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Abstract Global warming is expected to exacerbate heat stress. Additionally, biogeophysical effects of land cover and land management changes (LCLMC) could substantially alter temperature and relative humidity locally and non‐locally. Thereby, LCLMC could affect the occupational capacity to safely perform physical work under hot environments (labor capacity). However, these effects have never been quantified globally using a multi‐model setup. Building on results from stylized sensitivity experiments of (a) cropland expansion, (b) irrigation expansion, and (c) afforestation conducted by three fully coupled Earth System Models (ESMs), we assess the local as well as non‐local effects on heat stress and labor capacity. We found that LCLMC leads to substantial changes in temperature; however, the concomitant changes in humidity could largely diminish the combined impact on moist heat. Moreover, cropland expansion and afforestation cause inconsistent responses of day‐ and night‐time temperature, which has strong implications for labor capacity. Across the ESMs, the results are mixed in terms of sign and magnitude. Overall, LCLMC result in non‐negligible impacts on heat stress and labor capacity in low‐latitude regions during the warmest seasons. In some locations, the changes of monthly average labor capacity, which are induced by the local effects of individual LCLMC options, could reach −14 and +15 percentage points. Thus, LCLMC‐induced impacts on heat stress and their consequences for adaptation should be accounted for when designing LCLMC‐related policies to ensure sustainable development.

Abstract To monitor the success of carbon dioxide removal (CDR) or solar radiation management (SRM) that offset anthropogenic climate change, the forced response to any external forcing is required to be detectable against internal variability. Thus far, only the detectability of SRM has been examined using both a stationary and nonstationary detection and attribution method. Here, the spatiotemporal detectability of the forced response to artificial ocean alkalinization (AOA) and stratospheric aerosol injection (SAI) as exemplary methods for CDR and SRM, respectively, is compared in Max Planck Institute Earth System Model (MPI‐ESM) experiments using regularized optimal fingerprinting and single‐model estimates of internal variability, while working under a stationary or nonstationary null hypothesis. Although both experiments are forced by emissions according to the Representative Concentration Pathway 8.5 (RCP8.5) and target the climate of the RCP4.5 scenario using AOA or SAI, detection timescales reflect the fundamentally different forcing agents. Moreover, detectability timescales are sensitive to the choice of null hypothesis. Globally, changes in the CO2 system in seawater are detected earlier than the response in temperature to AOA but later in the case of SAI. Locally, the detection time scales depend on the physical, chemical, and radiative impacts of CDR and SRM forcing on the climate system, as well as patterns of internal variability, which is highlighted for oceanic heat and carbon storage.