The long-term temperature record from Markree Observatory, County Sligo, from 1842 to 2011

Abstract

This study analysed long-term temperature patterns in the north-west of Ireland using a previously unexplored data-set from Markree Observatory, County Sligo. The Markree series extends back to 1842, making it one of the longest instrumental temperature records in Ireland and is renowned for holding the lowest recorded temperature for the island of Ireland, 198C on 16 January 1881. Despite its length, this record has been largely absent from past analyses of Ireland’s long-term temperature trends, rendering spatial coverage for the extended Irish climate chronology incomplete. Daily data stored in a variety of
the historical archives were gathered and digitised and monthly records created. Calibrations to account for instrumentation, time of reading and exposure were applied where possible in order to standardise the record. Trends were subsequently investigated for seasonal averages of daily minimum, maximum and mean temperatures, and a comparison with previously published long Irish temperature records was carried out to situate the Markree record among the existing long-term series. Although the Markree series follows similar patterns to the other long-term temperature records, it displays more decadal variability,
particularly in its minimum values which show a higher rate of late twentiethcentury warming compared to the other records. Due to its geographic location and surrounding topography shielding the site from direct ocean influences and prevailing south-westerly winds, Markree displays characteristic features of a more inland station (low minimum temperatures and large diurnal ranges) even though it is located only 7 km from the Atlantic Ocean. Such findings highlight the necessity of including the Markree data-set in future Irish climate change research.