The Emerald Isle turns white: Snow and very low surface temperatures over Ireland during Christmas 2000

• Published in: Weather
• Main Author: Graham, Edward
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2004
• Subjects: Arctic; Emerald Isle; Folland
• Online Access: https://pure.uhi.ac.uk/en/publications/09fdd85f-e9a8-412d-b33c-6230db5b896f; https://doi.org/10.1256/wea.59.03; http://onlinelibrary.wiley.com/doi/10.1256/wea.59.03/epdf

Popular mythology labels Ireland as having a mild and damp climate, with few extremes of temperature throughout the year. For the most part, this classification is justified, especially in the western half of the country where the winter climate is characterised by strong advection of heat energy from the Atlantic (Sweeney 1987/88). Occasionally, however, there are exceptions to this rule, such as in late December 2000 when a series of polar lows and troughs, embedded in a bitterly cold Arctic airstream, brought snow to much of the country. On 27 December 2000, Aldergrove Airport in Northern Ireland recorded its heaviest daily snowfall (19 cm) since records began there in 1930 (Met Office Press Release on http://www.metoffice.com/corporate/pressoffice/). Further-more, weak baroclinic gradients following the polar troughs allowed intense radiation- al cooling to take place. The result was some of the lowest temperatures on record in Ireland for the month of December, with –14.0 °C being recorded at Straide, Co. Mayo, early on the 29th. At the end of a century which has seen an unprecedented rise in global temperatures (Folland et al.2002), and even more worrying predictions for the coming one (Collins and Senior 2002), it was perhaps fitting that the last week of the cli- matic millennium should turn the tables somewhat! In this article, I present a detailed chronology of events during the cold spell. I follow with a closer in-depth analysis of the regions with the lowest temperatures using infrared satellite imagery. I conclude by placing the December 2000 cold spell in a historical context for Ireland.