Heat Island Effect
Welcome to EPA's Urban Heat Island Newsroom. The Newsroom provides current news and links to news releases related to urban heat island impacts, mitigation strategies, and community initiatives. To help keep you up to date, you may also wish to sign up for EPA's Urban Heat Island Newsletter. Older stories can be found in the Newsroom Archive.
- Executive Order Incentivizes Deployment of Green Infrastructure (March 19, 2015) – President Obama signed an executive order that encourages federal agencies to increase climate resilience through measures such as installing green infrastructure on federal properties to manage stormwater and wastewater.
- U.S. Forest Service Examines Environmental Benefits of Green Spaces Across Income Levels (March 19, 2015) – A new U.S. Forest Service review found that lower-income groups tend to have worse health outcomes and are less likely to live near green space. The review makes recommendations for addressing research gaps related to income inequality and access to green space, including how ecosystem services—especially those related to social interactions, physical activity, and climate adaptation—are being assessed in disadvantaged communities; examining the role of green space programing on sense of place; and investigating how changes to green space influence the level of outdoor physical activity.
- Study Finds Water Works Park in Des Moines, Iowa, Delivers $370,000 in Annual Benefits (March 14, 2015) – A tree inventory in Des Moines’s 1,500-acre Water Works Park finds that it provides nearly $370,000 in annual energy reduction, stormwater, air quality, aesthetics, and greenhouse gas reduction benefits.
- Santa Monica School Converts Blackspace into Greenspace (March 7, 2015) – A local Santa Monica School converted a large expanse of blacktop into a greenspace for environmental learning, which includes 15 new trees.
- Columbia University Report Finds that Urban Heat Island Effect Lowers Fog in Southern California (March 5, 2015) – Researchers at Columbia University released a study that finds that the urban heat island effect contributed to a 63 percent decrease in fog in Los Angeles over the last 60 years, resulting in reduced water reaching coastal ecosystems. In Ontario, California, the researchers found that fog declined by nearly 90 percent in the same timeframe.
- U.S. Forest Service Releases Report Quantifying Benefits of Urban Forests (February 24, 2015) – The U.S. Forest Service released a report that estimates that trees cover about 35 percent of urban areas, and provide an economic value of $2.4 trillion in reduced air pollution and building shading (which reduces energy costs).
- Seattle Office Building Installs Green Roof (February 18, 2015) – A Seattle company installed a 54,000 square-foot green roof with a rain harvesting tank, resulting in a net project savings of about $70,000.
- Northern Illinois University Researchers Find Urban Heat Island Effect Contributes to More Thunderstorms (February 17, 2015) – In a recent study, researchers at Northern Illinois University found that for any given warm-season day in the 17-year study, there was about a 5 percent greater chance that Atlanta would experience a thunderstorm compared with a similarly sized rural area. The researchers determined that the urban heat island effect contributed to this disparity.
- New York City Department of Environmental Protection Announces Funding for Six Stormwater Management Projects (February 12, 2015) – The New York City Department of Environmental Protection announced that six stormwater management projects will receive $3 million in funding through the Green Infrastructure Grant program. Funded projects include green roofs and rooftop farms.
- Kokomo, Indiana Receives $20,000 Urban Forestry Grant (February 2, 2015) – The Kokomo Parks and Recreation Department received a $20,000 grant from the Indiana Department of Natural Resources to perform a comprehensive tree inventory of the City’s 33 parks and install interpretive signs describing the benefits of urban forestry throughout the park system.
- Researchers Find Cities Are Becoming Hotter, Less Windy (January 30, 2015) – A new study in the Journal of Environmental Research Letters examined the changing climates of 217 small (population of 250,000) and large (population above 5 million) urban areas around the world between 1973 and 2012. The study finds that 48 percent of the cities showed an increased trend toward more extreme hot days, compared to only 2 percent that saw a decrease. The study also finds that 75 percent of the urban areas saw declines in extreme windy days, while only 10 percent saw an increase.
- Greater Chicago Metropolitan Water Reclamation District Installs Green Roof (January 29, 2015) – The Metropolitan Water Reclamation District of Greater Chicago installed a green roof at the Racine Avenue Pumping Station. The roof occupies 4,500 square feet, uses weather-resistant plants, reduces stormwater runoff, and lowers heating costs.
- Urban Tree Growth & Longevity Working Group Releases Study on Urban Tree Data (January 26, 2015) – The Urban Tree Growth & Longevity Working Group—an independent collaboration of scientists and professionals—released a study that assesses the accuracy of field data collected by minimally trained volunteers and interns.
- Philadelphia Parks Department Launches Three Urban Forestry Experiments (January 23, 2014) – The Philadelphia Parks Department is launching experiments at roughly 30-acre sites in Cobbs Creek and Wissahickon Valley parks to plant tree species capable of surviving in temperature conditions expected at the end of this century.
- Storm Lake, Iowa Receives Grant to Complete Tree Inventory (January 22, 2015) – The Iowa Department of Natural Resources awarded a grant titled “Sustainable Urban Forestry Training and Assistance for Communities over 5,000” to provide training to municipal staff, non-profits, and interested citizens so that Storm Lake can complete a public tree inventory, prepare for Emerald Ash Borer issues, and create a sustainable urban forestry program.
- New York State Department of Environmental Conservation Awards Over $900,000 in Urban Forestry Grants (January 14, 2015) – The New York State Department of Environmental Conservation is awarding nearly $930,000 for 40 urban forestry projects in communities across New York to help protect air, water, and natural resources, and to enhance urban communities.
- University Corporation for Atmospheric Research Scientists Model Urban Heat Island Effect (January 13, 2015) – Scientists from the University Corporation for Atmospheric Research —an earth science research consortium of more than 100 member colleges and universities—have found that differences in air turbulence between rural and urban areas are the primary cause of the daytime urban heat island effect, with the nighttime differences dominated more by differences in vegetation cover.
- Indiana University Examines Urban Tree Survival and Growth (January 10, 2015) – Indiana University researchers are surveying more than 1,300 trees in Indianapolis to understand what characteristics predict survival and growth of trees in neighborhood tree-planting projects. The researchers find that tree size, resident tenure, and correct mulching are positively related to tree success, while high stem diameter (more than 2 inches) at planting, crown dieback, and lower trunk damage are all negatively correlated with tree success.
Pascagoula, Mississippi Awarded $50,000 Grant to Restore Urban Forest (January 8, 2015) – Pascagoula, Mississippi received a $50,000 National Fish and Wildlife Foundation grant under its Five Star and Urban Waters Restoration Program to restore an acre of urban forest, install two rain gardens, and remove one acre of invasive plant species.
- Modesto, California Increases Urban Forestry Spending and Initiatives (January 3, 2015) – The Forestry division of Modesto, California is hiring workers, trimming trees, attacking tree-killing parasites, restarting the city nursery, and planting trees for the first time in nearly 10 years. The division is reallocating about $290,000 from community forestry’s $3 million budget to hire six permanent maintenance workers.
- Portland Enacts Tree Code That Requires Homeowners to Obtain Permissions Before Cutting Down Trees (January 1, 2015) – Portland is adopting a new city tree code designed to require homeowners to obtain a permit to cut down trees, with fines of up to $1000 for those who fail to comply. Portland now becomes one of a growing number of cities in North America to adopt this type of requirement.
- Knoxville, Kentucky to Plant Over 600 Trees (December 19, 2014) – Knoxville, Kentucky is implementing a new urban forestry plan by identifying and selecting the best sites to plant 45 different species of trees in parks, greenways, and rights-of-way.
- Greenpoint, Brooklyn Receives $2 Million Grant to Plant 500 New Trees (December 17, 2014) – Greenpoint, Brooklyn received a $2 million grant from the Greenpoint Community Environmental Fund to plant 500 neighborhood trees. The “Greening Greenpoint” initiative, which is partnering with the MillionTreesNYC program, will also include removing up to 25,000 square feet of impervious concrete around 675 existing tree beds and training 10 high school students to participate in an urban and community forestry paid internship program.
- Savannah River Remediation in Georgia Installs Cool Roofs (December 14, 2014) – Savannah River Remediation in Savannah, Georgia installed two cool roofs on office buildings that are expected to reduce rooftop temperatures from 150 to 100 degrees, with corresponding reductions in cooling costs.
- Idaho Department of Lands Study Examines Ecosystem Benefits of Trees (December 11, 2014) – A study by the Idaho Department of Lands finds that trees provide $900,000 in ecosystem benefits to cities in eastern Idaho, and that there are about 250,000 trees shading 7.6 percent of the area, with a replacement value exceeding $450 million.
- Researchers Examine Efficacy of Low- and No-Cost Tree Planting Programs (December 4, 2014) – Researchers examined tree planting programs in Washington, D.C., and Baltimore, Maryland, and found that free or reduced-cost programs for tree planting on private lands were most effective in the most affluent neighborhoods with the most existing tree canopy. The researchers aim to create a framework for testing which land management strategies are most effective, where, and with whom in order to improve the ability to plan and enhance urban sustainability and resilience through urban forestry.
- Queens, New York Park Collecting Urban Forestry Data (December 3, 2014) – Alley Pond Park in Queens, New York is collecting soil temperature, precipitation, and other data from woodlands as part of the U.S. Forest Service’s “Smart Forests” initiative . Data that previously took months to distribute can now be shared within hours of collection.
- Miami Neighborhoods Receive Grants to Plant 200 Trees (December 2, 2014) – Two Miami-Dade county neighborhoods located in areas with above-average temperatures received $100,000 in grants from the Funders’ Network for Smart Growth and Livable Communities and the Urban Sustainability Directors Network to plant 200 trees as part of the Million Trees Miami campaign.
- New York City, New York Developer Installs 2 Green Roofs (November 26, 2014) – A New York City, New York developer installed two green roofs totaling 20,000 square feet at its Manhattan office building. The roof is intended to improve stormwater retention and reduce the urban heat island effect.
- University of Wisconsin Researchers Examine Causes of Urban Heat Island Effect (November 25, 2014) – University of Wisconsin researchers examined how temperatures in Madison, Wisconsin vary at the neighborhood level. The researchers found that the density of urban development and lack of vegetation had the greatest impact on temperature variation, and that warming within Madison was more pronounced during the summer, and particularly at night, under calm, clear conditions.