There are no standards in terms of a definite guidebook for now. Certainly the official projections from the IPCC are what we use for, first of all, sea level rise. Depending on the emissions scenarios, you get different rates of sea level rise anywhere from today to into the next century.
We use that for flood and inundation levels. We also use that as input conditions for wave modelling, for example. When we look at wave forces, the amount of wave energy that hits the structure will depend on the water depth. You can imagine that as sea levels are rising that will allow bigger waves to come closer to shore. We do use that.
The more tricky thing is about developing.... I was mentioning these changes in storm intensity. There is no clear consensus yet as to what to use in terms of increasing hurricane intensity and/or frequency. It's an area of evolving science. In terms of storm surge statistics, we use the past because that's what we have.
I mentioned that the calculations have to be updated. With Fiona, the data point now lies outside the range of what has been historically observed. All of a sudden, your extreme one per cent probability storm gets higher because hurricane Fiona is now part of the statistics.
It's an evolving practice.