A lot of work is being done to understand what our future climate might look like, and how this could affect the City of Melbourne's environment, people, and economy. This work describes a system full of interacting and moving parts, each with their own uncertainties and feedback loops. It's complex stuff.
The adaptation cost curve aims to connect the data, information and knowledge we already have. It builds a simplified model of the real world that lets us play with key assumptions and make connections that helps us better understand how climate change and actions for adaptation fit together. The model scaffolding and analysis that support the cost curve can help to:
Tell us about how the actions we are already taking are helping the city adapt to climate change; and
Support decisions about future actions and strategies that help us better adapt the municipality to climate change.
In this section we outline an approach to considering the benefits of adaptation. It is a model-based approach that organises and connects what we know about climate change, with the different types of options we have for adapt. Although the framework includes many indicators that can be refined and added to over time, it is not intended to be 'comprehensive' version of reality. Instead, we focus on modeling the most practical and meaningful components of climate change adaptation to make better sense of how the system behaves.
A model of adaptation value weaves together expert input, longitudinal datasets, simplifying assumptions, and practical judgments. It very quickly becomes very complex. However the logic and algorithms used can be illustrated in very human terms by thinking about how climate change and adaptation actions 'fits' with what we experience, and what we can influence.
You can step though these concepts (and others on this site) by clicking through the green buttons above. Alternatively, you can use the menu navigation or scroll down to move ahead and learn more about how we might 'measure' the impacts of climate change and the value of adaptation actions.
There are numerous ways to think about climate change adaptation: most are highly nuanced but all talk about quite abstract concepts like response measures, vulnerability, resilience, and systems. To make things (a bit) simpler, we'll be thinking about adaptation as a combination of measures that: reduce risk from climate hazards, and build resilience of the municipality to climate change. These are two quite different lenses that operate in the same system that binds the City's people, environment and economy.
So we need to find a way to consider both of these types of adaptation benefit. Let's start with climate risk...
In this section we outline a lineage of research and inputs that could support a framework of adaptation risk indicators and resilience criteria. On the surface this would seem like a 'theoretical' framework, however its scope and detail have been shaped by and designed for the City of Melbourne's influence and decision making process.
The more quantifiable lens of risk is modeled using a 'reference case' which represents the future risk from extreme climate events if no additional adaptation actions are implemented. Put another way, this is the risk from extreme climate if we continue to do only what we are doing now.
The economic value of risk is limited to: i) damage to commercial and residential buildings; ii) damage to civil infrastructure; iii) business productivity loss from lost employee time (i.e. from climate-related disruptions and delays); and iv) increased costs of energy for cooling.
A reference case for social risk measures (heat-related deaths and disrupted services) is also presented, together with a set of resilience criteria for adaptation actions. These non-economic perspectives are critical to help us identify and recognise the more intangible value of adaptation.
Resilience to climate change is a difficult concept to define, let alone measure. One way to to think about resilience is the capacity of a 'system' to absorb shocks, bounce back, evolve and transform. These ideas are not easy to quantify and are frequently woven into measures and actions that also reduce risk. However what we intuitively know however is that there is value in raising the resilience of people, environment and economy to climate risk.
In contrast to risk or avoided loss, we can think about resilience through a 'positive' lens. There is no 'stopping rule' for raising the level of resilience. And there is no baseline measure(s) of resilience. Instead, we need to think about improving resilience at the action level. The six resilience 'criteria' that are illustrated here are designed to be used alongside the risk indicators to better capture the broader adaptation benefit of individual actions.
In this movement we apply the adaption risk and resilience framework to a set of current, planned and 'speculative' City of Melbourne actions.
Many of the actions the City of Melbourne are taking are already helping to adapt the municipality to climate risks. Most of these actions are not driven by long-term adaptation concerns alone but do contain some 'co-benefit' for adaptation. This adaptation benefit is what we're trying to value here. We're isolating this component because we want to develop an evidence-based approach for thinking about and comparing adaptation actions.
With this in mind it is important to remember the adaptation value is additional part to a full 'business case'. Or put another way, you could think of this value as adaptation lens for comparing and actions.
The City of Melbourne has identified over 100 current and planned actions that have adaptation value: by reducing risk or raising resilience to climate change. So what are they? And what can they us about how Council is currently adapting climate change?
In this section we'll take a closer look at the diverse range of adaptation actions and the challenges this presents in applying a consistent and comparable way of thinking about different actions. Let's start by taking a look at what the adaptation actions are and how they could be grouped.
This visualisation breaks down Councils adaptation actions in different ways. The size of each circle representing how likely an action is to be suited to being 'modeled' for adaptation risk. You can view the name of each action by hovering over them. The colours represent work streams of:
You can use this page to view a snapshot of descriptions, approach and key modeling assumptions made for currently modeled actions.
About the action
Adaptation costs and risk benefits
Key risk model assumptions
In this final movement we explore how might we make this modeling and way of thinking useful to City of Melbourne staff and decision makers?
We take a visual and interactive approach to exploring the outputs of the action modeling, to make sense of what the 'numbers' are really telling us. Our starting point is a 'cost curve' - a tool widely used in economics - which ranks actions by their cost-effectiveness for economic risk reduction. This is a powerful decision support and communication tool but abstracts away most of the critical detail and systems thinking applied to this adaptation benefit framework.
To enhance the cost curve, we can add layers of social risk and our resilience criteria to help you understand the real texture behind the raw economic numbers. These lenses provide different perspectives and insights into the how to compare adaptation actions, and the City of Melbourne progressing towards adapting the municipality to climate change.
The adaptation cost curve provides a number of different views and perspectives on the value of adaptation actions. Although there are social indicators and resilience criteria overlaid to this curve, it starting point is based in economic risk reduction - a language that is familiar, quantifiable and most easily recognised in the existing decision making paradigm.
As an addendum to the cost curve, we can look either delve deeper into the numbers - the risk reduction outputs of the modeling - or look at further ways to view and compare actions across the multiple risk and resilience criteria we have sought to measure. The two pages available in this section are provided for you to take your exploration in either of these directions.
Below is a lo-fi prototype visualisation to help explore performance across risk and resilience dimensions. Each line represents an action with 'higher' lines indicator high relative performance against a criteria. Patterns can be explored using the movable and brushable axes. ITooltips and colour to identify actions coding will be added to make this easier to use!.
Modeled risk reduction actions - which totaled around 20 out of 40 better candidates, and included potential future actions - are expected to reduce economic climate risks by around a quarter, and could reduce heat related deaths by around 40% to 2100.
Current risk in 2015
Hot day: $0.5m
Very hot day: $1.1m
Minor flood: $180m
Medium flood: $360m
Major flood: $3,050m
And in 2015
Hot day: $1.2m (+160%)
Very hot day: $2.6m (+138%)
Minor flood: $190m (+2.7%)
Medium flood: $370m (+4.6%)
Major flood: $3,190m (+4.7%)
(adjusted for hazard frequency)
Current annual risk in 2015
Estimated to be around $56m
Between $82m and $92m (Median +27%)
Between $118m and $158m (Median +94%)
Between $141m and $224m (Median +163%)
Estimated risk reduction
from modeled actions
By headline risk indicator
Economic value: ~27%
Heat-related mortality: ~45%
Economic value by risk
Economic value by indicator area
Business productivity: ~13%
Energy and water costs: ~43%
Damage to commercial buildings: ~19%
Damage to civil infrastructure: ~57%
Damage to residential buildings ~50%
Note: all figures are ESTIMATES subject to modeled inputs and assumptions and are presented in $2015 terms