There is growing consensus among scientists and politicians that the global climate is changing. The main impact of these changes on humans and the environment is the availability and quality of water and increased exposure to weather-related natural disasters (World Water Assessment Programme 2009). Not only can climate change directly reduce the availability of water, but it can also have indirect impacts on other issues such as food security, loss of biodiversity and increased prevalence of disease.
These changes to the global climate system and the subsequent regional and sub-regional impacts are believed to be incited by anthropogenic (man-made) emissions of greenhouse gases (GHGs). The primary GHGs are carbon dioxide, methane, sulphur dioxide and nitrous oxide (IPCC 2008). Increases in population and development since the industrial revolution have lead to increases in atmospheric concentrations of GHGs, as demonstrated by research using ice-core drilling. Records developed from ice-cores dating back 10 000 years have been combined with more recent data collected since 1750 to compare increases in GHGs to background levels.
The climate changes reflect a general increase in global temperature and changes to the composition of the atmosphere, which in turn cause changes in precipitation, temperature and other atmospheric and weather-related patterns. The ultimate result is ongoing change in catchment rainfall-runoff processes and the availability of water, which will have a profound effect on ecosystems and the communities that rely upon them.
Climate Change Adaptation
With the general consensus having accepted climate change is occurring, the international research and policy is now shifting attention to climate change adaptation. While there are many varying definitions of climate change adaptation, the Intergovernmental Panel on Climate Change (IPCC) uses the following:
Definition of Climate Change Adaptation
“Adjustment in natural or human systems in response to actual or expected climatic stimuli or their effects, which moderates harm or exploits beneficial opportunities.”
IPCC 2007
Even if current efforts to reduce greenhouse gas emmissions are successful and average global temperature rises slow down, climate change is inevitable. Changes in climate are predicted to have wide-reaching consequences for many aspects of society, from availability of freshwater to agricultural productivity. These issues will have profound implications for human populations, particularly those living in already water stressed regions, such as southern Africa, where high demand and growing development issues combined with near basin closures increase vulnerability.
What is clear from current work in this area is that society as a whole will soon need to make fundamental changes in order to deal with the predicted impacts of climate change; from the individual level to infrastructure and policy.
The diagram below provides a high-level outline of the process of adaptation. It is important for governments to acknowledge the potential threat climate change poses and raise awareness of the issue through mainstreaming and education. Societal and political will must support the intent to act from national to local government level. Finally a range of adaptive actions must be taken, including a range of options that address demand, supply, culture and expectations.
The climate change adaptation process.
Source: Schulze 2008
( click to enlarge )
For further reading on climate change adaptation, please refer to GTZ 2009 and GWP 2007 in the Document Center.
