns for human health include tick-borne diseases, as ticks will over-winter successfully and thrive. Malaria also takes hold in warmer, wet climates.

Heightened levels of carbon dioxide interact with the ocean waters, making them more acidic, lowering the pH alkaline levels. With that change, sea life, including mussels, oysters and the like, become unable to build their shells, for which they need carbonate materials.

A North Carolina study, in which Schlesinger participated, indicated that trees grow faster, gaining girth, when carbon dioxide increases, but so do invasive vines observed to be marching northward.  

Because vines are laden with leaves, they grow and spread faster these days. Poison ivy and invasive bittersweet were cited as examples by Schlesinger, familiar to most area residents.

One promising antidote to rising carbon dioxide, according to Schlesinger, is the promise of solar energy as a power source for homes. He spoke of the cost benefits to the homeowner over time.

Schlesinger is presently serving as a trustee for the Natural Resources Defense Council (NRDC) in New York. His blog is at https://blogs.nicholas.duke.edu/citizenscientist.