Once again tornadoes and other extreme events are in the news. Here, for perspective, are US and global trends in deaths and death rates from such events from 1900-2006.
For tornadoes, since peaking in the early decades of the 20th century, deaths declined by over 80% while death rates declined by 92% (based on 10-year moving averages for 1916-2006) . [See Figures 6 and 7.]
For other extreme events – lightning, floods and hurricanes – US deaths and death rates are also below their peak levels of a few decades ago. Their declines in annual mortality range from 62 to 80%, while mortality rates declined 75 to 95%.
Globally, mortality and mortality rates have declined by 95% or more since the 1920s. The largest improvements came from declines in mortality due to droughts and floods, which apparently were responsible for 93% of all deaths caused by extreme events during the 20th Century. For windstorms, which, at 6%, contributed most of the remaining fatalities, mortality rates are also lower today but there are no clear trends for mortality.
So contrary to what some may expect from global warming, matters are not getting worse. This is mainly due to adaptation.
Also, the linked paper (above), tells us that on average, extreme cold kills many more people directly than does extreme heat.