Tag Archives: cool pavement

Studies Draw Direct Line from Climate Change to Extreme Heat and Drought

A new report from the Climate Council of Australia confirms what many have long suspected – that human-caused climate change makes heat waves more certain and more extreme. 2013 was the hottest year on record in Australia, and as this report notes, the 2012 / 2013 heat waves would have been “virtually impossible” without the release of human-made greenhouse gas emissions into our atmosphere.

It also found that climate change tripled the odds that the heat waves would occur as frequently as they did, and doubled the odds that they would be as intense as they were. More than 123 temperature records were broken during that summer, and the author of the report – Will Steffen – said that these temperatures will seem cool by 2090 unless we act now.

Thankfully, Australia is already using reflective technology to help bring temperatures down. In the City of Melbourne, City administrators know that with the increased frequency and intensity of heatwaves, they need to understand the economic impacts of such events on businesses. From the City of Melbourne

“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.

People on the west coast of the United States are also feeling the effects of climate change. A recent study published in the Proceedings of the National Academy of Science shows that greenhouse gas emissions have increased the likelihood of warm, dry conditions in California, and that by 2030, the warm weather driving the current drought could occur annually.

This problem isn’t just confined to California. According to The National Integrated Drought Information System (Drought.gov), 32% of contiguous USA is in moderate or worse drought.

Thankfully, cities in the Golden State are already on it. A new law went into effect in the city of Los Angeles last year that requires white roofs on all new construction and major rebuilds of residential buildings. Commercial and residential buildings are now required to employ reflective roof technology to help bring city temperatures down. The cities of Pasadena and Hermosa Beach have enacted similar regulations – you can read more about it here.

The problems brought on by extreme heat and climate change are many. But many city leaders around the world are recognizing the benefits of reflective roofs and pavements, and are using this technology to conserve energy, reduce emissions, and save lives.

GCCA Executive Director Kurt Shickman on WAMU’s Metro Connection

Johnathan Wilson, environmental reporter for WAMU (a public radio station in Washington, DC) recently spoke with GCCA Executive Director, Kurt Shickman about rising global temperatures. Kurt talked about the dangers urban heat islands present to people living in cities like Washington, DC, and explained how reflective surfaces and increased vegetation help save lives in extreme heat events.

He also demonstrated how dark surfaces (black roofs) can be as much as 65 degrees hotter than lighter surfaces (white roofs).

You can listen to this WAMU broadcast here, and read a recent GCCA report about how urban heat island heat reduction strategies can help reduce mortality in cities like Washington, DC.

4 ways your city can be cooler next summer

This summer was a scorcher. Heat waves repeatedly struck the Midwest and South, sparing only sections of the Northeast. All of California is still in a drought. Cities were especially hot due to their concentration of buildings and human activity, a phenomenon called the urban heat island effect. At times, it may have felt impossible to beat the heat. Luckily, a recent report from ACEEE and the Global Cool Cities Alliance, Cool Policies for Cool Cities, shows how local governments enable communities to beat the heat before it starts. By employing the following cooling and energy-efficient practices before next summer, cities across North America can keep their cool:

Plant a Tree. A Chinese proverb says, “The best time to plant a tree was 20 years ago. The second best time is now.” Older trees with broad leaves and reaching branches provide a lot of shade for parks, pavements, homes, and offices, helping to keep them cool. They also clean the air and produce oxygen. Local governments often plant trees on city land, but did you know that many cities also provide free or discounted trees for planting on private land?

The Million Trees NYC program provides free trees to property owners, and runs a hotline for residents to call requesting a street tree be planted on their block.
Portland, Oregon offers a “Treebate” in the form of a $15-50 water bill credit to property owners who plant a tree on their land.
Grow Boston Greener offers a $2,500 grant competition to fund tree planting in selected neighborhoods.

Paint your roof. Dark-colored roofs trap and store heat. This heat radiates into the building, and doesn’t dissipate at night. Trapped heat is unpleasant and costly for residents who are forced to crank their AC, and is dangerous,sometimes deadly, for residents who don’t have access to air conditioning. A light-colored or reflective roof traps and stores considerably less heat. Cool roofs, for the same price as dark roofs, reflect the sun’s rays back out into the atmosphere. Recognizing the energy-efficient and publicly beneficial nature of cool roofs, some cities (and the entire State of California) require or encourage new and updated roofs to be reflective.

New and updated roofs in Los Angeles are required to meet a standard reflectiveness. To reduce the cost even further, LA’s Department of Water and Power offers a rebate of $0.20 to $0.30 per square foot.
St. Louis provides an innovative, low-cost financing option called Set the PACE St. Louis for residents replacing their traditional roof with one meeting a reflectiveness standard.

Replace dark pavement. Dark pavements also absorb, trap, and slowly release heat. You’ve experienced this running barefoot across a blacktop basketball court or parking lot. Light pavement, on the other hand, can be 50°-70°F cooler. Replacing dark pavement with vegetation also reduces the urban heat island effect. Grass and other permeable surfaces keep a city’s temperature down compared to pavement. As a bonus, they also filter stormwater. Cities have begun to encourage residents to paint parking lots, play areas, and alleyways with reflective coatings, or replace them with porous materials.

Chicago’s Green Alleys program transforms traditional alleyways into permeable ones. The program also empowers residents to derive more benefit from their green alleyways through pamphlets about landscaping and maintenance techniques.
Washington D.C.’s Riversmart programs enable individuals and communities to replace dark pavement and build green stormwater infrastructure through a series of grants and rebates.
Philadelphia offers stormwater bill credits to commercial property owners that install green stormwater infrastructure.

Vegetate your roof. A green roof eliminates the negative heat effects of a dark roof, and adds the benefits of oxygen exchange, amenity space, and opportunity for urban agriculture. Building a vegetated roof may seem like an expensive project, but many local governments are willing to share your costs.

Toronto, Ontario offers the Eco-Roof Incentive, a $75 per square meter rebate to help residents and businesses complete a green roof project.
Austin encourages green roofs by offering a variety of credits to developers for open space, parkland, and stormwater management. Density bonuses are also available.
Residents of Cincinnati may apply for a below-market-rate loan to install a vegetated roof. This is an effort through the Ohio EPA, the Metropolitan Sewer District of Greater Cincinnati, and the Cincinnati Office of Environmental & Sustainability.

Many local governments already do their part to reduce the urban heat island effect on their own properties, and some provide resources to help members of their communities do their part as well. Although the cities mentioned in this post (and many, many others!) are taking steps to reduce the urban heat island effect, every community can do more. An important driver of increasing urban heat island mitigation policies within a community is citizen demand. Strong private demand can help any of these cool technologies become standard market practice. Investing in cool technologies and buildings makes a community pleasant for all its inhabitants and visitors! Interested in learning more or cooling down your own city? First, check out the report to see what your city is doing to create a cool community. Next, participate in the programs that are available. If you aren’t impressed with what is offered, get involved and ask your city to keep its cool.

Originally posted on ACEEE’s blog: http://aceee.org/blog/2014/08/4-ways-your-city-can-be-cooler-next-s

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.”

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
lots.

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.

GCCA Releases Cool Surfaces Retrospective 2013

Periodically, the Global Cool Cities Alliance will highlight trending topics covering a wide range of urban heat island-related issues in a feature we call Cool Retrospective. For our inaugural issue, we review cool developments in 2013.

2013 saw a number of cities make huge strides to mitigate the impacts of excess urban heat by adopting new cool surface policies. New studies identified the economic advantages of cool roofing and highlighted other critical benefits of reducing urban heat islands.

You can read all about it HERE.