1. Introduction
One of the impacts expected from global climate change is an increase in the impacts of flooding.
The Ministry for the Environment (MfE) has developed guidance for local government on best practice in assessing the impact of climate change in a region. For flood risk, the first stage of this is to assess both qualitatively and quantitatively whether climate change is likely to be an issue. To achieve this MfE guidelines suggest using a simple screening test to tell councils whether or not they need to conduct a full risk assessment using more complex scenarios. This report both explains the application of this screening test, and outlines a more complex but more accurate risk assessment method using detailed and catchment-specific weather models, rainfall, river flow, and resulting inundation.
As the details of the impacts on flooding of climate change will be catchment dependent, the specific results from one catchment are unlikely to be indicative for any other catchment. An individual assessment is therefore necessary for each catchment where councils wish to determine the likely impacts of climate change on flood risk. The methodology is designed to be applicable to most catchments larger than an area of 40 by 40 km (1600 km2). It is also designed for a mainly rural setting.
