An assessment of teleconnection-driven climate and solar energy variability in Ireland and the UK

This thesis focuses on the relationship between large-scale northern hemisphere atmospheric pressure patterns (North Atlantic Oscillation – NAO; East Atlantic pattern – EA; Scandinavian pattern – SCAND), and spatio-temporal variability of solar energy resources (incident SW radiation). Published work had indicated that some of these patterns exerted an impact on European solar energy resources, particularly in winter. Encouraging initial results on the relationship between the NAO’s winter index and incident short-wave (SW) solar radiation variability on the domain centered on and around the islands of Ireland and Britain led to the formulation of the main research questions for this thesis. In this thesis, insights from previous studies regarding winter solar energy resource variability in this geographical domain were greatly updated, deepened and expanded in terms of the datasets considered, geographical focus, climate drivers, spatial resolution and the time period analysed. This was followed by a similar analysis for all calendar months of the year, with particular consideration of the (boreal) summer season in the islands of Ireland and Britain. The SW radiation variability patterns in summer differ from those seen for the colder months of the year. In the winter season, the NAO-linked patterns of SW resources variability in the region change mostly zonally (west-east) and are linked to orographic features such as mountains, but in summer the main spatial patterns of NAO-linked SW variability changes along coastal to inland transects. In particular, incident SW radiation at inland locations correlates strongly with the summer NAO index, unlike at coastal stations. Furthermore, at inland locations, the summer NAO influences the pattern of intra-day temporal variability of SW radiation that expresses itself most clearly the early to late afternoon, a period of expected high PV generation. This effect was not identified at coastal sites. Lastly, this thesis concludes with an exploration of the implications of all of the above effects on likely solar PV production, based on modelled PV data that included variables other than SW radiation. This PV modelling exercise, for which various data sources were considered offered further insights into what was observed in the previous chapters. In particular, it showed that the previously identified teleconnection-driven spatio-temporal patterns of SW radiation variability carried through to modelled PV generation, especially for the NAO pattern in both summer and winter.