AIRBORNE laser systems should be used to more accurately assess the risk of flooding, according to a report from the US National Research Council.
The US is spending more than $200 million a year to upgrade and digitise flood-plain maps used for emergency planning and insurance. However, existing data on land elevation is not good enough to provide accurate maps of areas at risk, the report says.
Measurements should be to within 30 centimetres in flat areas, more than 10 times as accurate as existing figures, which are decades old. Firing laser pulses from low-flying aircraft and measuring the time…
