GLOSSARY

Adaptation - Adaptation means taking measures to reduce the impact of flooding.

ARI - Average recurrence interval is the expected time between the events that exceed the given value (rainfall, water level, wave height, etc). It is also known as the "return period" and is usually expressed in years. For example, 1 in 100 rainfall experienced during a storm will, on average, only be once every 100 years. However, it does not mean it cannot happen more or less frequently than every 100 years.

Benefit cost ratio (BCR) - Measures the return benefit received per dollar of costs. The BCR is calculated by dividing the present value of all benefits by the present value of all costs. The BCR is a measure of the proportional return on invested funds.

Monte Carlo Analysis

A technique which randomly samples values from a pre-determined distribution or range to account for uncertainty with that value. In this study, all input parameters have uncertainty. Monte Carlo simulation samples values for each item, recalculates the cost and benefits, and then repeats the process tens of thousands of times. The results are then aggregated, and a distribution of all sampled results generated.

LIDAR - Light detection and ranging is a technology that uses laser pulses to generate large amounts of data about the physical layout of terrain and landscape features.

The data can be analysed and used in diverse applications such as:

• Mapping areas for building and structures in the construction industry;
• Generation of digital terrain maps for use in geographic information systems; and
• Generation of digital vegetation maps for use in the forestry and land management industries.

Net present value (NPV) - Measures the difference between benefits and costs, whilst accounting for the timing of benefits and costs. It is equal to the difference between the present value of benefits and the present value of costs. The NPV is a measure of the absolute return on invested funds. A project with a NPV value greater than zero would be considered economically desirable, with the project having the highest modelled NPV being the most economically desirable.

Storm surge - A temporary increase in sea level above the level of the predicted tide. It is most severe during extreme weather when strong winds push along the water's surface and cause it to accumulate near the coastline. When the slope of the seabed is shallow, storm surge will be higher than if the water was deep.