Urban heat – A serious health threat now

Image from The Age, Heat is on to combat climate change’s silent killer, 18/08/14 (click image to read article)

“Currently, heat related deaths in Victoria exceed the average annual road toll.

Projections indicate that by 2050 an extreme heat event in Melbourne could kill over one thousand people in a few days if we don’t improve the way we forecast, prepare for and manage these events.” According to the City of Melbourne’s, Urban Forest Strategy.

In September 2014 the ABC reported, “while 173 people died in the Black Saturday fires, for example, 374 people died from heat stress around that time” and according to  Lateline  there were, “more than 1,000 other emergency callouts, blackouts, mass public transport strandings, bushfires” and violence was up”.

It isn’t just Victoria, heat related deaths kill more people than road accidents in
WA and the rest of Australia too.

Heatwaves are an increasing problem all over the world and Perth is no exception.  According to a Climate Council report titled, ‘Heatwaves: Hotter, Longer, More Often, heatwaves are, “defined as a period of at least three days where the combined effect of high temperatures and excess heat is unusual within the local climate.”

The US EPA Excessive Heat Events Guidebook   lists the following people as being at risk;

• Older persons (age > 65)
• Infants (age < 1)
• The homeless
• The poor
• People who are socially isolated
• People with mobility restrictions
• People with mental impairments
• People taking certain medications (e.g., for high blood pressure, depression, insomnia)
• People who are ill or have certain medical conditions (heart, diabetes, kidneys or anything to do with poor circulation)
• People work out doors
• Athletes
• Those under the influence of alcohol or drugs (especially amphetamines and methamphetamines).

Unfortunately, air conditioning can not always be relied on.   For a start not everyone has air conditioning or even electricity.  A study in 2015 by the Consumer Action Law Centre  for example, revealed that “disconnections in Victoria increased from 9,598 electricity disconnections in 2008-09 to 34,448 in 2013-14, an increase of 359%”.  If our economy worsens, so will the number of disconnections in WA?

Blackouts are common during heat waves for a variety of reasons; summer storms, fires, overheating of power generator station equipment, air conditioners breaking down, the list goes on…

There are many economic costs associated with heatwaves, this  article about India’s recent killer heatwave lays out the negative impacts.  Workers without air conditioning sleep badly and this effects productivity.  People who work out doors are often forced to stop work.

What can we do?

Heat is worse in built up areas where there are no trees or vegetation, this phenomenon is called the ‘Urban Heat Island Effect‘, also here described here by NASA scientists;

So rising heat isn’t just caused by climate change, we are making our suburbs hotter by removing trees and greenery.  It has been establish science for years that trees especially and greenery are the most simple and effective way to mitigate urban heat.  See NASA’s article from 2009 titled – Ecosystem, Vegetation Affect Intensity of Urban Heat Island Effect.

According to Perth based urban forest scientist Dr Paul Barber,

“Leafy suburbs can be 6 degrees cooler by mid morning in summer, compared to new treeless suburbs, which can be as hot as the airport.”

Pubic health scientists warn that, “Building resilience to extreme heat events, especially for the most vulnerable groups, is a priority. Public health professionals and executives need to be aware of the very real and urgent need to act now.”

In response to these warnings Local Governments in progressive cities all over the world have created Urban Forest Strategies, with effective action plans, to increase their urban trees canopies and cool their cities to protect their citizens.   Following are some examples from cities, hundreds of smaller Local Governments are also doing them;

• City of Melbourne
• City of Sydney
• City of Chicago
• San Francisco 
• City of Seattle
• City of Portland
• City of Sydney
• London (Canada)
• Toronto
• City of Vancouver

In WA;

• City of Belmont
• City of Armadale
• City of Albany (see section 5.2)

We believed that the Cities of Perth, Subiaco and Fremantle are currently developing Urban Forest Strategies and the City of Melville has just announced it wants to do one too.

Lets hope the City of Stirling will adopt a comprehensive and effective Urban Forest Strategy soon?

More information;

• 202020 Vision report: Where are all of the trees 
• HOW TO GROW AN URBAN FOREST A ten-step guide to help councils save money, time and share practical knowledge.
• City of Melbourne –   Australian first guide for urban forestry      202020 Vision Plan
• Urban Heat Island Report: City of Greater Geelong and Wyndham City Council
• Urban Forest of Perth and Peel (CSIRO report WA Department of Planning)
• Cool communities: Urban trees, climate and health (Curtin Uni)
• Sustainable Singapore Blue Print 2015‘ Biophilic Urbanism with Professor Peter Newman’
• Every Tree Counts: A Portrait of Toronto’s Urban Forest
• Biophilic Cities