Adaptation: Process of adjustment to actual or expected climate and its effects. In human systems, adaptation seeks to moderate or avoid harm from climate change or exploit beneficial opportunities.
Vulnerability: The propensity or predisposition to be adversely affected. Vulnerability encompasses a variety of concepts and elements including sensitivity or susceptibility to harm and lack of capacity to cope and adapt.
Impacts: Effects of extreme weather, climate events and climate change on natural and human systems. Impacts generally refer to effects on lives, livelihoods, health, ecosystems, economic, social and cultural assets, services (including environmental services) and infrastructures due to the interaction of climate changes or hazardous climate events occurring within a specific time period and the vulnerability of an exposed society or system. Impacts are also referred to as consequences and outcomes. The impacts of climate change on geophysical systems, including floods, droughts and sea level rise, are a subset of impacts called physical impacts.
Risk: Potential consequences when something that is considered valuable is at stake and the outcome is uncertain. Risk is often expressed as the probability of occurrence of a hazardous event or the product of trends in the impacts should those events or trends come to pass.
Mitigation (of climate change): Human intervention to reduce the sources or enhance the sinks of greenhouse gases.
Resilience: The capacity of social, economic and environmental systems to cope with a hazardous event or trend or disturbance, responding or reorganizing in ways that maintain their essential function, identity and structure, while also maintaining the capacity for adaptation, learning and transformation.
(Sources: IPCC, MITECO and PNACC)