There are a number of reasons that a short narrative is adequate. Perhaps most important is that climate change is in most cases only one piece of the information that is being included in your planning. Those other pieces of information, for example water management policy and population growth, influence how accurately the climate information needs to be known. Also, often there is already familiarity with vulnerabilities due to weather. Therefore, climate change can be looked at as - how will my weather vulnerability change? When you get to a problem this focused, we can often tell you in a general sense how weather is likely to change; however, it is not possible to say how weather will change with great accuracy or confidence. Therefore, taken in the context of your problem and given the reality of the confidence we have in the climate information a short narrative is adequate, at least to start along the planning path.