By Nate Hoffert, Staff Writer
On Thursday, the University of Pennsylvania’s Distinguished Professor of Earth and Environmental Sciences Joe Francisco visited Gettysburg College to present his lecture, “So Much Water in the Atmosphere.”
Speaking to a crowd of students across all majors in the Bowen Auditorium, Francisco opened his lecture with a humorous story about the climatology of the United States. Specifically, he, as a Texas native, forgot to bring a coat when visiting New England for the first time in his life.
He chuckled and said, “An MIT staff member even asked how I was admitted!”
Francisco began the scientific portion of his lecture with a clarification about the differences between climate and weather. Essentially, climate encompasses the long-term patterns or trends of meteorological conditions, whereas weather involves more short-term weather events.
He stated, “The difference is in the timescale. Weather is what you see when you walk outside the door. Climate is about consistency.”
He stressed the importance of understanding this difference when studying climate change.
“Climate change is the alteration in the long-term patterns and statistical averages of meteorological events—of course, there are oscillations, but just because it feels slightly warmer or colder on random Tuesday…that’s not the evidence used for climate change,” he said.
“Climate is determined by radiative forces—factors that alter the balance of incoming solar radiation relative to the amount of heat that escapes,” said Francisco. “Essentially, radiative forces are energy—typically sunlight. Some of these other forces, including the greenhouse effect and the Albedo effect, along with others—some which cool the atmosphere, and some which heat up the atmosphere. The concern for global warming is due to the enhanced greenhouse effect.”
He added onto his statements, saying, “Carbon is usually naturally balanced through the carbon cycle, but because of major human interference, a significant amount of carbon is now in the atmosphere and oceans…we, as scientists, would like to alert people about the fact that certain carbons have a lifetime of 75-2,000 years, and that knowledge combined with the knowledge about the positive feedback loops with global warming…people need to know that we’re in a situation that may last a good amount of years even after we stop putting carbon into the atmosphere.”
He noted, “One of the positive feedback loops with climate change is with the chlorine in the atmosphere [chlorine destroys the ozone layer]…the sun sends energy (heat) into the ocean, and then this heat rises into the atmosphere, and with that, the carbon in the ocean, too, and then the chlorine in the atmosphere gets reactivated, eating away at the ozone layer…which in turn, increases the amount of energy from the sun that the Earth’s oceans are exposed too, which worsens the cycle.”
He also noted the role of dihydrogen monoxide—water—and its role in the various chemical reactions of the atmosphere; his team of students was one of the first groups to understand the role of water. Prior to his research, it was relatively ignored.
Francisco ended his lecture on a positive note by encouraging students to appreciate the occasional cloud day. “Clouds use water to catalyze chemistry…clouds act as mini-reactors that clean up the atmosphere very well, which is why the air always smells nice after a cloudy day!”
The lecture ended with a few closing remarks, and he hoped that students now had “A better understanding of the chemistry in our atmosphere.”
