Climate change and adaptation to the changes in climate is a subject widely covered by the popular media as well as various fields of science. Climate change has become a major global environmental challenge and one of the most acute issues of the twenty-first century. The climate of the world varies from one decade to another, and a changing climate is natural and expected. However, there is a well-founded concern that the unprecedented human industrial and development activities of the past two centuries have caused changes over and above natural variation.
The International Panel on Climate Change (IPCC) defines climate change as a change in the state of the climate that can be identified (e.g. by using statistical tests) by changes in the mean and/or the variable properties, and that persists for an extended period, typically decades or longer. Climate change may be due to natural
internal processes or external forcings, or to persistent anthropogenic changes in the composition of the atmosphere or in land use. Article 1 of the United Nations Framework Convention on Climate Change (UNFCCC) defines climate change as a change in the climate which is attributed directly or indirectly to human activity that alters the composition of the global atmosphere and which is in addition to natural climate variability observed over comparable time periods.
11.1 The causes of climate change
The global climate system is driven by energy from the sun. Several gases in the atmosphere act to trap the energy from the sun, thus warming the earth. These gases are called greenhouse gases and the process is known as the greenhouse effect. Without this process, there would be no life on earth. Human activities over the past 200 years, particularly the burning of fossil fuels (oil, coal, natural gas) and the clearing of forests, have increased the concentration of greenhouse gases in the atmosphere. This is likely to lead to more solar radiation being trapped, which in turn will lead to the earth's surface warming up, called the enhanced greenhouse effect (WeatherSA, 2003).
11.2 Increasing vulnerability through climate change
An increase in climate change has far-reaching effects globally. Through climate change certain areas around the globe will record an increase in natural deforestation, a rise in sea levels and deceasing crop levels. Climate change further influences weather patterns which could cause an increase in the frequency and severity of cyclones. An influence on different surface water resources will also be felt which could lead to conflict and an increased risk of diseases. All of the above contribute to an increase in vulnerability within communities already at risk.
11.3 Climate change and disaster risk
It is important to understand the effects of climate change on the risk of disaster.
Climate change in itself should not be viewed as a hazard. Rather the changes in climate affect climatic patterns and the cycles of the Earth leading to increases in frequency and intensity of various natural hazards. Climate change therefore affects disaster risk through the increase in weather and climate hazards and, second, by increasing a community’s vulnerability to these natural hazards. The latter takes
place through a degradation of the ecosystem, a reduction in the availability of water and food, and a change in livelihoods. In addition to environmental degradation and rapid unplanned urban growth, climate change adds additional stress that will further reduce the ability of a community to cope with existing climate hazards. However, climate change may also have some “positive” consequences, such as longer growing seasons and lower natural winter mortality. The likelihood of a future increase in climate extremes also raises the concern that climate-related disasters will increase in number or scale and it is therefore vital to address the vulnerability of communities.
11.4 Climate change adaptation
A valid question to ask is: How do we reverse this situation? There are quite varied opinions and scientific evidence to suggest either that the current process is irreversible, or that we as humans can still do something about climate change. It is not the aim of this text to justify or investigate either of these viewpoints but rather to put climate change in the context of disaster risk reduction. Doing so means that one must look at the “precautionary principle” which is linked to climate change adaptation.
The Precautionary Principle is applied in situations where the outcome of our actions are unknown (or consensus on the outcomes of certain actions has not been reached) or not proven through scientific enquiry. This means that in the event that we suspect that our actions could lead to harm, we have a social responsibility to protect the public from this exposure. In the case of climate change we need to err on the side of caution. Thus, it makes more sense to rather choose a less risky course of action (e.g. trying to reduce greenhouse gases), than not (e.g. having an endless debate on whether we as humans are in actual fact causing climate related change).
Climate change adaptation is the human’s response to the changing climate. Such actions are aimed at reducing vulnerability to climate change and securing livelihoods. Humans’ ability to adapt to climate change is distributed unevenly throughout the world. Just as it is the poorest of the poor who have most vulnerability to disaster risks, it is also this specific group of people who will have to carry the
brunt of climate change related impacts. Ironically it is also this group that contributes the least to the effects of climate change.
One should, however, not make the mistake of thinking climate change adaptation is something new or novel. Humans have been adapting to their natural environment since time began. Climate change affects all of the vulnerability domains we discussed earlier. It has the potential to significantly impact and change these domains which are crucial to sustain life. Climate change should thus be seen for what it is, a change agent. Disaster risk reduction measures should therefore seriously consider climate change but do not require all brand new actions by humans. Issues of climate change and adaptation must be incorporated into our understanding of disaster risks.