Long Term Investment Scenarios (LTIS) report 2019 brought together the understanding of long-term investment scenarios for flood and coastal erosion risk management. It expanded the range of climate change scenarios and included a plausible extreme scenario (high++) in addition to the high, medium and no climate change scenarios of LTIS 2014 and the Met Office's UK Climate Projections 2018 (UKCP18).
Evidence from the new scenarios showed the overall economic optimum level of investment is higher than previously estimated because it uses the range across medium and high climate change scenarios. It also includes a better understanding of the wider impacts of flooding and the investment needed to manage surface water.