Climate Change: Past, Present, and Future?


Are gassy cows really causing climate change? More than 440,000 hits result from the internet search, "Do cows cause global warming?" It's clear that many are eager to know if these farm animals really are responsible for the change in climate conditions we see around us. When cows eat plants, they rely on bacteria in their stomachs to digest their food. While this is happening, methane, a greenhouse gas 25 times more powerful than carbon dioxide, is released into the atmosphere contributing to the earth's warming, but are these brazen gas-venting cows really the problem here? We can't solve this puzzle without first understanding what the greenhouse effect is and the role that carbon, a chemical element contained in all known living things, plays in keeping our planet warm.

Greenhouse gases, such as water vapor, nitrous oxide, and carbon dioxide, act much like the glass walls in a greenhouse. They allow energy from the sun to be absorbed by the earth and its atmosphere while slowing down the resultant heats lost into outer space. The enhanced greenhouse effect is very similar to increase in the number of blankets on your bed. The more blankets you pile on, the hotter your bed becomes. If you don't remove any of these blankets, your bed will become warmer and warmer. Anthropogenic or human-caused climate change occurs when the average global temperature increases due to the enhanced greenhouse effect. What role does carbon play in keeping our planet warm? Carbon can exist in 3 states, solid, liquid, and gas.

However, of the 3 states of matter, it's only in its gas form that carbon contributes to global warming, so anything that converts a solid or liquid form of carbon into a gas will contribute to the enhanced greenhouse effect. Carbon gases aren't necessarily a bad thing though. As a matter of fact, carbon gases are a vital component to life on earth. Ecosystems need these gases to function, and the process of converting carbon into its different states is actually a very normal process in nature. When plants and animals die, bacterial decomposition extracts the energy from the carbon bonds in their tissues, releasing all of the carbon in their bodies into the atmosphere in the form of carbon gases, such as carbon dioxide or methane. New generations of photosynthesizers then incorporate that carbon into their bodies using energy from the sun. Animals then eat those photosynthesizers, also adding carbon to their bodies.

The cycles continues converting carbon gases into solid tissues via photosynthesis and converting those solids back into carbon gases via decomposition and respiration. In this cycle, the total amount of carbon that is cycling between living things in the atmosphere remains the same. All right, so if the earth's carbon levels naturally balance themselves, what is causing the buildup of carbon gases that is raising the earth's temperature? Let's look back to about 300 million years ago. During the early carboniferous period, there was an extraordinary abundance of life due to an alignment of biological and climatic factors. The evolution of eggs that resisted drying out allowed for the radiation of animals from the sea onto land. Ecosystems became highly productive, and with climate conditions much warmer, moister, and less seasonal than today, there was an abundance of life. When these abundant organisms died, their remains accumulated more quickly than they could decay.

With higher sea levels at the time, the land often flooded, which also reduced the rate of decay. With each growing cycle and layers of dead organisms continuing to build up, more carbon was removed from the atmospheres and buried in the bodies of dead organisms, which eventually contributed to global cooling at the end of the carboniferous period. Over millions of years, the buried material was transformed into fossil fuels, which are essentially prehistoric solar energy that was captured by photosynthesis in plant and algae cells. What happens when we burn these fossil fuels? We access that stored energy and release carbon gases that were removed from the carbon cycle 300 million years ago, thereby contributing to today's global warming. In other words, unless our cows are producing their gassy emissions by eating fossil fuels, they're not increasing the total amount of carbon that is cycling between the atmosphere and lifeforms and are therefore not the problem here.

We are, because we continue to develop and use technologies that extract energy from fossil fuels releasing carbon gases. Fortunately for us, we have identified the issue and can now focus our resources on finding solutions. To do this, we need to either discontinue burning fossils fuels or develop technology that mimics photosynthesis, which will convert our human-caused or anthropogenic carbon gases back into liquids and solids that can be buried for long-term storage..