| Acronyms || Definition |
| Anomalies || Anomalies represent the departures of specific measurements and/or forecasts from their long-term climatological values. Anomalies describe how much a specific variable differs from its normal state. |
| Biosphere || The part of the Earth system comprising all ecosystems and living organisms, in the atmosphere, on land (terrestrial biosphere) or in the oceans (marine biosphere), including derived dead organic matter, such as litter, soil organic matter and oceanic detritus. More on Biosphere. |
| BC || Black Carbon - Operationally defined aerosol species based on measurement of light absorption and chemical reactivity and/or thermal stability. It is sometimes referred to as soot. BC is mostly formed by the incomplete combustion of fossil fuels, biofuels, and biomass but it also occurs naturally. It stays in the atmosphere only for days or weeks. It is the most strongly light-absorbing component of particulate matter (PM) and has a warming effect by absorbing heat into the atmosphere and reducing the albedo when deposited on ice or snow. More on BC. |
| C3S || Copernicus Climate Change Service |
| C4E || Clim4Energy project is one of the C3S projects. |
| Climate || Climate in a narrow sense is usually defined as the average weather, or more rigorously, as the statistical description in terms of the mean and variability of relevant quantities over a period of time ranging from months to thousands or millions of years. The classical period for averaging these variables is 30 years, as defined by the World Meteorological Organization. The relevant quantities are most often surface variables such as temperature, precipitation and wind. Climate in a wider sense is the state, including a statistical description, of the climate system. More on Climate. |
| Climate forecasts or Climate predictions || Climate forecast (or Climate predictions) is the result of an attempt to produce (starting from a particular state of the climate system) an estimate of the actual evolution of the climate in the future, for example, at seasonal, interannual or decadal time scales. Since the future evolution of the climate system may be highly sensitive to initial conditions, such predictions are usually probabilistic in nature. See also Climate projection, Climate scenario, Model initialization and Predictability. |
| Climate Models || A Climate Model is a numerical representation of the climate system based on the physical, chemical, and biological properties of its components, their interactions and feedback processes, and accounting for all or some of its known properties. The climate system can be represented by models of varying complexity, that is, for any one component or combination of components a spectrum or hierarchy of models can be identified, differing in such aspects as the number of spatial dimensions, the extent to which physical, chemical, or biological processes are explicitly represented, or the level at which empirical parameterisations are involved. Coupled Atmosphere-Ocean General Circulation Models (AOGCMs) provide a comprehensive representation of the climate system that is near or at the most comprehensive end of the spectrum currently available. There is an evolution towards more complex models with interactive chemistry and biology. Climate models are applied, as a research tool, to study and simulate the climate, and for operational purposes, including monthly, seasonal, and interannual climate predictions. More on Climate Models. |
| Climate projections || |
A Climate Projection is the simulated response of the climate system to a scenario of future emission or concentration of greenhouse gases (GHGs) and aerosols, generally derived using climate models. Climate projections are distinguished from climate predictions in order to emphasize that climate projections depend upon the emission/concentration/radiative forcing scenario used, which are based on assumptions concerning, for example, future socioeconomic and technological developments that may or may not be realised. More on Climate Projections.
They start in 1850.
| Clusters || 96 clusters are defined in e-Highway 2050 |
| CMIPx || |
Coupled Model Intercomparison Project, x corresponding to the number of the phase - Global model which consider interactions between all systems: atmosphere, ocean, ice, biosphere. More on CMIPs.
They started in 2005.
| COPxx || Conference Of the Parties |
| e-Highway 2050 || More on e-Highway2050. |
| ECEM || European Climatic Energy Mixes, one of the C3S projects |
| ECV || Climatologues agreed on a list of Essential Climate Variables: Global Horizontal Irradiation in W/m², Temperature at 2 m, Wind speed and wind direction at 10 m, Relative humidity in %. |
| Ensemble || is a collection of model simulations characterizing a climate prediction (or projection). Running a GCM model multiple times only changing the initial conditions can at times simulate extended periods of quite different climate change signals for a specified area. This is due to the natural variability of the climate system, and it is impossible to state which circulation change is more likely to occur in the future. |
| ENTSOE || Database |
| ERA || ERA5 was produced using 4DVar data assimilation in CY41R2 of ECMWF's Integrated Forecast System (IFS). adjERAI ? |
| CORDEX || |
Coordinated Regional Climate Downscaling Experiment.
Database of dynamic atmospheric models. Forçage des autres systems ocean, ice and biosphere. No retro-action: for instance, an hypothesis could be the melting of the Antartic ice and its impact on climate is explored, but no retroaction on the speed of melting of the ice is considered. Read more about EUROCORDEX. In particular, take a look to the limits of climate modeling on page 9 and on how to interpret regional climate projections on page 15.
| Extreme Weather Event || An extreme weather event is an event that is rare at a particular place and time of year. Definitions of rare vary, but an extreme weather event would normally be as rare as or rarer than the 10th or 90th percentile of a probability density function estimated from observations. By definition, the characteristics of what is called extreme weather may vary from place to place in an absolute sense. When a pattern of extreme weather persists for some time, such as a season, it may be classed as an extreme climate event, especially if it yields an average or total that is itself extreme (e.g., drought or heavy rainfall over a season). More on Extreme Weather Event. |
| GIEC / IPCC || |
/ Intergovernmental Panel on Climate Change
The IPCC assesses the scientific, technical and socio-economic information relevant for the understanding of the risk of human-induced climate change.
| GCMs || Global Climate Models (or General Circulation Models) are computer codes used to solve a set of mathematical equations describing the laws of physics relevant to the atmospheric and oceanic circulation, the distribution of heat and the interaction between electromagnetic radiation and atmospheric gases and aeresols. Climate models represent an implementation of our theoretical knowledge of the climate system, describing interconnections between processes. They consist of different modules describing the atmosphere, oceans, sea-ice/snow and the land surface, and represent the world in terms of boxes stacked next to and on top of each other. The values for temperature, motion and mass are solved in each of these boxes, based on well known physical laws. Read more on GCMs. |
| GHG || Greenhouse gases are those gaseous constituents of the atmosphere, both natural and anthropogenic, that absorb and emit radiation at specific wavelengths within the spectrum of thermal infrared radiation emitted by the Earth's surface, the atmosphere itself, and by clouds. 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. Moreover, there are a number of entirely human-made greenhouse gases in the atmosphere, such as the halocarbons and other chlorine- and bromine-containing substances, dealt with under the Montreal Protocol. Beside CO2, N2O and CH4, the Kyoto Protocol deals with the greenhouse gases sulphur hexafluoride (SF6), hydrofluorocarbons (HFCs) and perfluorocarbons (PFCs). More on GreenHouse Gases. |
| Hindcasts || A hincast (or retrospective forecast) is a forecast made for a period in the past using only information available before the beginning of the forecast. |
| Kyoto Protocol || The Kyoto Protocol to the United Nations Framework Convention on Climate Change (UNFCCC) was adopted in 1997 in Kyoto, Japan, at the Third Session of the Conference of the Parties (COP) to the UNFCCC. It contains legally binding commitments, in addition to those included in the UNFCCC. Countries included in Annex B of the Protocol (most Organisation for Economic Cooperation and Development (OECD) countries and countries with economies in transition) agreed to reduce their anthropogenic greenhouse gas (GHG) emissions carbon dioxide (CO2), methane (CH4), nitrous oxide (N2O), hydrofluorocarbons (HFCs), perfluorocarbons (PFCs), and sulphur hexafluoride (SF6)) by at least 5% below 1990 levels in the commitment period 2008 to 2012. The Kyoto Protocol entered into force on 16 February 2005. More on Kyoto Protocol. |
| NUTS || |
| RCMs || |
Regional Climatic Models. A limitation of global climate models (GCMs) is their fairly coarse horizontal resolution. For most impact studies, such as evaluation of the future risks of floods or some types of landslides, droughts etc., the society requests information at a much more detailed local scale than provided by GCMs. Simply increasing the resolution is often not feasible because of constraints in available computer resources. A viable alternative is to embed a regional climate model (RCM) of higher resolution in relevant part of the GCM domain. RCM are complementary to GCM by adding further details to global climate projections, or to study climate processes in more detail than global models allow.
Within the ECEM projects, 6 RCMS are driven by 5 GCMS
| RCPs || |
Representative Concentration Pathways are scenarios that include time series of emissons and concentrations of the full suite of greenhouse gases (GHGs) and aerosols and chemically active gases, as well as land use/land cover (Moss et al., 2008). The word representative signifies that each RCP provides only one of many possible scenarios that would lead to the specific radiative forcing characteristics. The term pathway emphasises that not only the long-term concentration levels are of interest, but also the trajectory taken over time to reach that outcome (Moss et al., 2010). RCPs usually refer to the portion of the concentration pathway extending up to 2100, for which Integrated Assessment Models produced corresponding emission scenarios. Extended Concentration Pathways (ECPs) describe extensions of the RCPs from 2100 to 2500 that were calculated using simple rules generated by stakeholder consultations, and do not represent fully consistent scenarios. Four RCPs produced from Integrated Assessment Models were selected from the published literature and are used in the Fifth IPCC Assessment as a basis for the climate predictions and projections presented in WGI AR5 Chapters 11 to 14: RCP2.6: One pathway where radiative forcing peaks at approximately 3 W m-2 before 2100 and then declines (the corresponding ECP assuming constant emissions after 2100); RCP4.5 and RCP6.0: Two intermediate stabilisation pathways in which radiative forcing is stabilised at approximately 4.5 W m-2 and 6.0 W m-2 after 2100 (the corresponding ECPs assuming constant concentrations after 2150); RCP8.5: One high pathway for which radiative forcing reaches greater than 8.5 W m-2 by 2100 and continues to rise for some amount of time (the corresponding ECP assuming constant emissions after 2100 and constant concentrations after 2250). More on RCPs.
| Reanalyses || Reanalyses are estimates of historical atmospheric, hydrographic or other climate relevant quantities, created by processing past climate data using fixed state-of-the-art weather forecasting or ocean circulation models with data assimilation techniques. |
| Seasonal forecasts || ? |