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[email protected] Reply to ‘Adaptation to extreme heat in Stockholm County, Sweden’ Oudin Åström et al. reply — We approach of comparing patterns over 30-year studies cited by Knappenberger et al., thank Knappenberger and colleagues time periods. The observed changes are the socio-economic development, epidemiological for their interest in our research1. Their result of natural processes, including regional transitions and health system changes were correspondence expresses two concerns: a climate variability, and anthropogenic and continue to be the main drivers of possible bias in the temperature data2 and influences, including urbanization3. changes in population sensitivity — not appropriate consideration of adaptation Our method of comparing the climate explicit, planned actions to prepare for to extreme-heat events over the century. during two 30-year periods is valid for climate change impacts. These changes also To clarify, we estimated the impacts of any two periods.