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Answers to some frequently asked questions.

  • General Queries

    Here are answers to some frequently asked questions about the Climate Ireland Climate Change Projection Map viewers. Please contact if you have other questions.

  • Data Dictionary part 1

    • Maximum temperature: average maximum temperature during period of interest (annual or seasonal).
    • Minimum temperature: average minimum temperature during period of interest (annual or seasonal).
    • Mean temperature: average mean temperature during period of interest (annual or seasonal).
    • Precipitation: projection of average levels of precipitation.
    • Driving rain: projected change (%) in the driving rain metric.
    • Evapotranspiration: projected change (%) in evapotranspiration.
    • Frost days: number of days when minimum temperatures are <0°C.
    • Growing season length: length of the growing season defined as the number of days between the first occurrence of at least 6 consecutive days with a daily mean temperature > 5°C and the first occurrence of at least 6 consecutive days with a daily mean temperature < 5°C.
    • Growing season start: start of the growing season (number of days early).
    • Heating degree days: number of days where average temperature is below 15.5 °C (i.e.: a temperature below which heating is required).
    • Icing days: number of days when maximum temperatures are <0°C.
    • Night >15 degrees (summer nights): number of nights when minimum temperatures are >15°C.

  • Data Dictionary part 2

    • No. of heatwaves: number of heatwave events. Heat wave events are defined as periods of at least three consecutive days where maximum temperatures exceed >95% of the normal monthly distribution.
    • R20mm (wet days): number of days with rainfall >20mm.
    • R30mm (very wet days): number of days with rainfall >30mm.
    • RR1 (no. of wet days): number of days with daily precipitation amount ≥1 mm.
    • Rx1 day:  maximum daily precipitation during the period of interest (annual or seasonal).
    • Rx5 day: five day maximum precipitation during the period of interest (annual or seasonal).
    • Snowfall: projection of snowfall.
    • Solar photovoltaic: projected change (%) in solar PV power.
    • Summer days: number of days with maximum temperature >25°C.
    • TNn: minimum value of daily minimum temperature (TN) during period of interest (annual or seasonal).
    • TNx: maximum value of daily minimum temperature during period of interest (annual or seasonal).
    • TXn: minimum value of daily maximum temperature (TX) during period of interest (annual or seasonal).
    • TXx: maximum value of daily maximum temperature (TX) during period of interest (annual or seasonal).
    • Wind energy: projected change (%) in wind energy resource at 120m elevation.
    • Wind speed: projected change (%) in windspeed at 10m elevation.

  • What is this map viewer for?

    The map viewers are intended as a resource of standardised climate projections for use in planning for a changed climate in the future. It is aimed at practitioners, climate stakeholders, researchers, technicians and decision makers. The viewers aim to support the needs and requirements of the Irish adaptation and planning community. 

  • Is a climate projection a prediction?

    Climate projections are simulations of Earth's climate for future decades (2071-2100, for example) or for specific warming levels/thresholds (2.5oC for example). These are not predictions for a day, month, year or decade. Instead, they are the average projection of a representative year for a period of time, here 20 or 30 year periods.

  • What is TRANSLATE?

    The TRANSLATE project is a Met Éireann lead initiative with the project team comprising of climate researchers from Irish Centre for High End Computing (ICHEC) - NUI Galway, University College Cork (UCC) - SFI Research Centre for Energy, Climate and Marine (MaREI). It aimed to standardise future climate projections for Ireland and develop climate services that meet the climate information needs of decision makers.

    TRANSLATE provides standardised and bias-corrected national climate projections to the end of the 21st century for Ireland. The bias correction means that for the first-time, users can view the possible values for temperature and precipitation variables in the future, in addition to the relative change. 

    TRANSLATE is novel in its delivery of Global Warming Level (GWL) projections. This allows practitioners and users to view how Ireland’s climate could change as global temperatures increase to 1.5°C, 2°C, 2.5°C, 3°C or 4°C.

    TRANSLATE also has a climate services section, to find out more about it, contact

    Climate services, provided by Met Éireann, are focused on the timely production and provision of high-quality data (observational data, gridded data, scientific analysis, etc.) and products to decision makers to support Irish society at large and facilitate the development and evaluation of climate adaptation and mitigation strategies for Ireland.

  • What are the main findings from TRANSLATE?

    TRANSLATE projections consistently show an increase in temperature across Ireland, with increased warming with greater global warming. Heat extremes are projected to become more frequent and more intense, while the opposite is expected for cold extremes. Changes in rainfall are more uncertain, although extreme rainfall events and dry periods are expected to become more frequent.

  • Where can I find further information about TRANSLATE?
  • What time-period and baseline are the projections based on?

    All TRANSLATE indices are measured relative to the reference period 1976-2005, which was chosen to correspond with the last 30 years of the CMIP5 historical period.

    The non-standardised indices are measured as projected percentage change (%) relative to 1981-2000. As TRANSLATE expands many of these indices will be replaced with updated, standardised datasets and maps.

  • What is the spatial and temporal resolution?

    1. All the projected maps have a spatial resolution equal to 1.5 x 1.5 km.
    2. The standardised and bias-corrected set of TRANSLATE data files have daily resolution over a full annual cycle and the projections have different temporal resolution, annually and/or seasonally, with time-periods 2021-2050, 2041-2070 & 2071-2100, along with 2041-2060 for the non-standardised projections.
    3. The Coordinate Reference System is EPSG:4326 - WGS 84 (Units: Geographic).

  • What format is the data in?

    The TRANSLATE standardised and the non-standardised climate projections are available in the following formats.

    1. a set of maps disseminated through the Climate Ireland portal.
    2. a set of NetCDF data files available for download
    3. GIS compatible format for use in GIS systems

    For any other queries on data formats, contact

  • What is the "representative year"?

    TRANSLATE’s projections covers three different future time periods – 2021-2050, 2041-2070, 2071-2100. Each of these time periods cover a time span of 30 years. Rather than viewing this data as a full 30-year time series in each instance, TRANSLATE incorporates the entire 30-year time-period in one representative year. The representative year is calculated by creating a day of year average for the 30-year time series. This is done by getting the average of each day of the year, across all the models, leaving you with 365 days - a representative year. This would give you an average representation of the climate in the 30-year period. However, the variability throughout the data is captured through the pre-calculated histogram and indices files such as max temperature and in the frequency distribution files.

    The non-standardised Nolan & Flanagan projections cover the 20-year period of 2041-2060, rather than a 30-year period. They also incorporate these projections into a representative year.

  • What is a baseline?

    A baseline period is needed to define the observed climate with which climate change information is usually combined to create a climate scenario. When using climate model results for scenario construction, the baseline also serves as the reference period from which the modelled future change in climate is calculated.

    Here a 30-year baseline period has been used (1976-2005) for the standardised, bias-corrected projections, with a 20-year period (1981-2000) still in play for the non-standardised projections.

  • What are RCPs (Representative Concentration Pathways)?

    Representative Concentration Pathways, known as RCPs, are used to simulate future emissions. Each RCP represents a different amount of Greenhouse Gas emitted into the atmosphere. RCP 2.6 is the RCP that represents the least amount (low emissions/early action) of GHG emissions, RCP 4.5 is the low-middle amount (low-medium emissions/mid-action), RCP 6.0 is the high-middle amount (high-medium emissions/mid-action) and RCP 8.5 is the highest amount (high emissions/late action). These pathways are used to simulate future climate based on the amount of GHGs we produce and emit into the atmosphere.

  • What is a warming level?

    The warming levels or temperature thresholds are are defined as when the global average temperature rises X°C above pre-industrial levels (1850 -1900). The are irrespective of the year that this occurs in and are, instead, a projection of what the climate is likely to be at 2.5oC or 4oC of warming.

  • What are SSPs (Shared Socioeconomic Pathways) and does TRANSLATE use them?

    Shared Socioeconomic Pathways, also known as SSPs, are scenarios of projected socioeconomic global changes up to 2100. They focus on the socioeconomic factors that lead to anthropogenic emissions and modelling how these could change over the coming century.

    TRANLSATE utilises the CMIP5 data and RCPs to calculate the most robust dataset available for Ireland. The next iteration of TRANSLATE will incorporate the CMIP6 data and SSPs as they become available.

  • How does TRANSLATE deal with uncertainties and extremes?

    TRANSLATE’s projections are the product of the multi-model ensemble using the EPA’s “Updated High-Resolution Climate Projections for Ireland” project co-funded by Met Éireann and the Marine Institute and the EURO-CORDEX projections. Future forcing uncertainty is represented by 3 different emission scenarios (RCP 2.6, 4.5, 8.5). The TRANSLATE data is presented as an average value across all the models. It also captures the range (or spread) among each scenario to better visualise the uncertainty that arises when using climate projections.

    The range is captured by using the 10th (90% chance of being greater than this value) and 90th (10% chance of being greater than this value) percentile values across the models. This represents the upper and lower limits of the ensemble. This allows you to see the variability across the scenario.

  • Who can use the data?

    All data presented in the climate change projection map viewers and the TRANSLATE data is freely available to use. It is aimed however at technicians, researchers, practitioners, climate stakeholders and decision makers. The data aims to support the needs and requirements of the Irish adaptation and planning community. 

  • I am interested in a particular Climate Service: Can anyone help me with that?

    Yes, contact to discuss your requirements.

  • How would I cite this data?

    O’Brien, E. and Nolan, P., 2023. TRANSLATE: standardized climate projections for Ireland. Frontiers in Climate, 5, p.1166828.

    Nolan, P. and Flanagan, J., 2021. Research 339: High-resolution climate projections for Ireland. A multi-model ensemble approach. (for all 2041-2060 datasets)

    See for more details.