Mary Hayden Hall: Seeing the evidence of global warming
To the editor:
I write of global warming, which I care a lot about.
Our understanding that people could impact the tiny concentrations of carbon dioxide in the atmosphere — and affect climate — began with the work of Svante Arrhenius around 1900. Over years of study, scientists have confirmed that global temperatures and levels of carbon in the atmosphere trend together over time. Concentrations of carbon in the air are now higher than they have been in hundreds of thousands of years.
It stands to reason that when, in a relatively brief period, humans released carbon into the air that had been sequestered for so long, there can be an impact. While there may be no imminent danger of dramatic change in ocean circulatory systems with rising water temperatures, it is a matter to keep in view, with the effects such change would have.
It’s pretty straightforward that open water reflects less radiation than snow and ice do, and that absorption of the sun’s warmth into newly opened waters contributes to rising temperatures. It’s also easy to understand that methane deposits that are now frozen will augment temperature changes as they thaw and release gas.
Arctic temperatures are way up. We are aware that corporations and countries want to exploit resources and waterways newly accessible there. The movie “Chasing Ice” documents a man’s heroic efforts to show the dramatic melting of most glaciers around the world. We have just read of puffins starving due to sea water warming in Maine.
Understanding is accessible to any one who can bear to look at what is going on.
Mary Hayden Hall