Over the past month we have discussed and illustrated how hurricane risk is changing in a series of LinkedIn posts. This blog is designed to summarize our findings, with additional analysis. Here are the main points covered:
- Today’s hurricane risk is not the past
- We now live in a world that is (at least) 1.2C warmer than pre-industrial levels. As a result, we are reaching unprecedented temperatures across our oceans, including the North Atlantic.
- Warmer oceans mean more favourable conditions for hurricane intensification.
- This means that today’s hurricane risk (i.e. in a 1.2C+ world) is already very different to 10-20 years ago.
- What comes next?
- The warming trend is accelerating, with 1.5C – 2C worlds projected to occur before 2050 under most scenarios.
- This means oceans will warm even further, and coastal regions until now sheltered from hurricane risk thanks to cooler waters, will face increasing levels of threats.
- This is particularly worrying for the East coast of the US, and more generally at higher latitudes.
- What can be done?
- Reask TC risk data is designed to reflect changes in the climate.
- Reask data can be used to climate-adjust existing views and risk modelling framework.
In the figure above we track and project the number of expected US hurricane landfalls as our world warms. In the past couple of seasons, we have reached the 1.2C level (see red arrow), with 2023 now reported to reach 1.25C. This means our world is already 0.5C warmer than it was around year 2000, with half that warming occurring since 2015. The trend is accelerating.
Now, as our world warms, so do our oceans, and as a result hurricanes find it easier to intensify. According to Reask modelling this means the expected number of annual US hurricane landfalls has already increased by 12-13 % since the early 2000s.
-> Our question for risk practitioners across the insurance and finance industry is: are you pricing for this?
But there is more, and the figure above is only the tip of the iceberg – what happens for more severe events?
Well the picture gets much worse. With ocean temperatures getting more favourable along the US coast, major hurricanes (category 3 and above) are becoming increasingly more likely. The animation below shows how the likelihood of a major hurricane hit changes with different levels of warming. We have computed the change factors using 1C as a baseline (i.e. circa 2015).
-> As ocean temperatures to the North become more favourable (e.g. reaching 26C), most of the US East coast sees its risk of major hurricane hit triple from 2015 levels under 2C+ warming.
The increased shift in risk from hurricane to major hurricane levels is very worrying, especially because it is strongly backed by our physical understanding of how hurricanes behave. While some debate still exists as to whether we are likely to see more or less events in a warmer world (see here for instance), the consensus for those events getting stronger is a lot clearer:
-> warmer oceans mean more likely intensification leading to more severe events.
Unfortunately, it is that second point that completely dominates US east coast risk. The return period curve below shows the result from a sensitivity test of our TC modelling system, where we first assume hurricane frequency remains unchanged (orange solid line), and then repeat the exercise letting it increase according to our models (red dashed line). Our conclusion here is that TC frequency basically does not matter – both lines almost merge in the tail, where severe damage occurs. When looking at return period levels associated with severe events we find a similar conclusion as above, regardless of the frequency assumption used:
-> Rare severe events of today could be 3 times more common under a 2 C warming
Where to from here?
This week we are hosting a series of webinars on the topic above, and will showcase how our data can be implemented to help adjust your current view of risk now, and in the future. Please get in touch with us at firstname.lastname@example.org if you’d like a recording of that webinar, or if you want to discuss any of the above with our team.