April 16, 2020 | Published by | ,

Picture: Looking into the past. Credit: Nomad Tales (Flickr CC BY-SA 2.0)

Extreme rainfall is projected to increase with climate change, but the impact of climate change on floods is uncertain. Infrastructure design based on information available from a short time series (typically ~30 – 80 years) may not take account of the full range of possible flood events.

Australian palaeoflood and palaeohydroclimate records drawn from a wide variety of natural archives and documentary sources suggest Australia has been subjected to larger flood events in the past; an unusually wet period for eastern Australia in the eighteenth Century is particularly note-worthy.

If the current infrastructure is inadequate for past floods, it is unlikely it will adequately mitigate future floods. We discuss how improved awareness, and incorporation, of palaeoflood records in risk-estimates could help guide infrastructure planning and design, flood event prediction and inform flood mitigation policy. This is particularly relevant for Australia with its notoriously variable hydroclimate.