“…Since GVA growth rate is stationary and temperature fluctuations in levels are nonstationary, studying the relationship between GVA growth and weather variables would reintroduce trends in the specification (for a deeper discussion, see Newell et al (2021) and Tol (2019)). For this reason, I consider first-differenced, stationary weather variables, whereby I first compute any non-linear function and then take the first difference, following a more recent approach (Akyapi et al, 2022;Kahn et al, 2021;Kotz et al, 2021;Letta & Tol, 2019;Newell et al, 2021) rather than using levels in weather variables (Acevedo 13 ©International Monetary Fund. Not for Redistribution Burke et al, 2015;Dell et al, 2012;Henseler & Schumacher, 2019).…”