By Jacqueline Balston and David Jenkins*
Climate change is now accepted by asset managers worldwide as a hazard that will diminish the resilience of their infrastructure and a problem that requires increasing effort to reduce our carbon footprint.
Over the past 100 years, humankind has burned approximately 1800 billion barrels of oil, 377 billion tonnes of coal, 150,000 billion cubic meters of gas and cut down 46 percent of all trees on earth.
As a result, 1.5 trillion tonnes of CO2 have been released into the atmosphere since 1751 and levels are now higher than at any other time in the past 800,000 years – and rising rapidly. Added to the CO2 are the emissions of other greenhouse gasses including methane and nitrous oxide.
Higher atmospheric greenhouse gas levels trap solar heat in the lower levels of the atmosphere and, as a result, increase average and extreme temperatures, cyclone intensity, humidity and rainfall (especially in the tropical regions), the frequency and severity of drought, and bushfire weather.
In the oceans, CO2 forms carbonic acid that reduces the pH of the water, the warmer water expands, land-based ice caps and glaciers melt, and the sea level rises. Evidence for all these changes is now well documented and the damage to infrastructure is increasing.
As detailed in the IPWEA Practice Note 12.1, Climate change impacts on the useful life of infrastructure, the impacts to infrastructure include accelerated carbonation, expansion and cracking of concrete, hardening and bleeding of bitumen, expansion and buckling of steel pipelines and railway lines and damage to coastal and other assets.
The Practice Note also examines how climate change may affect the useful life of the asset and provides a process for estimating the impacts of climate change on a range of asset components using a Decision Tree Worksheet and supporting tables.
In addition, a ‘Climate Resilience Design Guide’ currently in development will enable asset managers to identify options that will extend the useful life of an asset, reduce maintenance costs and provide the co-benefits of reducing heat island effects and minimising embodied greenhouse gas emissions.
For more information on the Practice Note 12.1 or any other IPWEA publications go to: ipwea.org/bookshop
*Jacqueline Balston is Director of Sustainability and David Jenkins is Chief Execitive Officer IPWEA Australasia
