Acute – Occurring over a short period of time (as opposed to chronic).
Adaptation – The process of adjustment to actual or expected climate and its effects. In human systems, adaptation seeks to moderate or avoid harm or to exploit beneficial opportunities. In some natural systems, human intervention may facilitate adjustment to expected climate and its effects (IPCC, 2014).
Adaptation mainstreaming – Integrating climate change adaptation considerations and information into policies, programs, and operations at all levels of decision making rather than creating new policies or policy instruments. The goal is to make the adaptation process an essential component of existing decision making and planning frameworks (adapted from UNDP, 2005).
Adaptive capacity – The ability of systems, institutions, humans, and other organisms to adjust to potential damage, to take advantage of opportunities, or to respond to consequences (IPCC, 2014).
Aerosols – A collection of airborne solid or liquid particles with a typical size of 0.01 to 10 mm that reside in the atmosphere for at least several hours. Aerosols may be of either natural or anthropogenic origin. Aerosols may influence climate in two ways: directly through scattering and absorbing radiation, and indirectly through acting as condensation nuclei for cloud formation or modifying the optical properties and lifetime of clouds (IPCC, 2001).
Air Quality Benefits Assessment Tool (AQBAT) – A computer application designed by Health Canada that provides economic valuation estimates of health impacts of air quality, considering the potential social, economic, and public welfare consequences of the health outcomes, including medical costs, reduced workplace productivity, pain and suffering, and increased mortality risk (Government of Canada, 2020).
Albedo – The fraction of solar radiation reflected by a surface or object, often expressed as a percentage. Snow-covered surfaces have a high albedo; the surface albedo of soils ranges from high to low; vegetation-covered surfaces and oceans have a low albedo. The Earth’s planetary albedo varies mainly through differences in cloudiness, snow, ice, leaf area and land cover changes (IPCC, 2007).
Anomaly – Departure from the average over a reference period (Bush & Lemmen, 2019).
Anthropogenic – Resulting from human activities or produced by human beings (IPCC, 2007).
Atmosphere – The gaseous envelope surrounding the Earth. The atmosphere consists almost entirely of nitrogen and oxygen, together with a number of trace gases such as argon and helium, and greenhouse gases such as carbon dioxide and ozone. In addition, the atmosphere contains water vapour, clouds, and aerosols (WHO, 2003).
Attribution (science) – Identifying the causes of an observed change or event in terms of the relative contributions of multiple causal factors (Bush & Lemmen, 2019).
Autochthonous – Formed or originating in the place where it is found.
Baseline – The baseline (or reference) is the state against which change is measured. A baseline period is the period relative to which anomalies are computed (IPCC, 2014).
Black carbon – Commonly known as soot. An aerosol that is emitted as a result of the incomplete combustion of carbon-based fuels. Black carbon absorbs solar radiation and has a warming effect. It is termed a short-lived climate pollutant given it remains in the atmosphere only for days or weeks (IPCC, 2018).
Burden of disease – The burden of disease can be thought of as the measurement of the gap between current health status and an ideal health situation where the entire population lives to an advanced age, free of disease and disability (UNEP, 2018).