Early Earth atmosphere loaded with greenhouse gases, study finds

Impact

Greenhouse gases contribute to the glittering beauty of Venus in our night sky and are the source of many fears about global disaster, but 2.7 billion years ago, these same gases may well have helped to warm the early earth and contribute to early life, according to University of Washington researchers led by Sanjoy Som, who is currently a post-doctoral researcher at NASA's Ames Research Center.

If any group has more reason to complain about harsh news coverage than Republican candidates, it's probably scientists, especially those who are involved in atmospheric research, astrophysics, nanotechnology or bio-genetics. Headlines around the world covering the University of Washington study read "Study: Early Atmosphere Loaded With Greenhouse Gases." This is, of course, not the primary outcome of the research, which compared fossilized raindrop impressions found in 2.7 billion-year-old volcanic ash from South Africa to contemporary experiments conducted on recent volcanic ash from Hawaii and Iceland.

2.7 billion years ago, microbial life was present on Earth, but no plants and animals had yet appeared. The sun was about 30% cooler than it is today, and earth would be expected to be a frozen ice cube, but it wasn't. Liquid water was abundant. Prior to the research conducted by Dr. Som and his colleagues, scientists theorized that earth's atmospheric pressure was significantly higher during this period, leading to the warmer-than-expected climate. The University of Washington researchers compared the ancient raindrop impression to current impressions, discovering that ancient atmospheric pressure was similar to today's; thus, the warmer climate was likely to have been produced by a thick layer of protective greenhouse gases. According to Dr. Som, early Earth was very different from today's earth.

The University of Washington study shows that we are learning something new about the world we live in almost every day. A review of several articles on climate science shows that today's CO2 levels are higher than 2.1 million years ago, 15 million years ago, or 3 million years ago.

Or during the entire Carboniferous period ... 286-360 million years ago, the time when today's fossil fuels were created. Even basic climate change courses cover the carbon cycle, of which human activities are a part, and far from the whole. What can people learn from today's science report? Our planet is far more complex than any movie or article can cover and we still have a lot to learn.