Without much fanfare from the American press, the world approached a significant threshold. According to the Mauna Loa Observatory Scripps CO2 program, daily averages of carbon dioxide (CO2) temporarily reached 400 parts per million. Climate scientists noted that the last time there was so much CO2 in the atmosphere was about 2.6 – 5.3 million years ago, or the Pilocene Epoch. To give you a handle on what was going on, it’s thought that the first Australopithecus evolved during this era — an ancient ancestor to today’s human.
CO2 is a greenhouse gas — produced by burning coal and petroleum products, and exhaled by humans and land animals. In the environment, too much CO2 traps heat close to earth’s surface, creating a greenhouse effect. Climate scientists have noted that for decades, there has been an alarming rise in CO2 in the atmosphere, with human activity contributing to the problem since the Industrial Revolution.
A warmer planet doesn’t sound like a bad idea when your furnace is working overtime in early May and you’re still wondering if it is safe to put away the winter coat. However, a warming climate brings with it many problems, including widespread droughts that affect crop production, the warming of oceans that lead to bigger and more destructive weather systems, the destruction of fragile ecosystems like coral reefs, more frequent heat waves that impact human health and safety — to name just a few.
Climatologists have been concerned for decades that we’re doing ourselves irreparable harm by ignoring, or actively denying, that these changes are taking place and that human activity is responsible for part of the changes. The issue has become a political football, with one team trying to play offense and getting government and individuals to make changes that will slow the change, and the other team defending the status quo. In the meantime, CO2 continues to accumulate in the atmosphere — moving quietly toward another threshold, another point of no return.
For more information about CO2 levels, I’d encourage you to visit the Web site http://co2now.org/ for monthly averages from monitoring sites, insightful (non-alarmist) articles on effects of climate change, and much more.