How Much Is Enough?

Most of us now realize that we need to do something about global climate change. We know that we have to reduce greenhouse gas emissions from fossil fuels such as oil and coal. But how much do we need to reduce emissions in order to prevent severe impacts on society and the environment? Most scientists and policy makers now believe that we need to keep prevent average global temperatures from rising 2°Celsius above pre-industrial levels Ok, what’s the big deal with the temperature going up a few more degree? Well, it may not seem like much, but the reality is that scientists project that even a 2°C increase in temperature will have very significant impacts on the climate. This is in part due to the fact that in certain areas, particularly the north and south poles, warming would be significantly more than 2°C.

The Intergovernmental Panel on Climate Change (IPCC) recently released their Fourth Assessment Report on climate change (www.ipcc.ch/). This international network of scientists conducts regular analyses of all the peer reviewed scientific data related to climate change. They look through studies from scientists across the globe to assess whether climate change is happening, what the projected impacts will be, and how we can address the problem. The latest assessment revealed that yes indeed global temperatures are rising, that this is caused by human greenhouse gas emissions, and that there will be significant impacts on our climate systems as a result of this warming. Projected impacts are more severe droughts, more severe flooding, rising sea levels, more intensive storms, and other changes. These climate impacts are projected to displace millions of people along coastal areas (coastal cities under water), cause disruptions in food and water supplies for people across the globe (food and water prices increasing, more starving people, and conflict over water supplies) , and result in increased destruction of communities due to severe weather events (Hurricane Katrina all over again).

While the scientific community has been fairly certain about this for quite some time, the IPCC’s Fourth Assessment Report is the most conclusive of their studies, showing that they are more certain than ever before about all of the science behind climate change. They know if we continue with business as usual there will be devastating consequences for the entire world, including the United States.

So again, how much action do we need to take? Scientists and policy makers believe that global greenhouse gas emissions need to peak in 2015. That means that our global warming pollution would need to be the highest in 2015 and then begin to decline steadily after that. They believe that the developed world (such as the US, European Union, etc) would have to reduce greenhouse gas emissions by 30% below 1990 levels by 2030 and then 80% by 2050. Similarly, global greenhouse gas emissions (including developing countries like China and India, and developed countries) would need to be reduced 50% by 2050. (The United States is currently emitting about 16% above 1990 levels, just to give you a sense of where we’re at.) These reductions require serious action and an enormous shift in the way we think about energy supply, industrial processes, transportation, agriculture, forest protection, and our own lifestyles.

Luckily, we have some of the world’s best innovators thinking very hard about how we’re going to solve this problem. There have been thorough studies about how we can tackle each sector such as energy, transportation, agriculture, etc, in order to reduce our emissions in both the developed and developing world.

People are also examining how we’re going to pay for these changes in our infrastructure. Interestingly, a recent study conducted by McKinsey&Company, a global management consulting firm, found that the United States could reduce emissions by 50% with very little cost to the economy (www.mckinsey.com). This is because many of the emission saving measures would also save a significant amount in energy costs. The McKinsey&Company study shows that these money saving measures could pay for the other emission reduction measures with very little net cost to the US economy. This is very good news considering the drastic cuts in emissions that are needed to solve this very urgent problem. So, now that we know how to reduce our emissions and how to pay for it, what’s stopping US?