Natural Hazards and Earth System Sciences 

Here approaches to rank precipitation events according to their hazard characteristics are presented, while their impacts depend on many other factors as well like the orography, hydrological situation, exposure and vulnerability. Determining the severity of a precipitation event is not straight forward, as it depends on both the intensity on different time scales and the spatial extent. The weather extremity index (WEI) and the cross-scale WEI (xWEI) are used to determine the extremeness of precipitation events. The devastating event in the Ahr valley in Germany in July 2021 is shown to rank No 1 or 4 for Germany, dependent on the measure used. This emphasizes that it was extreme across multiple spatial and temporal scales, and the importance of considering different scales to determine the extremeness of rainfall events.

The NHESS paper “A climate-conditioned catastrophe risk model for UK flooding” by Bates and colleagues presents and validates a new flood model for the UK that simulates pluvial, fluvial and coastal flood risks at a resolution of 20 to 25 metres. The authors then use their scheme to estimate the probability-loss distribution for UK flooding under various future climate and policy scenarios. Their paper provides the most detailed and realistic analysis to date of current and future flood risk in the UK. The key findings of their work are: (1) Previous UK flood losses based on government data and used in national climate change risk assessments are overestimated by a factor of about 3. (2) Official UK estimates lie well outside the paper's modelled loss distribution, which is plausibly centred on the observations. (3) The UK 1% annual probability flood losses were only about 6% greater in the average climate conditions of 2020 than for the period of historical river flow and rainfall observations (centred approximately on 1995). (4) Increases in risk can be kept to around ~8% if all COP26 2030 carbon emission reduction pledges and ‘net zero’ commitments are implemented in full. (5) Implementing only the COP26 pledges increases UK 1% annual probability flood losses by ~23% above recent historical values, and potentially ~37% if climate sensitivity turns out to be higher than currently thought.

This paper examines the warning deficits in conjunction with the major flooding event in Germany of summer 2021. The event caused many fatalities and enormous damage. The warning procedures proved to be insufficient, and after investigations it was decided to install a cell broadcast system in Germany, which is already in place today. The deeper investigations on the warning perceptions and the influencing factors is of major interest to readers beyond the scientific community.

I agree with the statement proposed

The topic treated in this work is potentially interesting for our community, giving the threats presented for Sub-Saharan Africa; it is also a review, so it has the capability to attract a lot of attention from the public.