Q: The average global temperature has dropped two degrees in the past two years. Crop yields are projected to decline 10 percent in 2009 due to cooler growing conditions. Approximately 85 percent of CO2 is not from man-made sources. Countries outside the United States produce the majority of CO2 and their growth rate is accelerating. If global warming is actually due to man, rather than sunspots or other natural causes, how can the current efforts to minimize CO2 emissions before we have replacement technology be cost justified?
Asked by Daniel Wildermuth, ’87, Alpharetta, Ga.
I'm going to be frank: global warming, climate change, whatever you want to call it—is real. There is no debate amongst the scientific community on this point. In a 2004 study published in Science, Naomi Oreskes examined all the peer-reviewed scientific articles about global climate change published between 1993 and 2003, and not one of those 928 articles rejected the consensus position that the Earth's climate is changing due to man.
However, not everyone subscribes to scientific thought. After Oreskes's article was published, a climate skeptic, Benny Peiser, attempted to publish a similar study showing that three percent of all articles on global climate change rejected the consensus position. He submitted it to Science as well, but it was not accepted because the only articles he could find to defend the climate skeptic position were not peer-reviewed scientific articles. Basically, the only support for rejecting climate change comes from a bunch of unscientific opinion articles.
Science operates by something called "preponderance of evidence." Science is not so naïve as to take anything as fact, because that would require that one knows absolutely everything—an impossibility. Rather, science operates by gathering evidence, through experimentation or observation. The theory supported by the most evidence is generally accepted as being the most likely explanation. The evidence for climate change is so strong, and comes from so many different lines of theory and evidence, that not a single scientific article as far back as 1993—when climate science was still in its infancy—has refuted it.
So what's up with all these rumors about global cooling? Well, as Verlyn Klinkenborg, the environmental editorial voice of the New York Times would say, "we're dealing with the impenetrability of the American mind to scientific thought." A lot of Americans simply do not believe in climate change and, therefore, climate science. The Pew Research Center for People and the Press recently conducted a poll of Americans on climate change, and they found that 33 percent of Americans do not believe in global warming. That's 12 percent more than the same survey conducted in 2008. Americans, it would seem, are not warming to the science of global warming.
Worse yet, of the 57 percent of Americans who believe there is evidence for global warming, 28 percent of those believe it is due to natural patterns. Only 36 percent of Americans believe the scientific consensus on climate change. Where are the other 64 percent of Americans getting their facts from? They're most likely getting it from personal experience, which, as I pointed out in the essential answer is not a good indication of climate change patterns, since daily, seasonal and yearly patterns of weather change are much more noticeable to individuals. The problem with climate change is that it operates on time scales that humans simply do not comprehend in a day-to-day sort of way. That is why scientific inquiry is the only reliable means of examining climate change.
According to the Nobel prize-winning Intergovernmental Panel on Climate Change, a UN-sponsored scientific body charged with evaluating the risk of manmade climate change, the probability that the change we have seen in the world climate is due to natural causes is less than five percent. That is to say, the warming of the world's climate is unequivocal and the warming is caused by man.
It's true that the majority of the world's carbon emissions do not come from the United States, but then again, why should they? The United States does not have the majority of the world's population. The United States was recently supplanted by China as the world's largest emitter of carbon dioxide, although the United States remains a close second. In 2006 both countries emitted about 20 percent of the world's greenhouse gases through the burning of fossil fuels; but, while China has 20 percent of the world's people, the United States has just 4.5 percent. Americans (and those in many other developed nations) are emitting grossly out of proportion with the world average per capita emissions.
The reason why scientists—and now governments—are so concerned about these emissions is because they threaten the balance of the Earth ecosystem as we know it. Sea level rise due to melting ice caps threatens to submerge coastal areas and entire island nations. Species are already going extinct because of the habitat changes brought by climate change. Changing climatic conditions threaten decreased food production, increased storm severity and the spread of tropical disease.
While developed countries such as the United States produce the majority of the greenhouse gases per capita, the effects will mostly hurt poor countries that cannot afford to pay higher food prices or countries that could soon find themselves completely underwater, such as the Maldives.
Carbon Emissions Around the World
Carbon Dioxide Emissions from the Consumption and Flaring of Fossil Fuels, 2006. The most recent world carbon dioxide emissions data from the Energy Information Administration (U.S. Department of Energy) shows China has overtaken the United States as the largest producer of carbon dioxide emissions from fossil fuels. The top four countries—China, the United States, Russia, and India—produced 51 percent of the world's carbon dioxide emissions in 2006.
List of the top 4 countries by 2006 CO2 emissions
|Rank||Country||Annual CO2 emissions
(in millions of
|2||United States||5,903||20.2 percent|
Sources: Nicholas Jachowski (author) made the pie chart and table using data from the Energy Information Administration.
Why Should You Care?
If the suffering of millions doesn't do it for you, how about self interest? You should also care because if you don't jump on the climate change bandwagon you stand to miss out on the next great wave of technology and business innovation. Cleantech. Greentech. Renewable energy. Sustainability. This new wave of development is already helping to tackle the greatest problem of our time. How can this be cost justified, you ask? Well, how can it not be? There are profits to be made, and if we don't take action now, it'll be the Chinese and the Germans and everyone else making them. And how do you justify that? But even if you don't care about profits, there is something for you in the climate change mitigation movement: cleaner air, a healthier planet, more jobs and a better life—for you, for your children and for all those who will come afterward.
Here's another way to look at it: What do we save by not mitigating climate change? We merely pass on more problems to the next generation. Scientists say that even if we were to stabilize emissions at current levels the world would continue to warm and sea would continue to rise for centuries. If we don't act now, when we still have a chance to prevent some of the consequences of global warming, we'll have to spend a lot more in the future to try to reverse the damage. And eventually the damage will be too great to reverse.
I suppose we could give up. This is a problem we cannot solve, you might argue. But that would be a lie. We have the technology to be more efficient with our energy use. We have cleaner transportation methods. We have alternative energy technologies. What we need now is financial and regulatory support for these technologies to gain a foothold in the world; because right now they're battling subsidized dirty energy whose price doesn't reflect the full cost of their impact on the Earth.
Even the oil companies know renewable energy is the future. British Petroleum has become Beyond Petroleum, and is investing $500 million in new biofuels. Shell oil is also investing heavily in biofuels.
It's true that the changes society will need to make as we shift toward low-carbon fuels will not be easy. But ultimately, we don't have a choice. The world will still warm, whether 64 percent of Americans believe it's the result of humans burning fossil fuels or not. And the world will still shift to green technologies whether the United States is on board or not. As for me, I'm going to help make it happen, and I hope you will too. Because Earth can use all the help it can get right now.
Nicholas Jachowski plans to receive his bachelor's and master's in earth systems in 2010.