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The evolution of near‐surface air temperature is influenced by various dynamical, radiative, and surface‐atmosphere exchange processes whose contributions are still not completely quantified. Applying stepwise multiple linear regression to Coupled Model Intercomparison Project phase 5 (CMIP5) model simulations and focusing on radiation (diagnosed by incoming shortwave and incoming longwave radiation) and land surface conditions (diagnosed by soil moisture and albedo) about 79% of the interannual variability and 99% of the multidecadal trend of monthly mean daily maximum temperature over land can be explained. The linear model captures well the temperature variability in middle‐to‐high latitudes and in regions close to the equator, whereas its explanatory potential is limited in deserts. While radiation is an essential explanatory variable over almost all of the analyzed domain, land surface conditions show a pronounced relation to temperature in some confined regions. These findings highlight that considering local‐to‐regional processes is crucial for correctly assessing interannual temperature variability and future temperature trends. The evolution of near‐surface air temperature is mostly impacted by radiation, heat advection, and land‐atmosphere interactions. In this study, we quantify the impact of incoming shortwave and longwave radiation as well as soil moisture and albedo on year‐to‐year variability and long‐term trends of average daily maximum temperature. Applying a linear regression model to the output of climate models, about 80% of the year‐to‐year temperature variability and 99% of the long‐term temperature trend can be explained by the four considered radiation and land surface variables. The radiation components are essential for explaining the temperature evolution almost everywhere. Soil moisture and albedo impact temperature in some confined regions. Incoming longwave radiation contributes strongly to year‐to‐year variability in high latitudes and explains most of the long‐term temperature trend. Incoming shortwave radiation is important in the tropics and in middle‐to‐high latitude during winter. Albedo is of special importance in regions that experience varying snow cover in different years or snow cover changes with climate change. The impact of soil moisture is highest in regions, where it limits the amount of evapotranspiration. The results highlight the fact that local‐to‐regional processes are relevant both for year‐to‐year temperature variability and future temperature trends. The used linear regression model explains about 79% of interannual temperature variability and 99% of multidecadal temperature trendRadiation explains on average about 75% to 85% of the total explained variance, while land surface conditions contribute about 15% to 25%Radiation is essential for explaining temperature variability almost everywhere, land surface conditions in some confined regions

Greenhouse gas emissions urgently need to be reduced. Even with a step up in mitigation, the goal of limiting global temperature rise to well below 2 °C remains challenging. Consequences of missing these goals are substantial, especially on regional scales. Because progress in the reduction of carbon dioxide emissions has been slow, climate engineering schemes are increasingly being discussed. But global schemes remain controversial and have important shortcomings. A reduction of global mean temperature through global-scale management of solar radiation could lead to strong regional disparities and affect rainfall patterns. On the other hand, active management of land radiative effects on a regional scale represents an alternative option of climate engineering that has been little discussed. Regional land radiative management could help to counteract warming, in particular hot extremes in densely populated and important agricultural regions. Regional land radiative management also raises some ethical issues, and its efficacy would be limited in time and space, depending on crop growing periods and constraints on agricultural management. But through its more regional focus and reliance on tested techniques, regional land radiative management avoids some of the main shortcomings associated with global radiation management. We argue that albedo-related climate benefits of land management should be considered more prominently when assessing regional-scale climate adaptation and mitigation as well as ecosystem services. Land management with the aim of reducing incoming solar radiation could help with regional-scale climate adaptation and mitigation as well as ecosystem services, and avoids several shortcomings of global geoengineering.

The mega heatwaves that struck western Europe in 2003 (ref. ) and Russia in 2010 (ref. ) are thought to provide a foretaste of future European summer climate. Our ability to anticipate such events remains poor, limiting adequate society adaptation. A deficit of precipitation in the preceding months favours summer heatwaves, but the potential predictability from spring surface-moisture deficits, addressed in only a few case studies, largely remains to be investigated. By analysing 64 years of observed temperature and precipitation we show that rainy winter/spring seasons over southern Europe inhibit hot summer days whereas dry seasons are followed by either a high or a low frequency of hot days, generalizing findings obtained over southeastern Europe. Observations indicate that summer heat is more sensitive to the occurrence of specific weather regimes in initially dry cases than wet cases, inducing this asymmetry in summer heat predictability. Then, simulations from the Coupled Model Intercomparison Project (ref.  and J-L., Dufresne, manuscript in preparation) indicate that projected drier conditions over southern Europe are likely to induce a widening in the frequency distribution of hot summer days, as the wet winter/spring seasons are likely to become rare. These mechanisms are found to play an increasingly important role in coming decades, with more hot extremes and a modified hot-day predictability.