STEVE EMBER: I'm Steve Ember.

SHIRLEY GRIFFITH: And I'm Shirley Griffith with EXPLORATIONS in VOA Special English. Today we explore ways in which local governments around the world are working to protect the environment.

These "green cities" are working to reduce energy use and pollution in inventive and effective ways. Such efforts by city governments not only help reverse the effects of climate change. They also help governments save large amounts of money on energy costs. And, cities that are leaders in this green movement set a good example to their citizens about the importance of environmental issues.

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STEVE EMBER: The Kyoto Protocol is an international agreement aimed at reducing the release of harmful gases believed to cause climate change. The United States is not part of the agreement. But since two thousand five, more than one thousand mayors across the country have agreed to sign their own version of the protocol.

It is called the United States Conference of Mayors' Climate Protection Agreement. Local leaders have agreed to follow the suggestions of the Kyoto Protocol in their communities. They have also agreed to urge state and federal governments to follow these suggestions. One goal is to reduce air pollution to nineteen ninety levels by two thousand twelve.

A "green" city might work on several kinds of environmental goals and programs. These include air quality, reducing electricity use, green building, public health, the reuse of materials, water quality and clean transportation.

SHIRLEY GRIFFITH: The Natural Resources Defense Council works to protect the environment through activism, law and science. One of its online projects is called Smarter Cities. This web site gives a list of cities that have made important environmental steps. Its two thousand ten list includes twenty-two cities that have supported investing in green power and reducing energy use. The list is divided into large, medium and small cities.

STEVE EMBER: Boston, Massachusetts was second on the big city list. It is the largest city buyer of wind power in New England. It is also using its own wind resources to produce electricity. There are twenty small wind turbines at Logan International Airport. And there are other wind projects around the city.

SHIRLEY GRIFFITH: Austin, Texas leads the large city list, while Chicago, Illinois is third. Both cities have made big efforts to reduce a problem called urban heat islands. An urban heat island is a city area that is warmer than its surrounding rural area. This is caused by several things, such as dark colored roofs which absorb heat from the sun during the daytime, and release that heat at night. Air conditioners cooling the inside of buildings add to the increased temperatures by generating hot air outdoors.

Austin has launched an Urban Heat Island Mitigation Project to improve the situation. The city is planting more trees. And it is rewarding businesses and individuals who have reflective roofs. This kind of surface absorbs less heat.

STEVE EMBER: Chicago has long been interested in green roofs. In two thousand, city officials decided to replace the black tar roof on the city government building with a planted garden. The aim was to reduce energy costs, improve air quality and control the amount of rainwater entering the city's waste system. Green roofs also help reduce urban heat islands.

During hot weather, the building's tar roof could reach temperatures of up to seventy-six degrees Celsius.

With the garden, the temperature of the roof area was reduced by at least thirty degrees Celsius. Chicago has since created over three hundred thousand square meters of green roofs.

SHIRLEY GRIFFITH: Washington, D.C. is also a leading city for green roofs, with over ninety two thousand square meters of green rooftops. The city also launched a program called "Skip the Bag, Save the River." Stores charge people a five cent tax for using plastic or paper shopping bags instead of reusable bags. Money from the tax will be used to clean up a local river.

New York City is using water as a renewable energy source. For several years, the city has experimented with using waves in the East River to create energy. Officials operating the program recently asked for permission to put into place thirty river turbine devices.

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STEVE EMBER: The people of Portland, Oregon are among the top recyclers in the nation. People living there recycle over half of the waste they throw out. The city has also worked to provide green transportation by providing safe bike paths and free parking spaces where electric cars can recharge.

In Oakland, California, you can ride on one of several public hydrogen-powered buses. These buses release zero pollution into the air. However, they cost about five times more than common buses.

SHIRLEY GRIFFITH: Cost is also a major issue in creating green buildings and systems. Green building materials and systems usually cost more money than normal ones. However, homeowners are increasingly willing to pay more money to have lower energy costs in the future. And, builders are offering more green building methods and products as they become more important to buyers.

Many cities offer money for homeowners who put in place green technologies such as solar power systems. This helps support green efforts by reducing the cost to homeowners.

Investors are also taking a big interest in the growing importance of clean technologies. The Cleantech Group researches the clean energy industry. It said that North American companies in two thousand ten raised over five billion dollars for investment in clean technologies. This is an increase of forty-five percent from two thousand nine.

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STEVE EMBER: The United States Green Building Council is changing the way people build in cities. This nonprofit organization has a rating system for making environmentally safe public and private buildings. It is called Leadership in Energy and Environmental Design, or LEED. Many cities now require that new buildings be built according to LEED environmental requirements.

LEED is not the only rating system for green buildings. For example, the National Association of Homebuilders has its own set of rules. And, the United States Environmental Protection Agency and Department of Energy joined to create the Energy Star program.

SHIRLEY GRIFFITH: Energy Star gives ratings to devices for the home based on how they use energy. And the program helps homeowners learn how to make changes to their houses to use energy effectively. Energy Star estimates that in two thousand nine it helped Americans avoid the release of harmful gases equal to what thirty million cars would produce. And, it says Americans saved seventeen billion dollars on energy costs.

STEVE EMBER: One small town in Kansas is about as green as its name. In May of two thousand seven, a tornado windstorm destroyed most of the town of Greensburg, Kansas. The town decided to rebuild in a better way, using green methods.

Greensburg officials decided that all public building projects would follow LEED top-level requirements. For example, the 5.4.7. Arts Center is completely powered by energy from the wind and sun. It was named after the date the tornado struck. The television station Planet Green aired a program on the town called "Greensburg." Over three seasons, the show told about the town, its people, and the green building efforts.

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SHIRLEY GRIFFITH: The United Arab Emirates has taken green building a step further with the Masdar City project. Its aim is to be the greenest city in the world. The city will meet environmental rules set by the World Wide Fund for Nature's One Living Planet and the company BioRegional. Masdar City is about seventeen kilometers from the capital, Abu Dhabi. The goal for Masdar City was to produce no waste, no carbon pollution and contain only electric cars. The city is to create renewable energy from the wind, sun and other technologies.

However, economic troubles have slowed the project. The city was expected to be completed by twenty sixteen. But officials now say the city will be completed in stages. And, the city will not at first be completely carbon-neutral.

One important part of the city is Masdar Institute. This research university is being developed in partnership with the Massachusetts Institute of Technology in Cambridge, Massachusetts. The goal of the university is to make the United Arab Emirates a leader in renewable energy technologies. Experts say developments like this may lead to a greener future for all cities in the world.

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STEVE EMBER: This program was written and produced by Dana Demange. I'm Steve Ember.

SHIRLEY GRIFFITH: And I'm Shirley Griffith. Join us again next week for EXPLORATIONS in VOA Special English.

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