Tuesday, July 22, 2008

Climate change adaptation policies for the City of Melbourne

This interests me – a draft plan for adaptation to climate change in the City of Melbourne. As stewards of their local communities, local governments have a role in assessing and addressing the impacts of climate change.  Note I am interested in the fact that such a plan exists for our local community rather than the specific insights of this draft report. 
Generally cities are seen by this report as likely to be affected by climate change in three key ways:
  • Impacts on resource productivity or changes in market demand for goods and services;
  • Performance of physical infrastructure & industries directly affected by changed climate conditions or damaging extreme events;
  • Populations affected by extreme weather, scarce resources, health status, changed economic conditions or migration.
By 2030 Melbourne is expected to be significantly affected by warmer temperatures and heatwaves, lower rainfall, intense storm events and flash flooding. An adaptation response comprising four policies sought:
  • Loss prevention – actions to reduce vulnerability to climate change;
  • Loss sharing – spreading the risk of loss among a wider population (eg insurance);
  • Behaviour modification – eliminating the activity or behaviour that causes the hazard;
  • Relocation – moving vulnerable population or systems away from hazards induced by climate change.
The City of Melbourne has employed consultants to assess Melbourne’s climate change risks for 2010, 2030 and 2070. The main climatic effects envisaged are:
  • Reduced rainfall and drought;
  • Extreme heatwave;
  • Intense rainfall and wind storm;
  • Sea level rise.
Melbourne is expecting unprecedented population growth to become Australia’s largest capital city by
2030 - population within the CoM is expected to double over this period.
Two key adaptation measures seen as having high value in this draft report are:
  • Stormwater harvesting which can assist in both flash flooding events & insufficient water supply;
  • Increasing passive cooling of the city to reduce the heat island effect.
With respect to the latter Melbourne’s CBD can be 7 degrees higher than other Melbourne suburbs on a hot day. This significant difference substantially heightens the vulnerability of people in the city to heat stress, injury or death. Measures to reduce the city temperature both inside buildings and at street level will provide considerable benefits to reducing overall exposure.
Feedback on this proposal can be submitted by replying to this email, via the online feedback form. I am interested in collecting information on this type of work and thereby increasing my knowledge of climate adaptation to urban and city areas.


Cryptandra said...


The green roofing idea is interesting . Apparently some German cities now mandate it for new buildings. See here: http://www.theaustralian.news.com.au/story/0,25197,23894388-5012694,00.html

and here: http://business.theage.com.au/business/oases-in-the-sky-are-a-growing-trend-in-our-concrete-jungles-20080217-1snk.html?page=2

I also wonder if the albedo of cities could somehow be reduced.

Having said that, the reduction in heating costs in urban heat islands is also a consideration.

Anonymous said...

By 2030 Melbourne is expected to be significantly affected by warmer temperatures and heatwaves, lower rainfall, intense storm events and flash flooding.

So let me get this straight:

Melbourne's weather projection is that there will be droughts, flooding and storms (I presume with rain)

And where supposed to take this seriously, Harry?

Anonymous said...

Less rainfall overall, but what there is will come as intense storms. Why is this so hard to understand?

hc said...

jc, Draw a probability distributiuon for climate and shift the mean a little keeping the same shaped distribution. Notice how the tail arounfd a particular value gets much bigger - more 'extreme' events.

The claims do make basic sense.

Anonymous said...


In terms of the minute information we know about Melbourne weather the description they offer is no different to the weather have now and when I was I child.

Droughts, flooding and intense storms.

Melbourne gets lots of rains through intense storms. If they are predicting intense storms it means we'll end up with lots of rain.

I wonder if these people get a salary for reporting this kind of swill.

Anonymous said...

JC, here it is in terms a primary school student could understand.

Scenario 1: Melbourne has two intense storms per year (50 ml), and 100 other rainy days (10 ml each). Total rainfall 1100 ml.

Scenario 2: Melbourne has four intense storms per year, and 60 other rainy days. Total rainfall 800 ml.

So under scenario 2, there's twice as many intense storms and 300 ml less rain in total.

Anonymous said...


I would be accusing people of being high schoolers when you recently suggested mitigation costs would cost only 1-2% of one years worth of GDP.

Do you know when the first intense storm is going to hit?

Anonymous said...

"Do you know when the first intense storm is going to hit?"

February 3 2005.

Look it up.

Costs of climate change mitigation come from Stern. If you've got better estimates, let's see them.

Anonymous said...

Costs of climate change mitigation come from Stern. If you've got better estimates, let's see them.

Even if you use Sterns pessimistic science scenario while applying a reasonable cost to capital unlike him, the effective mitigation strategy is to do nothing and watch, while allowing GDP to grow unmolested.

Anonymous said...

that was me

Anonymous said...

JC, I've already given you a well-deserved whipping on the storms. Don't make me came after you on mitigation costs as well.

Anonymous said...


Last time I read anything from you about AGW mitigation you were suggesting that the cost is 1-2% of one years GDP. You still hold that view?

Love to continue this debate with you.

Anonymous said...

i really like the green roofing idea i think its an interesting idea and it seems to be working in a few other countries.