This colloquium will focus on two natural hazards challenges- geomagnetic super-storms and heatwaves.

Extreme space weather events or super-storms have a high impact over a wide range of systems, from power supplies, aviation, satellites and radio communications to economic and social behaviour. They are becoming increasingly important as our society relies more and more on being interconnected. Space weather is driven by the interaction of the sun’s expanding atmosphere (the solar wind) with earth’s own plasma environment. Space weather activity is modulated by the approximately 11 year solar cycle. The last solar maximum was unusually weak and the next maximum may be weak also. The question is, will we see a super-storm in the next solar cycle?

Heatwaves are one of the most impactful aspects of climate. However, heatwaves at user-relevant thresholds are by definition challenging to resolve statistically. Heatwave conditions may only occur once every several years and then there are typically only one or two heatwave events per season in a given location. User-relevant thresholds are in the tail of the observed temperature distribution so that for example the 28C building overheating threshold is around the 0.95-0.99 quantile of UK summer season daily temperatures; these temperatures are observed on only 1-5% of summer days.

In both these cases we have long-term observations going back to the 1800s. What is the nature and quality of these observations and what can we learn from them? Can we quantify the uncertainties both in the data and in the conclusions that we draw from them? Can the past be a guide to the future?

*Presenting results arising from a 2017-18 Fulbright-Lloyd’s of London Scholarship.