In order to truly combat the climate crisis we are facing, we must first understand the processes behind it. Climate change, specifically global warming, is driven mostly by the greenhouse effect. The planet receives its light and a significant part of its heat from the sun. Although a big portion of that heat and light are reflected back into space, certain molecules hinder this, trapping the heat which is raising the global temperature of our planet. The biggest greenhouse gas isn’t actually carbon dioxide or methane, but water vapor.

Water vapor in our atmosphere is actually responsible for the greatest influence of the greenhouse effect on our planet. Without water vapor, our planet would be so cold that water wouldn’t be found naturally in liquid form. By itself, the greenhouse effect is one of the amazing phenomena that help sustain life on our planet, but of course anything in excess becomes a problem. Since water vapor levels are constant in our atmosphere we can rule them out as a culprit for climate change. From here we turn to carbon dioxide and methane, the other two significant molecules that impact climate change.

Carbon dioxide is the molecule that has been studied the most with regard to climate change. Carbon dioxide levels have been accurately estimated throughput the past .75 billion years of Earth’s history. By 1950, we reached a level of carbon dioxide that hasn’t been recorded in almost a million years. At the moment, we are at over 400 ppm CO2 levels, almost double what it was a century ago. Although CO2 levels have reached above this in the geologic past, the planet experienced severe climate change: there was no ice caps, no coral reefs, extreme storms were very common, pretty much all the problems we are facing now.

So where does the atmospheric CO2 come from? As we respire we produce CO2 naturally, but this is easily removed by plant photosynthesis, although we are losing plants at an alarming rate. Carbonate rocks, most prominently limestone, are composed of carbonate CO-23 which will break down into CO2. Although this isn’t the driving factor of climate change now, it has been in the geologic past and is affecting coral reefs across the globe. As sea levels rise and coastal erosion becomes a more severe problem, carbonate rocks will break down faster, creating a positive feedback loop for CO2 increase. As more coral reefs become destroyed, they will also become a source for carbon dioxide, since they are composed of carbonate.

Although all of these mechanisms of inputting CO2 into the atmosphere are extremely important and need to be studied, they are all secondary problems compared to the input of CO2 from the burning of fossil fuels. Fossil fuels are fuel sources, primarily oil (petroleum), natural gas, and coal, that are made from plant matter and microorganisms, such as plankton, that lived millions of years ago that have been deep in the Earth’s crust under extreme pressures. They are composed primarily of hydrocarbon chains that are extremely combustible, directly producing CO2.

The two biggest sources of CO2 are energy and transportation, in that order. As expected the United States is the second highest in yearly emissions at 4997.5 million metric tons in 2015, behind China at 9040.71 million metric tons of CO2. If you were to calculate emissions per capita, the United States would be more than double China! This is due to several factors: China has a larger population, and many of them lead rural and agricultural lifestyles, and the society we live in is very wasteful.

The other big culprit of the greenhouse effect is methane. Methane (CH4) is less studied than carbon dioxide and because of this it is debated even within the climate science community but many scientists believe that although it’s effects last for less time than CO2 (several hundred years compared to several thousand) methane is more potent in regard to greenhouse properties. Due to the lack of research, methane is sometimes omitted in climate change models which makes many models an underestimate of the severity of climate change within the upcoming years.

Methane, and the nitrous oxide (N2O) another greenhouse gas, is mainly produced by the agriculture industry. Almost two thirds of all methane comes from agriculture and although the oil and gas industry is still the biggest driver of greenhouse gas input, the agriculture industry is second. This is a problem because although many governments and organizations are putting restrictions on fossil fuel companies, the agriculture industry has received very little restrictions to limit their methane output.

The greenhouse gases are the main drivers behind climate change and one of the best ways to stop it is to cease our input of greenhouse gases. The best way to do this is to invest in renewable energy. Renewable energy is a process that is completely sustainable that could power our globe forever. My next two blogs will be on types of renewable energies and how they are being used across the planet and in our backyard.