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.

• October 2016
  • The Nature Conservancy Releases Study on Impact of Urban Trees on  Heat Islands Exit (October 31, 2016) – The Nature Conservancy released a study finding that an investment in tree planting of $4 per resident in some cities could improve the health of tens of millions of people by reducing air pollution and cooling city streets. The study found that an annual global investment of $100 million in tree planting could provide 77 million people with cooler cities.
  • San Mateo, California, Adopts Ordinance to Require Cool Roofs Installed on New Construction Projects Exit (October 6, 2016) – The city of San Mateo, California, recently passed an ordinance requiring cool roofs to be installed on all new multi-family and commercial developments with low-sloped roofs, starting on January 1^st, 2017.
• September 2016
  • Lawrence Berkeley National Laboratory Scientists Find Ruby Red Roofing Can Stay As Cool as Commercial White Coatings  Exit (September 21, 2016) – Scientists from Lawrence Berkeley National Laboratory’s Heat Island Group found that roofs with a coat of white paint overlaid with a layer of ruby crystals stayed as cool as a commercial white coating. The researchers expect this technology can be used in roofs, vehicles, ships, storage tanks, and PVC piping.
  • American Society of Landscape Architects Produces Guide on Community Actions for Resilient Landscape and Planning Design  Exit (September 19, 2016) – The American Society of Landscape Architects produced a guide designed to explain how communities can better protect themselves from natural disasters, including extreme heat events, through resilient landscape planning and design. The guide includes recommendations such as increasing urban forests to both clean the air and reduce the heat island effect.
  • Minneapolis-St. Paul International Airport Completes Green Roof Project  Exit (September 1, 2016) – The Minneapolis-St. Paul International Airport completed a green roof, a third of a football field in size, on its Terminal 2. The roof incorporates plants that will flower in different seasons, and reduces roof temperatures and rainwater runoff.
• August 2016
  • Arizona State University Researchers Examine Long-Term Solutions to Reduce Heat Island Effect in Phoenix Exit (August 5, 2016) – Researchers at Arizona State University are undertaking a 5-year study examining long-term solutions to reduce the urban heat island effect in Phoenix, Arizona. The study also looks at mitigation measures in nine other Western Hemisphere cities that face risks from extreme weather.
  • Trust for Public Land Using EPA Mapping Tool to Identify Areas Affected by Urban Heat Island Effect  Exit (August 2, 2016) – The non-profit Trust for Public Land is using EJSCREEN, an EPA mapping tool, to locate areas with low levels of green infrastructure that overlap with populations that are especially vulnerable to the heat island effect and flooding (e.g., low-income, people of color). The nonprofit aims to promote green infrastructure in areas vulnerable to both flooding and heat island effect problems to mitigate both problems simultaneously.
  • University of Southern California Study Concludes Switching to Drought-Tolerant Lawns Can Increase Daytime Temperatures But Reduce Nighttime Temperatures By Greater Amount  Exit (August 2, 2016) – A University of Southern California Study concludes that transforming all lawns in Los Angeles to drought-tolerant plants would increase daytime temperatures by up to 3.4 degrees Fahrenheit due to reduced demand for irrigation, which cools off cities. However, the study also found that drought-tolerant lawns can reduce nighttime temperatures in Los Angeles by 5.4 degrees Fahrenheit.
• July 2016
  • Georgia Tech University Researchers Identify Tree Species That Can Withstand Higher Temperatures  Exit (July 11, 2016) – Researchers from Georgia Tech University performed a study examining how changes in urban temperature affect a variety of tree species. The results show that six of 20 metropolitan areas studied lost trees due to the northward shift of hardiness zones, and recommends that heat island mitigation programs focus on planting tree species that can withstand projected higher temperatures in the future.
  • Hospital in New Milford, Connecticut Deploys 6,000-Square Foot Green Roof  Exit (July 2, 2016) – A hospital in New Milford, Connecticut used a $405,000 grant to construct a 6,000-square foot green roof expected to reduce building temperatures and double the roof’s lifetime.
• June 2016
  • Notre Dame University Finds Green and Cool Roofs Can Cool Chicago Roof Temperatures by Up to 4 Degrees Celsius  Exit (June 1, 2016) – Researchers at Notre Dame University published a study finding that installing green and cool roofs on Chicago’s current infrastructure could reduce the urban heat island effect by lowering roof temperatures by between 3 and 4 degrees Celsius.
• May 2016
  • Green Roof Industry Grew by 18.5 Percent in 2015, Washington D.C. Top City for Green Roofs  Exit (May 31, 2016) – Green Roofs for Healthy Cities released its 2015 Annual Green Roof Industry Survey, showing that the North American green roof industry grew by 18.5 percent in 2015. The survey also found that Washington, D.C. is the city with the largest number of green roofs in North America.
  • University of Wisconsin-Madison Research Finds Heat Islands Affect Growing Season  Exit (May 25, 2016) – Researchers at the University of Wisconsin-Madison found that the growing season is up to a week longer in the densest areas of a city than in the surrounding countryside, while urban parks are cooler and their growing seasons are more in sync with those of nearby natural areas. Changes in the length of the growing season—especially the onset of flowering in trees and plants—can affect birds and pollinating insects.
  • Temple University Library Receives $6.7 Million Loan to Deploy Green Infrastructure  Exit (May 3, 2016) – Temple University received a $6.7 million, low-interest loan from Pennsylvania’s Infrastructure Investment Authority to install a green roof, permeable paving, and a rainwater harvesting system for its library.
• April 2016
  • Reno, Nevada Starts ReLEAF Reno Initiative to Increase the City’s Tree Cover and Reduce Urban Heat Island Effect  Exit (April 29, 2016) – The city of Reno, Nevada started the ReLEAF Reno initiative, designed to preserve the health of existing trees, expand the city's urban tree canopy, and mitigate the urban heat island effect.
  • Louisville Releases Urban Heat Island Effect Study, Announces Cool502 Program to Reduce Urban Heat  Exit (April 25, 2016) – Louisville released a study that measures its urban heat island effect and recommends policies to mitigate it. The mayor also announced a “Cool502” program to implement urban heat island mitigation policies.
  • University of Maryland Researchers Complete Study Finding Paved Areas in Washington, D.C. Increased from 22 to 26 Percent Since 1984  Exit (April 13, 2016) – Researchers at the University of Maryland released a study that shows that the percentage of impervious paved areas in Washington, D.C. increased from 22 percent in 1984 to 26 percent in 2010. Increased impervious areas absorb heat and exacerbate the urban heat island effect, resulting in D.C.’s temperature exceeding that of surrounding areas by an average of seven degrees Fahrenheit since 2004.
  • University of Southern California and Arizona State University Scientists Rank Measures to Reduce Pedestrian Heat Exposure  Exit (April 8, 2016) – Scientists from the University of Southern California and Arizona State University released a study ranking measures to cool temperatures for pedestrians, rather than cities as a whole. The study finds that the most effective strategy to improve pedestrian comfort is adding street trees. Cool and green roofs reduce temperatures at the roof, rather than pedestrian level.
• March 2016
  • Kansas University School of Business Installing 7,000-Foot Green Roof  Exit (March 29, 2016) – Kansas University’s School of Business is installing a 7,000-foot green roof composed of drought-tolerant plants intended to encourage student innovation, improve air quality, and reduce the urban heat island effect.
  • Columbus, Ohio Aims to Plant 300,000 Trees to Combat Urban Heat Island Effect  Exit (March 22, 2016) – Columbus, Ohio’s Branch Out Program aims to plant 300,000 trees by 2020 in order to mitigate the urban heat island effect, retain stormwater, and offset projected losses in urban forest cover.
  • Prudential Invests $1.7 million in Washington, D.C. Company to Install Green Infrastructure  Exit (March 18, 2016) – Prudential announced a $1.7 million investment in District Stormwater, a company that installs green infrastructure such as trees, rain gardens, green roofs, permeable surfaces, and bioswales. District Stormwater is able to sell credits from these projects to developers, who are required to purchase credits that reduce stormwater runoff under Washington, D.C. law.
  • Wilmington Historic Building Created 3,500-Square Foot Green Roof  Exit (March 10, 2016) – Wilmington’s Tide Water Power and Light building installed a 3,500-square foot green roof, with other parts of the roof painted white for increased reflectivity of sunlight .
  • U.S. Forest Service Announces Grant Funding for Urban and Community Forestry  Exit (March 1, 2016) – The U.S. Forest Service released a request for pre-proposals for grants to support national urban and community forestry projects on nonfederal public land that have national or multi-state impacts and applications. The deadline is June 17, 2016.
• February 2016
  • American Society of Landscape Architects Produces Video on Impact of Trees on Urban Temperatures and Pollution Exit (February 15, 2016) – The American Society of Landscape Architects developed a video that shows how increasing tree canopy in cities can fight both urban heat and poor air quality.
  • Creating a Plan to Manage Green Roofs Exit (February 1, 2016) – Green roofs need to be fully managed to be successful, but who is responsible and how can they best go about it? This article in the Living Architecture Monitor provides tips and ideas for creating an effective green roof management plan.
• January 2016
  • Microsoft to Construct 4-Acre Green Roof for Campus Exit (January 25, 2016) – Microsoft intends to construct a 3.7 - acre green roof at its campus in Mountain View, California.
  • Lawrence Berkeley Lab Studies Cool Walls Exit (January 12, 2016) – Lawrence Berkeley National Laboratory has teamed up with the University of Southern California and the University of California, San Diego, to study the benefits, performance, and technologies of cool walls.
  • ENERGY STAR Certified Cool Roofing Products Must be Recertified Before July 1, 2017 Exit (January 12, 2016) – The Cool Roof Rating Council announced that all ENERGY STAR certified roofing products should be recertified to ENERGY STAR Version 3.0 before July 1, 2017 in order to remain on ENERGY STAR’s Qualified Products List.
• December 2015
  • Indiana Department of Natural Resources Awards $135,000 in Urban Forestry Grants Exit (December 21, 2015) – The Indiana Department of Natural Resources awarded $135,000 in urban forestry grants involving tree inventory and analysis for management planning, new tree plantings, and education awareness campaigns.
  • Students in Louisville Collect Data on Urban Heat Island Effect Exit (December 11, 2015) – Students at 23 schools across Louisville, Kentucky, are helping to collect data on the urban heat island effect using meteorological stations atop school buildings.
• November 2015
  • Liberty Park in New York City, New York Installing Green Roof (November 24, 2015) – Liberty Park in New York City, New York, is installing a $50 million green roof atop the 25-foot-high entrance to the World Trade Center's vehicle security area.
  • University of Minnesota Completes Urban Heat Island Study (November 17, 2015) – The University of Minnesota released a study finding that urban temperatures in Minneapolis, Minnesota, are on average 2°F higher than surrounding areas, with the difference reaching 9°F during a 2012 heat wave.
  • 40-and-1 Nights: Miami Deals with Record Heat Exit (November 9, 2015) – This news article written by a top Miami meteorologist points to the heat island effect as a likely contributor to the lengthening hot season in the Miami-Ft. Lauderdale region since 1950.
  • Cities are Overheating, and Cooling Them Off Will Be Risky Exit (November 4, 2015) – Tinkering too much with a city’s temperature can create new problems, according to Haider Taha, a heat island expert and the developer of California’s recently published urban heat island index.
• October 2015
  • UC Riverside Analyzes the Benefits of Urban Trees Exit (October 26, 2015) – Citizen scientists and researchers at the University of California, Riverside, are measuring which species of trees provide the most cooling benefits for the least amount of water.
  • Sonoma County Turns to Green, Living Roofs Exit (October 2, 2015) – A growing number of homeowners and businesses in Sonoma County, California, are installing green roofs.
• September 2015
  • University of Wisconsin Researchers Examine Impact of Extreme Heat Events on Urban Heat Islands Exit (September 28, 2015) – University of Wisconsin-Madison researchers discovered that urban areas in Madison experienced up to twice as many hours over 90 degrees Fahrenheit compared with rural areas during a 2012 heat wave.
  • University of Georgia Researchers Rank U.S. Cities Based on Urban Heat Island Impact Exit (September 16, 2015) – Researchers from the University of Georgia identified Salt Lake City, Miami, and Louisville as the three cities with the strongest urban heat island effects in the United States.
  • California EPA Develops Urban Heat Island Index Exit (September 16, 2015) – The California Environmental Protection Agency released a new Urban Heat Island Index designed to help state and local governments prioritize areas for heat island mitigation.
• August 2015
  • NASA Study Finds Important Influence of Vegetation Type on Heat Island Effect Exit (August 25, 2015) – A NASA study has found that the type and extent of vegetation in a city’s surrounding environment has a “commanding” influence on the urban heat island effect. Cities that are surrounded by forests tend to have strong heat islands, while cities in arid lands may be cooler than their surroundings. The study also found that smaller cities generate less heat.
  • New York and New Jersey Port Authority Building Shows Temperature Benefit of Green Roof Exit (August 13, 2015) – A New York and New Jersey Port Authority building released infrared images of the temperature difference between its green roof and surrounding paved areas.
• July 2015
  • Chicago Botanic Garden Completes Green Roof Study Exit (July 21, 2015) – The Chicago Botanic Garden announced the results of the largest green roof study conducted to date in the United States, which evaluated more than 200 species in Chicago’s climate zone (Zone 5) over five years. The study identified nine plants as the best to incorporate into green roofs in Zone 5.
  • St. Elizabeth Hospital in Minneapolis, MN Installs 6,110 Square-Foot Green Roof Exit (July 17, 2015) – The St. Elizabeth Hospital in Minneapolis, Minnesota completed installation of a 6,110 square-foot green roof.
  • Weather.com Ranks U.S. Cities Affected by Climate Impacts Exit (July 14, 2015) – Weather.com created a ranking of U.S. cities affected by climate impacts, factoring in urban heat island effect, precipitation, drought, sea level rise, and other metrics. The ranking finds that New Orleans, Louisiana; Minneapolis, Minnesota; and Las Vegas, Nevada are the three most vulnerable cities.
  • University of Chicago Researchers: Urban Trees Can Improve Health Exit (July 9, 2015) – Researchers from the University of Chicago found that having 10 more trees in a city block, on average, improves health perception in ways comparable to that from an increase in annual personal income of $10,000, moving to a neighborhood with $10,000 higher median income, or being 7 years younger.