5 reasons we know extreme weather events are increasing

2002, 2003, 2006, 2007, 2010 

Those are the 5 hottest summers in European history between 1500 and 2010. 

The 5 coldest summers in European history? 1695, 1821, 1888, 1902, 1923

See the trend? 

European summer temperatures for 1500–2010. Vertical lines show the temperature deviations from average of individual summers, the five coldest and the five warmest are highlighted. The grey histogram shows the distribution for the 1500–2002 period with a Gaussian fit shown in black. That 2010, 2003, 2002, 2006 and 2007 are the warmest summers on record is clearly not just random but a systematic result of a warming climate. 

The European heat wave of 2003 may not have destroyed any buildings – but it is well documented that it caused about 70,000 fatalities. This is the type of event for which the probability has increased by a factor of five due to global warming – and is likely to rise to a factor twelve over the next thirty years. 

In a 2011 paper published in the Proceedings of the National Academy, the authors calculated the expected number of monthly heat records based the observed gradual changes in climate. The paper determined that we should experience five times the number of heat records with 1 degree of warming versus the number expected in a stationary climate. This is exactly what we are seeing. 

I calculated the probability that the 5 hottest summers in 510 years all came from the last decade. The odds would be less than 1 in a billion if we were in a stable climate! 

I've been thinking a lot about what standards we should use for designing resilient buildings that are capable of handling these types of extreme weather events. 

This paper would suggest that our building design decisions may actually save lives. If heat waves, like the European heat wave of 2003 that killed 70,000 people, are going to be 12x more likely over the next 30 years – how should we design our buildings so they are able to maintain healthy temperatures at affordable costs when the extreme heat waves hit here at home? 

[Real Climate]