Reassessing Ireland’s maximum air temperature record value and the monthly maximum air temperature records for June, July and August

It is essential to have validated and trusted records of past climate extremes.

These records are used by planners and policymakers to help them make informed decisions regarding many different sectors - from construction projects to health budgets, from environmental legislation to infrastructure planning, for example.

They are also used to tune and improve climate models, leading to more reliable future projections in a changing climate. Assessing and improving on the abilities of climate models to reproduce these (by definition) rare events, provides a stronger basis from which better informed mitigation and adaptation measures against such potential future climate extremes can be taken.

In this research, we present the comprehensive re-evaluation process of the Irish national maximum air temperature and the records for the months of June, July and August.

For records prior to 1961, we use newly digitised historical climate data from the Met Éireann archives and integrate advanced 20CRv3 sparse-input reanalysis data, station metadata, historical newspaper articles, and contemporaneous references from the examined timeframes. For more recent records, we use climate data from the Met Éireann database and integrate the most recent ECMWF reanalyses products, along with all relevant metadata for our analysis. We also employ time series methods and extreme value theory to help us assess the veracity of the records.

The result of this study will be a list of validated maximum air temperature summer monthly records for Ireland. This process will then be applied to other months and other climate variables in future work.

This research underscores the significance of data rescue efforts in advancing our understanding of past climate extremes, and advocates for continued digitisation and analysis of historical climate data and metadata. By refining national air temperature records through the integration of historical data and advanced reanalysis techniques, the research contributes to a more comprehensive understanding of climate dynamics.