Ireland's State of the Environment Report 2024

83 Chapter 4: Climate Change 2. Climate change is happening Observed impacts Observations clearly show that Ireland’s climate is changing. Monitoring records show increases in average temperature, changes in precipitation patterns, sea level rise and weather extremes. The most immediate risks to Ireland from climate change are predominantly those associated with changes in extremes, such as floods, droughts and storms. In line with global trends, Ireland’s annual average temperature has increased by approximately 1°C over the last 100 years, with 16 of the 20 warmest years occurring since 1990, and 2023 being the hottest year on record. Extremes of heat in Ireland (heatwaves) are becoming more frequent and more severe, while extremes of cold (cold waves) are becoming less frequent and less severe. Heatwaves, such as the 2022 heatwave, where temperatures reached 33°C (at Phoenix Park), have been made more likely by climate change. Heavy rainfall events have been 7% more intense over the last 30 years than over the previous 30 years, with evidence linking these events to climate change (Figure 4.2). While there is evidence that average river flows increased across the country between 1972 and 2017, there is also evidence of an increase in recent years in the frequency and intensity of potential drought conditions, especially in the east of Ireland. Satellite observations indicate that the sea level around Ireland has risen by approximately 2-3 mm a year since the early 1990s, with higher rates of increase observed in Dublin and Cork. Both sea surface temperatures and ocean heat content have increased in Ireland’s territorial waters, consistent with globally observed changes. In Irish waters, there have been changes in marine ecosystems, including changes in the seasonality and abundance of many species. The main impacts of climate change on Irish species and habitats observed to date have been changes in species abundance and distribution, phenology, community composition, habitat structure and ecosystem processes. Ireland’s network of monitoring stations is part of a global observing system (Topic Box 4.2). Figure 4.2  Midleton flooding, October 2023 Topic Box 4.2  Global observation networks The Global Climate Observing System National Committee works to ensure the sustained provision of reliable physical, chemical and biological observations and data records for the total climate system – across the atmospheric, oceanic and terrestrial domains, including hydrological and carbon cycles – for Ireland. The committee is chaired by Met Éireann and has representatives from the Marine Institute and the EPA, with additional support provided by Teagasc, as well as remote-sensing and other experts. Ireland joined the Integrated Carbon Observation System in January 2023. The Integrated Carbon Observation System provides standardised and open data from more than 170 measurement stations across 16 European countries. The stations observe greenhouse gas concentrations in the atmosphere as well as carbon fluxes between the atmosphere, the land surface and the oceans. Ireland has a network of ten monitoring sites that measure greenhouse gases in grasslands, peatlands, forests, coastal areas and in the North Atlantic. Among the stations are four atmosphere stations, five ecosystem stations and two ocean stations.