Jenny Smith
Jefferson City
Dear Editor:
Earth’s last ice age spanned from 2.6 million to 12,000 years ago. There were seven cycles of warming and cooling in that ice age with CO2 fluctuations ranging from 120-290 ppm corresponding directly to temperature fluctuations from 41.5 to 51.5 degrees Fahrenheit. Before the end of that last ice age many animal species became extinct and humans struggled to survive. It took 5,000 years to emerge from that ice age as temperatures and CO2 levels rose and stabilized about 7,000 years ago. After that, earth’s global temperature and CO2 varied only slightly around 56.5 degrees and 290 ppm of CO2. With these higher temperatures and CO2 levels, there was less ice and more rainfall. The earth became greener and humans flourished.
Beginning with the industrial age of the last half of the 1800s, there has been a dramatic and unprecedented rise in global CO2 levels and corresponding temperatures. Earth’s average global temperature last year was 58.3 degrees, with CO2 at 405 ppm; a change of 1.8 degrees and 115 ppm since 1870. The last time our earth experienced this much climate change it took 1,000 years.
The relationship between rising temperature and CO2 is well known. As the sun’s radiation penetrates the atmosphere the earth heats up. What is not absorbed is reflected back, but CO2 and other greenhouse gases trap heat. As CO2 levels rise, more heat is retained and global temperatures rise. This causes more water to evaporate, thus more precipitation. Water vapor also traps heat. When warm and cold air collide, the result is high winds and violent storms.
CO2 is a byproduct of the burning of fossil fuels and has accelerated greatly in the last century. Consider that 207 billion pounds of carbon are burned and spewed into the atmosphere every day, something our earth did not have to contend with in past millennias. Our population has exploded from 1.6 billion in 1900 to 7.7 billion today, causing further strain on the earth’s resources.
The earth’s atmosphere is a thin barrier (like the outer layer of an onion) holding nitrogen, oxygen, argon and CO2 in a delicate balance. Slight changes in this balance causes havoc, just like a slight rise in our body temperature means we are sick. Our planet is sick. We all need to be part of finding a cure.