Glossary

 
Adaptation
 
Actions to reduce the vulnerability of natural and human systems to climate change effects. For instance, an adaptation action that can be taken to reduce the damaging effects of rising sea levels is to build higher sea defences. Various types of adaptation exist, e.g. anticipatory and reactive, private and public, and autonomous and planned.
 
 
AR4
 
The Fourth Assessment Report of the IPCC, released in 2007.
 
 
Baseline
 
The reference against which change is measured, e.g. ‘baseline climate’ is normally defined as the period 1961-1990.
 
 
Carbon dioxide (CO2)
 
CO2 is a naturally occurring gas, and a by-product of burning fossil fuels or biomass, of land-use changes and of industrial processes. It is the main greenhouse gas produced by man that is driving climate change.
 
 
Climate change
 
Climate change refers to any change in climate that lasts for an extended period, typically decades or longer, whether due to natural variability or as a result of human activity. 
 
 
Climate hazards
 
Climate variables which have consequences for the system being studied (in this case, Albania’s energy sector). The main climate hazards to be discussed at the workshop are temperature, precipitation, relative humidity, sunshine, winds, sea level rise and extreme events such as storms.
 
 
Climate impacts
 
The effects that climate hazards have on a given system (in this case, Albania’s energy sector), e.g. reductions in rainfall have impacts on hydropower generation.
 
 
Climate variability
 
Climate variability refers to variations in the average state of climate. Rainfall, for instance, has high natural variability, which makes it difficult to detect a climate change signal.
 
 
General Circulation Models / Global Climate Models (GCMs)
 
A computer-based numerical model of the climate system. GCMs are developed and run by climate modelling centres around the world and are used to project changes in climate.
 
 
Greenhouse Gases (GHGs)
 
Greenhouse gases absorb and emit infrared radiation. This property causes the greenhouse effect. Water vapour (H2O), carbon dioxide (CO2), nitrous oxide (N2O), methane (CH4) and ozone (O3) are the primary greenhouse gases in the earth’s atmosphere.
 
 
Intergovernmental Panel on Climate Change (IPCC)
 
The Intergovernmental Panel on Climate Change was formed in 1988 by the World Meteorological Organization (WMO) and the United Nations Environment Programme (UNEP), and is the international advisory body on climate change.
 
 
Mitigation
 
Actions to reduce man-made effects on the climate system. These include actions to reduce emissions of greenhouse gases (such as energy efficiency measures or the use of renewable energy resources), as well as actions to increase greenhouse gas sinks (such as planting forests).
 
 
Risk
 
Risk is the product of the likelihood (or probability) of an eventoccurring and the magnitude of its consequence.
 
 
Scenario
 
A plausible description of how the future may develop. Scenarios are not predictions or forecasts, but are useful to provide a view of the implications of actions.
 
 
Sensitivity
 
Sensitivity is the amount by which a system is affected, either adversely or beneficially, by climate variability or climate change. For instance, the efficiency of gas turbines is sensitive to temperature. As temperatures rise, efficiency falls.
 
 
Special Report on Emissions Scenarios (SRES)
 
To provide a basis for estimating future climate change, the IPCC prepared the Special Report on Emissions Scenarios in 2000. It provides 40 greenhouse gas and sulphate aerosol emission scenarios based on different assumptions about demographic, economic and technological factors. The emissions scenarios are fed into Global Climate Models, to project future changes in climate.
 
 
Threshold
 
A property of a system where the relationship between the input and the output changes suddenly. For example, the height of a flood defence represents a critical threshold – if water levels exceed the defence height, flooding will occur. It is important to identify climate-related thresholds as they indicate rapid changes in the level of risk.
 
 
Timeslice
 
Projections of climate change are usually given for three timeslices – the 2020s, 2050s and the 2080s. The projections are a 30-year average, centred around each of the given timeslices, (i.e. the 2020s is 2010 – 2039). Climate models cannot predict what the specific climate will be in any given year, due in part to the inter-annual variability of climate variables, so the projections are 30-year averages of future climate.
 
 
Uncertainty
 
An expression of the degree to which a value is unknown (e.g. the future state of the climate system). Uncertainty can result from lack of information or from disagreement about what is known or even knowable.