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CLIMsystems Blog

Extreme Precipitation and Climate Change – You Have Problems – We Have Solutions

Author: Peter Urich

Welcome to the CLIMsystems Blog: Extreme Rainfall Analysis

This is our inaugural blog on the CLIMsystems website. We will regularly post interesting articles on cutting edge climate science, tools and applications that support good decision making in line with our mission statement ‘Decision Making in Climate Changed World’. With the conclusion of the Paris COP 21 we have seen a marked increase in interest in tackling the complex issues of risk and resilience through adaptation. CLIMsystems has been actively researching, developing and applying methods to assist clients facing the increasing likelihood of extreme precipitation events. Understanding the historical situation is just a start. Infrastructure designs must be viewed through the lens of future climate change. CLIMsystems has a range of approaches that close the gap between problem identification and solution.

There can be considerable confusion on how climate science can be applied to extreme rainfall event analysis. Over the years, through numerous projects, a range of methods have been developed and applied by CLIMsystems around the world. These methods derive the best outcomes for clients based on robust application of the latest CMIP5 daily and sub-daily GCM data. Examples include:

  • The Miami-Dade Ocean Outfall program, where extreme rainfall and sea level rise analysis were integral to setting design parameters for a multi-billion dollar infrastructure design and build.
  • Design risk for new railway infrastructure in Queensland and Sydney to cover rail bed erosion risk and drainage issues from extreme rainfall events in the future.
  • Testing of systems against real world extreme flood events such as the Boulder extreme rainfall event in 2013.
  • Establishing seasonal shifts in rainfall for critical catchment for the Bengaluru, India water and wastewater mast planning activity.

The CLIMsystems team has found very important relationships between short duration extreme rainfall and climate change that should change the way urban drainage, wastewater and other flood mitigation projects are designed. In 2015 we developed new methods for applying sub-daily GCM data for extreme event analysis. Through the analysis of this higher resolution data important changes in intensity for short duration events was established. High intensity – short duration events are proving to be a big issue in urban infrastructure design and water management. We are ready to assist projects where design of new and upgraded water-related infrastructure is required: drainage systems, water retention (deep tunnel) systems, waste water reticulation systems, sewerage treatment facilities and ocean outfall designs.

To demystify the link between the data and real world applications we have devised a handy table. It covers five potential applications of extreme rainfall analysis and specific data and methods that should be applied. Importantly, there is not one approach to extreme rainfall analysis that applies to all problems. Methods vary for developing IDF (intensity duration frequency) curves versus processing climate data to link with hydrological models for running flood studies. CLIMsystems is a world leader in methodological developments and processing of the latest GCM/RCM data for the various client driven problem sets.

Download the summary table here. Contact us to discuss your project be it large or small. We can assist.

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