The potential effect of climate change on our business future is discussed in our adaptation reports. Our first adaptation report, published in 2011, explains to government how we are preparing for a changing climate and sets out how we intend to manage material risks associated with climate change and outlines our partnership-based approach. Our second adaptation report, published in 2015, builds on this and reports progress on our actions.
Our third adaptation report is our latest update on climate change resilience, setting out our key messages and detailing our refreshed risk assessment. By assessing over 100 climate-related risks and engaging with over 1000 stakeholders, we present our most detailed progress update on climate change adaptation.
We have first-hand experience of the impacts of extreme weather events on our operations and customers. During 2018, 2020 and 2021 we have experienced extremely hot, dry weather coupled with significantly increased demand for water over the summer, while also experiencing more significant wet weather. In 2020 and 2021, three storm events contributed to a notable increase in the number of sewer flooding incidents, with 40 per cent of incidents occurring on just six days of stormy weather during the period. There is a degree of uncertainty in the longer term because of outcomes from different emissions scenarios and the complexity of climate modelling, but is agreed that experiences like this will become more common and need to be planned for.
As a first step to incorporate longer-term climate change impacts more explicitly in our corporate risk framework in Spring 2021, we screened all of our corporate risks for their vulnerability to climate change. This was a broadly qualitative analysis though it used projected changes for North West England at a global mean warming of 2°C and 4°C above pre-industrial levels from the UKCP18 Derived Projections of Future Climate over the UK, Met office. We have since benchmarked over 100 climate-sensitive risks to identify areas requiring further investigation.
The next step is to consider our corporate strategy, risks and opportunities under three climate change scenarios at 2050 and 2100. This is part of our company-wide multi-factor scenario analysis and strategic planning. This activity further raises the profile of climate change adaptation and allows the board enhanced insight into climate risks from within existing risk management processes. It will highlight where climate risks are not well understood or where existing controls are deemed inadequate to manage the risk in the long-term to allow corrective action to be taken.