What is adaptation and why adapt?

Historic climate variations and recent weather events (e.g. storms, droughts, floods, warming temperatures, and changing precipitation patterns) show the sensitivities of our social, economic and environmental systems to current climate, and thereby, along with projected changes in climate, signal the need for adaptation measures to deal with both the existing adaptation and projected vulnerabilities.

Negative climate impacts (threats or risks) result when events approach or exceed existing tolerance thresholds. Positive impacts (or opportunities) arise when previously limiting factors (e.g. thermal limits or snow/ice cover) no longer restrict development or activities. Thresholds are often defined based on past experience, so the projections of climate changes, including its variabilities and extremes, should be taken into account to prepare for a future that is robust to a changing climate. Is it possible to minimise the negative impacts and take advantage of any opportunities that arise?

Addressing the challenges associated with climate change requires limitation of the magnitude and rate of change, as well as dealing with impacts and opportunities.

Actions to reduce the sources or enhance the sinks of greenhouse gases are known as mitigation, and are essential if we are to avoid dangerous or unacceptable climate change. Irrespective of how successful mitigation efforts are, a degree of climate change is unavoidable. These changes will need to be addressed through adaptive actions.

Unavoidable climate change is a result of current and historic greenhouse gas emissions and the persistence of these gases in the atmosphere, as well as the slow but building response of the oceans to atmospheric warming. The delayed response of the oceans will result in temperatures and sea level continuing to increase for several decades (and in the case of sea level rise, perhaps several centuries).

Measures are needed to enhance our capacity to adapt (building adaptive capacity) and to minimise, adjust to and take advantage of the consequences of climatic change (delivering adaptation actions).

The Intergovernmental Panel on Climate Change (IPCC) define adaptation as:

“an adjustment in natural or human systems in response to actual or expected climatic stimuli (variability, extremes, and changes) or their effects, which moderates harm or exploits beneficial opportunities” (IPCC TAR, 2001).

Adaptation is an integral part of natural and human history – the continued viability and sustainability of many systems will be dependent on their ability to successfully adapt to future changes in the climate (mean, variability and extremes).