Climate change is an issue that is hard to ignore; the evidence certainly points to it happening. A recent report by Climate Communication indicated that over the last decade there have been twice as many heat waves as extreme low temperatures and if the Earth was neither warming nor cooling, there should be a similar number of both events. However, there is a heated debate around whether the climate change we are currently seeing is part of the Earth’s natural cycle of warming and cooling, which has been repeated time and again over our planet’s history, or whether human activity has largely been the contributing factor. There is no denying that over the last century huge amounts of greenhouse gases have been released into the atmosphere. Although carbon dioxide levels have mainly risen as a consequence of burning fossil fuels, deforestation has also reduced the amount of carbon dioxide removed from the atmosphere and methane levels have also risen due to more intensive farming. The theory is that carbon dioxide, methane and the other greenhouse gases form a blanket around the Earth, trapping energy and causing warming.
Evidence and consequences of climate change
Over the last century the average global temperature has risen by 1.4?F. While this may not sound a big change and many people are dubious about global warming – a Gallup Poll in 2011 showed that half of the Americans questioned felt that the extent of global warming was exaggerated – scientists predict temperatures could rise by up to 11.5?F by 2100. With this temperature rise the impact on the environment would be immense. Melting ice caps are already contributing to rising sea levels; in the 20th century sea levels rose by an average of 18cm, with a further rise of between 50 and 100cm expected within the next 100 years, flooding many areas of the world. However, rising temperatures also impact on rainfall. Although global rainfall is set to increase by 1-2% – higher temperatures cause more water to be evaporated and the atmosphere is able to hold more water when it is warmer – there will be local variation, with some areas of the world becoming drier such as the southern states of the United States and central and southern Europe. Changes in precipitation will impact on agriculture, but also our forests, with this year’s forest fires having been testament to this.
Forest fires – the impact of climate change
This summer across the world forest fires have been raging. Millions of acres of forest have been destroyed in western areas of the United States; in California alone 500,000 acres of forest were devastated. Colorado was another state hit hard by forest fires. Here, a combination of soaring summer temperatures, low rainfall, reduced snowfall and early thaw last winter, are all the climatic factors thought to have contributed. Not only are the dry trees and undergrowth very likely to catch fire, but tree death as a consequence of drought and insect attack makes them more vulnerable still. Forest fires don’t just destroy habitats and alter landscapes, but they further increase the release of carbon into the atmosphere; people living near affected areas are also forced to flee their homes and fatalities also occur. A study by researchers at the University of California has shown that in the last 25 years the number of forest fires has increased, but also the size of the area that they cover and the intensity at which they burn. As climate change deepens we can expect the number and scale of forest fires to escalate.
Forest fires – the contribution of human activity
Although climate change has an important role to play, human contribution to forest fires can’t be ignored. During the last 20 years in Colorado, 250,000 people have moved into the so-called fire-prone zones and the more people there are in these areas, the more risk of fire occurring. It’s important to remember a lot of fires are started as a result of human activity – a discarded cigarette end, a careless BBQ or a down power line can all ignite a fire, then there is the small number of fires started deliberately. Once burning, people’s homes can act as fuel, facilitating the further spread of fires. Human related factors are also thought to have contributed to European forest fires. Spain’s fires, which were the worst seen for a decade, were aided by reduced grazing of animals, providing extra undergrowth to burn; a reduced budget for fire fighting also made the blazes more difficult to control. Meanwhile, in Bosnia the spread of fire was enhanced by minefields remaining from the Balkans War in the 1990’s. Rumours also suggest that some of the forest fires in Greece were started deliberately by property developers to clear areas of land for housing.
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Betty is a health writer for a magazine that delivers information not just on quitting but on harm reduction for those who are not yet ready or able to quit.