No doubt our world is in the midst of climate change and our earth is getting warmer. With these changes potential costs and hardships could be devastating in worse case scenarios. Science has warned us of apocalyptic scenes involving rising oceans, water shortages and volatile climate systems prone to severe weather. Indisputably our industrious greenhouse gas emissions are correlated to trends in climate change. Take a look at this graph on the right. For the past 800,000 years world temperature have risen and fallen in significant correlation with rises and falls in atmospheric carbon dioxide concentrations. The CO2 concentrations have ranged between 200-280 PPM. Currently CO2 concentrations hover just below 400 PPM, higher than any concentration seen in the past 800,000 years.
Has the earth ever witnessed concentrations this high? Should this spark any fear? The answer may surprise you but paleoclimate scientists looking at historical climate trends reveal that our earth has experienced numerous swings in carbon dioxide and temperature. The Pliocene between five million and three million years ago is the most recent geologic era that had CO2 concentrations similar to ours. Quoting an article from Scripps Institution of Oceanography UCSandiego:
Recent estimates suggest CO2 levels reached as much as 415 parts per million (ppm) during the Pliocene. With that came global average temperatures that eventually reached 3 or 4 degrees C (5.4-7.2 degrees F) higher than today’s and as much as 10 degrees C (18 degrees F) warmer at the poles. Sea level ranged between five and 40 meters (16 to 131 feet) higher than today.
There is broad consensus among paleoclimate scientists, that the earth has even experienced CO2 concentrations substantially higher than today, but in a larger scale of tens of millions of years ago. So whats the big deal with climate change? Are there reasons for concern? Whats the difference between climate change today and climate changes of the past?
Even though the earth has experienced global warming many times in it’s geologic past, there are several critical differences between these past climates and the human induced climate change we are in now. First of all, geologic changes in climate take place on a geologic time scales where a change of 10 ppm could take a thousand years. Currently the at projected rates of emissions we could reach 1000 PPM in the next hundred years (http://keelingcurve.ucsd.edu/what-does-400-ppm-look-like/ ). The radical change in such a short period of time leaves climate scientists guessing what will happen exactly in the short and longterm. Earth’s heat transfer system could be tipped out of its equilibrium state from dramatic shocks in overall CO2 concentrations today. While today the effects of this shift may not be seen, snowballing positive feedback loops will accelerate climate changes and swing them into a new climate plateaus. The question is how far will the effects reach? How does this threaten our geographic distribution and environment? Do we have the responsibility to mitigate or alter our current course?
Despite the uncertainty of outcomes, we still have a chance today to influence our future. Our undying need for energy in our technocapitalist certainly stokes the problem. Energy demands are only increasing as more countries start developing and as technology becomes more apart of our lives. Fossil fuels power our growing nations and economies, but their emissions drive a volatile storm on our not too distant horizon. In addition, the lengths to which we go to extract these fuels threatens the environment, air and water supplies. On top of all this fossil fuels are non-renewable energy source.
Lets face it, carbon emissions pose substantial threat to our environment, and the world we know and love today. While they are the cheapest energy source, with the most existing infrastructure, their external costs are ignored in the equation of cost. Economics would say that, these external costs will eventually be factored in by the actions of a free market. Eventually in the case of fossil fuels, is taking too long. If the free market wasn’t so short sighted in cost evaluations, renewable energies even at current cost, could be cheaper.
So what? What are our options? We need a combination of ground breaking policy and ground breaking technology. We need the true costs of fossil fuels to be recognized while innovating to make renewables cheaper and practical to implement. Maybe carbon credits/taxes are the solution by incentivizing industry to clean up their act while at the same time bumping up the price of fossil fuel generated energy. On the flipside, the only way renewables can compete against fossil fuel is through drastic innovation and upheaval of existing infrastructure.