Climate change increased deaths in Stockholm from 1980-2009, with 300 more than there would have been without temperature increases, researchers said. A study, from Umea University researchers and published in the journal Nature Climate Change, said global warming not only means a general increase in temperature but also increases the frequency, intensity and duration of heat waves, which can cause an increase in premature deaths. Periods of extremely high temperatures increased significantly over the period 1980-2009, contributing to about 300 more deaths during heat waves than had been the case without climate change, they said. \"Mortality associated with extreme heat during the relevant period was doubled, compared to if we had not had some climate change,\" said study leader Daniel Oudin Astrom, a doctoral student in Occupational and Environmental Medicine. \"Furthermore, we saw that even though the winters have become milder, extremely cold periods occurred more often, which also contributed to a small increase in mortality during the winter.\" Despite research on the effects of climate change Swedes haven\'t changed their attitude of willingness to protect themselves against extreme temperatures, Astrom said. \"The study findings do not suggest any adaptation of the Swedes when it comes to confronting the increasingly warmer climate, such as increased use of air conditioning in elderly housing,\" he said. \"It is probably because there is relatively little knowledge in regards to increased temperatures and heat waves on health.\"