What is climate change?
Climate is the average weather experienced over a long period of time. Climate change is the long-term change in these average weather conditions. The earth’s climate has changed many times over thousands of years in response to natural causes, such as solar activity, variations in the earth’s orbit, volcanic eruptions, changes in ocean currents, glacial and interglacial cycles, and so on.
However, over the last century, the planet has warmed by about 0.8 degrees Celsius. Scientific research establishes that this anomalous level of warming is well out of the range of the earth’s normal temperature variations as far back as we can measure. The scientific consensus also proves that the intensity of warming, which has increased dramatically in the last half century, cannot be explained by natural causes, but does correlate with increased carbon dioxide emissions from burning fossil fuels.
What are greenhouse gases and the greenhouse effect?
The greenhouse effect is the natural process by which the atmosphere traps some of the sun’s energy, warming the earth enough to support life. It works because certain gases in the atmosphere (water vapour, nitrous oxide, methane and of course carbon dioxide) trap the sun’s energy, without which heat would escape back into space.
Since the industrial revolution in the eighteenth century, humankind has become increasingly dependent on the burning of fossil fuels, primarily coal, gas and oil, to drive the economic growth of industrial societies. As growth has continued exponentially until today, so has the exploitation of the world’s fossil fuel resources, resulting in the escalation of carbon dioxide emissions. As the atmospheric concentration of carbon dioxide increases, it is overwhelming the earth’s natural carbon cycle, trapping more heat, and thus amplifying the natural greenhouse effect.
This is why trees are so important. Trees breathe in carbon dioxide and breathe out oxygen.
What are the potential consequences of climate change?
Without effective action to halt fossil fuel emissions and reduce the atmospheric concentration of greenhouse gases, all species on earth face a bleak future. Around the world, seasons are shifting; temperatures are climbing, and sea levels rising. Climate scientists predict that within coming decades, without major change, large areas of the planet would face permanent drought, while other areas would suffer from excessive floods. The rainforests could collapse into raging fires, while agriculture fails due to extreme temperatures, and oceans become acidified. We are already seeing the effects now – scientists acknowledge that the frequency and severity of floods, storms, droughts, heat-waves and other natural disasters is increasing.
Current fossil fuel emissions fit the UN Intergovernmental Panel on Climate Change’s (IPCC) worst-case scenario projecting that without drastic change, global average temperatures would rise as much as 6 degrees Celsius. At such a level of warming, there would be sweeping mass extinctions, and much of the earth would be virtually uninhabitable.
It is no surprise then that we are already experiencing some of the devastating effects of climate change. In Pakistan, as of August 2010, devastating floods have resulted in the deaths of more than 1600 people, and the displacement of 14 million in the country’s worst natural disaster ever.
Low-lying Bangladesh and the neighbouring region is prone to coastal flooding caused by storm surges, which have killed thousands of people in recent years. According to experts, if the sea level rises by 1 metre, Bangladesh will lose 17.5 per cent of its land – yet many scientists project that sea levels could rise by 2 meters toward the end of the century (and rise continuously after that).
In the UK, experts predict that fierce storms and floods – such as those that brought parts of the UK to its knees in October 2007 – are likely to become more frequent in the future.
Scientists have also shown that global warming has already been responsible for increasing droughts, particularly in food-basket regions, in Australia and Africa.
Climate change and poverty
The world’s poorest people are also the least responsible for climate change, with the least developed countries contributing only 10 percent of annual global carbon dioxide emissions. Although the countries most responsible for global warming are the world’s wealthier, industrial societies of the North, those most vulnerable to the worst effects of climate change live in the poorer, less developed countries of the South – that is up to 5 billion people.
Out of these, 3 billion people live below the internationally-recognized poverty line. The poor, lacking access to resources and services, are less able to adapt to a changing climate, and far more vulnerable to its dangerous impacts. Diseases, declining crop yields and natural disasters are just a few of the ways climate change could devastate the world’s most vulnerable communities.
Can climate change be reversed?
Some changes to our climate may already be inevitable given the historic build up of emissions in the atmosphere, but it is not yet too late to avert the worst possible scenarios. Immediate, urgent action is necessary to save the planet and protect LIFE. The longer we wait to act, the greater the probability that various climate changes could lead to the irreversible collapse of key eco-systems, culminating in process of runaway global warming. One the most powerful ways to prevent this from happening is to plant trees. The more we reforest the southern hemisphere, the greater the resilience of poorer communities and the earth as a whole to global warming.