By Jack Eardley
After the Paris Climate change accords, it would seem that the world, with the notable exception of President Trump, has agreed that climate change is real, humans are responsible, and reducing carbon is the solution. But is climate change really that simple?
Last Thursday, Student Energy Durham hosted Chartered Energy Engineer Andrew Clarke to discuss the wide range of contributors to climate change and rethink some common misconceptions.
Mr. Clarke focused his talk on both the anecdotal evidence that often features in news, as well as the hard data that climate scientists present as irrefutable evidence.
The first common confusion that he tackled was the distinctionbetween weather and climate. Put simply, Mr. Clarke explained that weather change happens in days and climate change happens in decades.
Aiming his comments towards President Trump and climate change sceptics, he explained that global warming does not mean that everywhere gets hotter, going on to explain that extreme weather conditions are predicted and already being seen in some parts of the world.
Melting sea ice is not just a symptom of climate change but a cause.
Although we may be experiencing colder winters, increasing the risk of hypothermia in Chicago and freezing iguanas in Florida, the global temperature is clearly rising. Mr. Clarke showed that climate change, and average global warming, is happening, and it’s happening now.
Many factors can influence global climate and these factors fall broadly into two categories. One cause is the production of gases that contribute to the greenhouse effect and reflect solar energy back to Earth from the atmosphere. Another issue is that these gases change how much sunlight the surface of the Earth can absorb to warm itself. Often, climate change causes are not simple and can have competing effects.
Melting sea ice, for example, is not just a symptom of climate change but a cause. An increase in global temperatures can cause ice to melt into water, this water is then better at absorbing sunlight than the ice, which results in increased temperatures and more ice melting. Such a vicious cycle is a mechanism often cited as a reason climate change may be irreversible.
Felled forests are simply left to decay and release their carbon back into the atmosphere, exacerbating the problems deforestation causes.
Deforestation of the Amazon for cattle rearing reduces the number of trees, which naturally capture carbon dioxide, on the planet. This deforestation is unwelcome or illegal and, as a result, it is often impossible for loggers to sell the trees they chop down for construction purposes. Thus these felled forests are simply left to decay and release their carbon back into the atmosphere, exacerbating the problems deforestation causes.
Near the end of the lecture, Mr. Clarke concluded that carbon dioxide and other greenhouse gases are the most likely cause of climate change, based on the best available climate data. Unusually though, he claimed that regardless of whether carbon dioxide is to blame or not, we should be taking steps to reduce it.
Not only does increased carbon release cause ocean acidification, which could endanger thousands of aquatic species, but continually burning oil will prevent it being used for its many other industrial and medicinal applications. Mr Clarke claimed he was not anti-oil but against wasting oil.
The overwhelming reality of the data presented in this lecture proved that although other factors do effect the climate, it is man-made carbon that is the greatest problem and one that our generation must fix.
Photograph: Wikimedia Commons