Shifting summer holidays in Spain as an adaptation measure to climate change

This paper assesses whether moving summer holidays to the warmest period of the year in Spain could be a useful climate change adaptation strategy. While the most popular period for Spanish summer holidays has traditionally been August, we illustrate that the second half of July is the hottest period of the year and when the negative effects of high temperatures are most pronounced. If the holiday period in the second fortnight of August was moved to the second fortnight of July, some of the associated impacts would be mitigated due to the reduced anthropogenic activity during non-working days. In particular, we find a significant reduction in the annual peak of labour productivity loss (~25 %) and, to a lesser extent, of electricity demand and near-surface ozone concentrations (~3-4 %). Finally, we also show that global warming could lead to enhanced differences between both fortnights (even with no change in the seasonal cycle of temperature) because of the non-linear relationships between temperature and its impacts. Therefore, the positive effect of shifting holidays would be even larger in the coming future.We acknowledge support from MALONE (PID2021-122252OB-I00), project funded by the Spanish Ministry of Science and Innovation. This research work has also received support from the European Commission – NextGenerationEU (Regulation EU 2020/2094), through CSIC's Interdisciplinary Thematic Platform Clima (PTI Clima)/Development of Operational Climate Services. We thank the Spanish Instituto Nacional de Estadística (INE) and Red Eléctrica de España (REE) for providing the trips by residents and electricity demand data, respectively. The authors are also grateful to the World Climate Research Programme's Working Group on Coupled Modelling, which is responsible for CMIP, and the modelling groups for producing and making available their model outputs. ERA5 and CAMS data provided courtesy ECMWF. The authors thank two anonymous reviewers for their useful comments.Peer reviewe