An updated assessment of past and future warming over France based on a regional observational constraint

Abstract

Abstract. Building on CMIP6 climate simulations, updated global and regional observations, and recently introduced statistical methods, we provide an updated assessment of past and future warming over France. Following the IPCC AR6 and recent global-scale studies, we combine model results with observations to constrain climate change at the regional scale. Over mainland France, the forced warming in 2020 with respect to 1900–1930 is assessed to be 1.66 [1.41 to 1.90] ∘C, i.e., in the upper range of the CMIP6 estimates, and is almost entirely human-induced. A refined view of the seasonality of this past warming is provided through updated daily climate normals. Projected warming in response to an intermediate emission scenario is assessed to be 3.8 ∘C (2.9 to 4.8 ∘C) in 2100 and rises up to 6.7 [5.2 to 8.2] ∘C in a very high emission scenario, i.e., substantially higher than in previous ensembles of global and regional simulations. Winter warming and summer warming are expected to be about 15 % lower than and 30 % higher than the annual mean warming, respectively, for all scenarios and time periods. This work highlights the importance of combining various lines of evidence, including model and observed data, to deliver the most reliable climate information. This refined regional assessment can feed adaptation planning for a range of activities and provides additional rationale for urgent climate action. Code is made available to facilitate replication over other areas or political entities.

Emergent Constrained Projections of Mean and Extreme Warming in China

“…Local projected warming is driven by GSAT warming, and applying regional constraints can improve the reliability of constrained projections (Qasmi & Ribes, 2022; Ribes et al., 2022). To account for the local warming related to the local feedback, we further correct the local projected warming by using the local residual warming trend (Text S4 in Supporting Information ).…”

“…The constrained GSAT warming is useful for other climate quantities that scale well with GSAT change (Hu et al., 2021; Lee et al., 2021). The projections of local temperature and water availability over the Artic and Eurasian continents can be constrained by using the observed GSAT warming trend (Chai et al., 2022; Hu et al., 2021; Ribes et al., 2022). In addition, combining the observed evidence of global and regional warming can refine the regional projection assessment (Qasmi & Ribes, 2022; Ribes et al., 2022).…”

“…The projections of local temperature and water availability over the Artic and Eurasian continents can be constrained by using the observed GSAT warming trend (Chai et al., 2022; Hu et al., 2021; Ribes et al., 2022). In addition, combining the observed evidence of global and regional warming can refine the regional projection assessment (Qasmi & Ribes, 2022; Ribes et al., 2022). In this study, we aim to constrain the mean and extreme temperature projections over China by using reliable observational data sets.…”

Summer Deep Depressions Increase Over the Eastern North Atlantic

“…Climate has been warming quickly in Western Europe. Over mainland France, for instance, mean daily temperatures estimated over the 1950–2022 period, show an increase of more than 1.5°C as a response to climate change (Ribes et al., 2022), and mean daily maximum temperatures in the region have been measured to increase twice to three time as much as the global mean (Vautard et al., 2023). More notably, heatwaves are increasing, as illustrated by several unprecedented events in the last 20 years, with a number of observed record‐breaking temperatures exceeding those expected in a stationary climate (Bador et al., 2016).…”

“…More notably, heatwaves are increasing, as illustrated by several unprecedented events in the last 20 years, with a number of observed record‐breaking temperatures exceeding those expected in a stationary climate (Bador et al., 2016). While climate projections show an increase of extreme temperatures in Western Europe with climate change, the amplitude is only captured by very few current climate simulations (Boé et al., 2020; Ribes et al., 2022; van Oldenborgh et al., 2009, 2022).…”