Download Climate change impact assessment

CLIMATE CHANGE IMPACT ASSESSMENT - THE SYDNEY CATCHMENT AUTHORITY’S APPROACH
Greg Greene1, Graham Begg1,
1
. Sydney Catchment Authority, Penrith, NSW, Australia
INTRODUCTION
A collaborative study on the projected impact of climate change on water supply and demand was been
undertaken to inform the 2004 (Sydney) Metropolitan Water Plan and subsequent revisions. However, the
risks imposed by climate change with respect to land use, water quality and infrastructure are much wider
than that covered by this study. To assess the broader implications of climate change on the Sydney
Catchment Authority (SCA), a qualitative and semi-quantitative risk assessment was completed in 2010. This
assessment examined the implications of climate change adaptation on the SCA’s infrastructure, water
supply and catchment land use, and how this may affect the organisation’s business planning. Two future
climate scenarios, based on recent climate change projections covering SCA catchment areas, were used to
guide internal experts in identifying key vulnerabilities and the current and additional activities and controls
that help mitigate the potential impacts of climate change. The assessment found that while the SCA has a
high degree of preparedness for many of the potential impacts of climate change, additional investments in
infrastructure, modelling, tools and preparedness is necessary for the SCA. Ten overarching climate change
action statements were developed as a result of the assessment and these have been incorporated into the
SCA’s Corporate Sustainability Strategy, and are also the subject of more detailed investigations and
business planning. This paper will outline the process used in the development of these actions and will
discuss the current progress and direction of the SCA in meeting this significant challenge.
METHODOLOGY
The SCA’s climate change impact assessment involved a series of internal workshops and expert driven
ranking and prioritisation that was informed by an analysis based on primary climate hazard, secondary
hazard and implication analysis. Two representative climate change scenarios were developed for the SCA’s
climate change impact based on recent climate change projections covering SCA catchment areas. These
projections represented plausible climatic conditions that could arise during the next 50 years. The first was
a ‘warmer and stormier’ scenario and the second was a more extreme ‘hot, dry and stormy’ scenario, both
representing scenarios sufficiently different to the current climate and within the range of projected impacts.
Workshops were initially held with specialist senior staff from across the SCA, preceded by a series of
seminars on the science of climate change. The workshops assessed the current understanding of climate
change within the SCA, determined climate assumptions built into operations and planning, and explored the
sensitivity of business operations to projections of climatic extremes. About 1000 potential impacts were
identified and later consolidated into a smaller number of hazard and impact statements relevant to nine key
business theme areas. Adaptation responses were then developed through a series of focused workshops
with specialist SCA staff that reviewed the potential impact statements relevant to each business theme area
and identified existing controls or actions that could lessen or partially address the impact across. This also
allowed a gap analysis to then be undertaken and climate change action statements to be developed.
RESULTS
The impact assessment found that overall, the SCA has a high degree of preparedness for handling many of
the potential impacts of climate change. A range of controls, including operational, procedural and policy,
and inbuilt flexibility is already in place, as a result of the natural high variability, and this can be accelerated
if needed. The assessment did help identify a number of business areas in the SCA where improved
planning, additional investment in infrastructure, modelling, tools and back-up systems could assist in
building adaptive capacity and business resilience. In addition, the assessment reaffirmed that there were
clear limitations with the current climate modelling, downscaling techniques and inability of models to
simulate persistent drought and rain conditions over multiple years which needed to be addressed. The
assessment of business vulnerabilities, existing controls, gaps and potential responses resulted in the
following ten key climate change action statements being developed:
Action 1- Ensuring climate change scenarios are realistic
Action 2 – Reducing the SCA’s carbon footprint
Action 3 – Quantifying the impact of climate change on water quality and quality
Action 4 – Increasing flexibility in the water supply system
Action 5 – Improving SCA’s capacity to monitor short-duration events
Action 6 – Reviewing strategies and plans for sensitivity to climate change scenarios
Action 7 – Reviewing design specifications of existing critical infrastructure
Action 8 – Building explicit consideration of climate change into new business initiatives and project designs
Action 9 Increasing preparedness to manage concurrent or extreme events
Action 10 – Improving communications and knowledge exchange on climate change
Implementation of the actions, as well as a periodic review of their continuing relevance in light of future
climate modelling and work being undertaken by other NSW Government agencies, will be coordinated by
an specialist working group specifically established by the SCA for climate change adaptation.
CONCLUSION
While further work is underway to improve the predictions of climate change impacts across the SCA
catchments, the SCA has been able to realistically assess its business vulnerabilities and identify a number
of business areas in the SCA where improved planning, additional investment in infrastructure, modelling,
tools and back-up systems could assist in building adaptive capacity and business resilience. It has
committed to ten climate change actions that have already influenced the SCA’s business planning and
importantly have been built into the Corporate Sustainability Strategy that provides the SCA’s strategic
direction for the next five years. It has also led to the SCA partnering with the Office of Environment and
Heritage and other agencies to develop a Regional Climate Change Model that will that will generate
detailed climate projections for NSW and the ACT. This work will better enable an assessment of the
potential impact of climate change on water supply system yield and will build greater confidence in planning
for potential climate change futures. The SCA also continues to work with other government agencies to
develop mitigation initiatives as part of a whole-of-government approach to climate change adaptation.