What does a commercial fruit tree grower in Warren County have to fear from global climate change?
A lot, according to a Vanderbilt University scientist and engineering professor. The fear deepens if that nurseryman hopes to leave his farm to his children and grandchildren.
Dr. Jonathan Gilligan told the Rotary Club of McMinnville last Thursday how most of the peach crop in Georgia was ruined by a late freeze in March 2017. The economic loss to the state’s total agricultural output was estimated at $1 billion, but this kind of devastation “could become a regular occurrence if nothing is done to combat the problem,” the Chattanooga Times Free Press reported in its Dec. 5 edition.
The problem, as underscored repeatedly and dramatically in the 2018 National Climate Assessment released last month, is climate change. In the case of the iconic Georgia peaches, the villain was a warmer late-winter that encouraged premature flowering of fruit trees, followed by a late-season freeze that damaged the tender buds and led to a poor-quality product.
Major shifts in Earth’s climate were first documented by French mathematician Joseph Fourier in the 1820s, Gilligan said, explaining recognition of these effects is nothing new. Subsequent generations of scientists pressed climate studies further, examining the cycles of Ice Ages and the thermodynamics of the planet and its enveloping atmosphere.
But researchers had to wait until digital computers became available in the mid-20th century before they could pinpoint carbon dioxide, methane and water vapor as heating-trapping molecules whose accumulation surged in the Industrial Revolution powered by coal-fired energy.
“A wait-and-see policy may be waiting until it’s too late,” the Rotary speaker said.
“Global warming could be irreversible,” Gilligan said in an apparent reference to what is commonly described as the “tipping point” when, theoretically, Earth’s temperature could soar in a short period, likely causing swift extinction of much of the plant and animal life, including the human species.
The climate change discussion has been clouded by political influences, despite the proven facts warning of the existential threat of rising temperatures. Climate-change sceptics are often identified with conservation politics, Gilligan noted, but it was the late President George H.W. Bush who signed the United Nations Framework on Climate Change.
While President Trump says he is unconvinced by the overwhelming consensus in the scientific community, his Department of Defense is spending intellectual energy and taxpayer dollars in strengthening its position against such major threats as sea-level rise, polar ice melting, hurricane damage and foreign insurgencies sparked by food and fuel shortages.
“Climate change is a threat multiplier,” said Gilligan.
The Vanderbilt professor shares more of his insights this week on 91.3 WCPI’s “Focus” interview program. The half-hour conversation with Gilligan airs Wednesday at 5:05 a.m.; Thursday at 1 p.m.; and Friday at 1:05 a.m.