Where flooding occurs every year or every few years, the hazard becomes part of the landscape, and projects are sited and designed with this constraint in mind, Conversely, in an area where a tsunami may strike any time in the next 50 or 100 years, it is difficult to stimulate interest in vulnerability reduction measures even though the damage may be catastrophic การเปลี่ยนแปลงของเปลือกโลก หายนะ. With so long a time horizon, investment in capital-intensive measures may not be economically viable