Tag Archives: urban heat island

Cities Taking On Extreme Heat Down Under

Research commissioned by the City of Melbourne as part of its Climate Change Adaptation Strategy found that a January heat wave cost local businesses approximately $37 million.  City administrators know that with the increased frequency and intensity of heatwaves, they need to understand of the economic impacts of such events on businesses.  From theCity of Melbourne

City of Melbourne Environment portfolio chair, Councillor Arron Wood, said Council is firmly focused on building Melbourne’s resilience to climate impacts.

“We’re doubling tree canopy cover for our urban forest, upgrading drainage infrastructure, funding more energy efficient buildings, implementing planning processes to minimise climate risk and installing various water-sensitive urban design initiatives.  Heatwaves don’t only impact our city economically, heat related illness also kills more Australian’s each year than any other natural disaster so City of Melbourne has identified this as a priority issue we must prepare better for,” Cr Wood said.

Meanwhile, the City of Sydney is conducting a trial to see if lighter colored pavement will help reduce the urban heat island effect and improve the comfort and health of the people who live there.  From Australia’s Business Insider:

“Materials such as concrete and cement store more heat than natural surfaces, absorbing it during the day and releasing it at night, which can contribute to hotter urban areas,  . . .  Lighter coloured pavements may result in lower energy bills for surrounding buildings.”

Extreme Heat Triggers Power and Water Cuts in Northern India

A record-breaking heat wave hit northern India in June as temperatures reached 120 degrees.  The power authority couldn’t meet the increased energy demand which has led to power and water cuts throughout the region.

Protesters took to the streets over the lack of basic services and attacked power sub stations, taking several workers hostage, and many companies are keeping workers indoors during the mid-day peak heat.  The extreme heat has also resulted in many deaths among the homeless, elderly and other vulnerable populations.

IPCC Report: Cool Roofs Help Reduce Urban Heat

The Intergovernmental Panel on Climate Change brought together 235 authors from 58 nations to map out strategies for mitigating the impact of climate change.  The buildings section of their report notes that sixty percent of urban surfaces are covered by pavement or rooftops, and that cool roofs can help reduce energy demand, lower temperatures within buildings, improve air quality, and lessen the impact of the urban heat island effect in cities around the world.

Cool Pavements Explained in 2 Minutes

Dark surfaces absorb sunlight and heat. Reflective surfaces help bounce heat away from our
cities. What works with roofs works with roads and parking

Lawrence Berkeley Lab and UC Davis researchers explain
how cool pavements work to cool our cities and improve
the health of the people living in urban areas.  Take a look.


Decreased air temperature.
Increased air quality.
Improved public health.

They all add up to make life in the city more comfortable.

GSEP Helps Mexico Identify Energy and Emission Savings from Cool Roofs

A national study involving 7 major cities covering each of Mexico’s 6 climate zones, found that cool roofs could help commercial and residential buildings reduce energy consumption by 7 to 18 percent.  The study also found that if cool roof technology were used in just three of the cities studied, it could result in the carbon pollution savings of taking 480,000 cars off the roads, and that these cool roof investments would pay for themselves within 3 years.  It is hoped that studies such as this will help raise global awareness of the energy saving potential of cool surfaces, and help drive supportive policies and market growth for these technologies.

The study was conducted as part of a comprehensive “Cool Roofs Action Plan” developed through support from the Clean Energy Ministerial’s Global Superior Energy Performance Partnership (GSEP).  The Global Cool Cities Alliance (GCCA) is coordinating GSEP’s Cool Roofs and Pavements Working Group, and GCCA’s Executive Director, Kurt Shickman is one of the authors of this study.  You can learn more about GCCA’s work on GSEP here.

Rising Urban Temperatures and Air Conditioners

Look at any urban street under the blazing hot July sun, and you’ll think of high daytime temperatures and unbearable heat.  It’s a vicious circle.  As summer approaches and temperatures rise, we crank up the AC to stay cool indoors.  Our air conditioner pumps out heat exhaust, which adds to the urban heat island effect in our cities.  But at least things cool down at night – right?

Maybe not… A recent study by a team of researchers at Arizona State University (ASU) tells us that – as things heat up in the city during the day, the air conditioners we run at night are still adding to the overall urban heat island effect.  They also found that nighttime exhaust has a greater effect on overall temperatures.

From ASU’s press release:

They found that the effect of the AC systems was more important during the night due to the limited depth of the urban boundary layer.  The effect is stronger from late afternoon to early morning.  A smaller quantity of excess AC systems heat ejected during the night can increase the air temperature more compared to a greater quantity released during the daytime when the hot sun is beating down.

You can find the full report HERE.

White Roofs Seen as Part of the Solution

Many people head for the thermostat to cool things down indoors when it gets hot outside.  The problem is, running our air conditioner only makes the problem worse by adding to the strain on an already overworked energy grid, and increasing the amount of carbon in the air.  This is especially true during extreme heat events.  And for vulnerable populations without access to air conditioning, extreme heat could be – and often is – life-threatening.

That’s why cities are looking at other ways to naturally reduce the urban heat island effect.  White roofs, reflective surfaces, and planting trees all add up to cooler temperatures as we deal with the increasingly real effects of climate change.

Read more about the problem in northern climates, and see what Toronto is doing about it.

Cool Surfaces and Social Justice

Heat kills more than 1,500 people in the U.S. each year – more than any type of other natural disaster.  In many cities around the world, it’s not uncommon to find that people in the most disadvantaged neighborhoods are often the most vulnerable to heat.

New research highlights just how vulnerable poor and minority communities are to urban heat.  Cities such asToronto and Washington, DC have identified opportunities to improve environmental and social justice by mitigating their urban heat islands.

Extreme Heat Hits Northern Cities Too

Several recent reports have shed light on the many ways climate change is affecting our way of life, and these reports have people talking about strategies for dealing with extreme heat and the resulting health problems.  We expect extreme heat events down in Atlanta, GA or Los Angeles, CA.  But we’re also hearing of concerns over the urban heat island effect and extreme heat in northern cities like Minneapolis, MN and Chicago, IL.

Atlanta is better able to handle these extreme heat events, with most buildings and homes equipped with air conditioning units.  But cities further north may not have the cooling infrastructure to handle more extreme heat waves.  Schools (which don’t have air conditioning) are shut down and children stay home.  People living on the top floors of un-air conditioned buildings are in greater danger of illness or even death from this extreme heat.

Extreme heat is also affecting places like London, England, and studies tell us that unless something’s done to mitigate the impact of climate change, mortality will increase significantly.   London could be looking at 800 deaths per year by 2050.  Another study tells us that London could see their heat-related mortality rate jump 257% by 2050 unless steps are taken to address the effects of extreme urban heat.

The good news is that more people are beginning to understand that – even in cooler climates such as London –cool roofs can bring down the temperature in buildings, increasing comfort and reducing the chance of heat-related illness and death.  It also brings down energy consumption, which means less carbon in our atmosphere.

You can learn more about extreme heat around the United States, by visiting NOAA’s extreme heat tracking site HERE.

Hot Town – Summer in the (Twin) Cities

Climate change and the urban heat island effect are heating things up in cities around the world.  That’s not surprising in places like Los Angeles and Atlanta, but they’re finding it too hot to handle in northern cities as well.

Researchers are collecting data on urban temperatures in Minneapolis / St. Paul, Minnesota (Twin Cities), and they’re finding cooler temperatures in areas with more vegetation and reflective surfaces.  They’re hoping this data will help them map out strategies for mitigating the effects of climate change in northern climates.  Part of their strategy includes installing more green and white rooftops and planting trees throughout the Twin Cities.

A National Science Foundation grant will help set up studies in other cities around the country to measure the urban heat island effect.

You can read more about it at:
Can’t take the heat? Get out of the city