WRI's experts  will continue to provide commentary and analysis of the results of the Rio+20 conference  through our series, "Rio+20 in the Rear View." For more posts in this series, see here  and here .
During the informal sessions of the U.N.’s Rio+20 conference  on sustainable development last week, Rio de Janeiro city officials and the World Bank jointly launched a very timely project: the Rio Low-Carbon City Program . Under this initiative, the city will introduce low-carbon strategies like bus rapid transit (BRT) corridors , upgraded urban rail systems, bikeways, and an integrated solid waste management system in order to significantly reduce its greenhouse gas (GHG) emissions.
The program came about due to the city’s landmark 2011 municipal climate change law, which requires Rio to avoid 20 percent of 2005 GHGs emissions by 2020. This cut will amount to a reduction of 2.27 million tons of carbon dioxide from the business-as-usual scenario.
Rio de Janeiro and the Greenhouse Gas Protocol
As a part of the announcement, Rio’s vice mayor, Carlos Alberto Muniz, released the results of the city’s 2005 GHG inventory, a measurement of the city’s total GHG emissions. The Greenhouse Gas Protocol (GHG Protocol) , led by the World Resources Institute , provided some very significant contributions to informing the development of Rio’s GHG inventory and determined some of the best mitigation opportunities. One year ago, WRI’s GHG Protocol team spent time in Rio providing technical assistance  to the local government and the Rio Federal University (COPPE) to complete the city’s base-year GHG inventory of its 2005 emissions. Together, the partners worked to develop a long-term GHG monitoring program—a necessity because Rio’s climate law mandates that the city update its GHG inventory every four years beginning in 2012.
Lessons from Rio
It’s exciting to see Rio joining the cadre of cities providing leadership in managing GHG emissions. During the launch event, Vice Mayor Muniz; Nelson Moreria Franco, head of Rio’s climate change office; and Emilio La Roverse, a professor at COPPE; talked about Rio’s GHG inventory and the city’s ambitious plan to reach its GHG reduction target by 2020. Four important points emerged from the discussion:
GHG inventory as the basis for low-carbon city strategies: Franco emphasized the important role the GHG inventory has, and will continue to play in helping Rio reduce its emissions—you can’t manage what you can’t measure. The inventory provided the base year emissions against which reductions can be measured, and it also identified the key sources of GHG emissions in Rio. The city found that the transport and waste sectors are the largest sources of emissions, contributing about 39 percent and 14 percent respectively of total city emissions. As a result, the city is developing a series of GHG mitigation strategies for these sectors, including a new bus rapid transit corridor , which was supported by EMBARQ , WRI’s Center for Sustainable Transport.
Accounting both direct and indirect GHG emissions: Rio’s 2005 GHG inventory was reported using the GHG Protocol’s “Scope” framework, which distinguishes between emission sources within the city boundary (Scope 1) and emissions due to city residents’ consumption and activities that occur at sources outside the city (Scope 2 and Scope 3). La Roverse emphasized that Rio’s inventory presents not only Scope 1 emissions, but also emissions from the generation of electricity (Scope 2) and the disposal of wastes outside the city boundary (Scope 3). Including a city’s scope 2 and 3 emissions can be difficult, but it’s crucial to ensuring that full emissions are documented.
Consistency with international best practices: La Roverse highlighted the fact that Rio’s inventory is consistent with the Global Protocol for Community-Scale GHG Emissions (Pilot Version)  that was recently released by C40 Cities Climate Leadership Group , ICLEI – Local Governments for Sustainability , and WRI. The Protocol provides a framework to help cities conduct their GHG inventories in a consistent and comprehensive manner. Compatibility with the Global Protocol can facilitate cross-learning between cities. He cited an example: “If both Rio and New York City are using the Global Protocol, we can easily compare our inventory results and GHG performance with them and learn successful best practices.”
Institutionalizing the long-term GHG monitoring program: Vice Mayor Muniz announced that Rio will start its long-term GHG monitoring program in 2012 to ensure regular updating of its GHG inventory. In addition to the inventory compilation team, there will be an independent review team and a verification team for quality assurance. This city-level program is the first of its kind in the southern hemisphere, and Muniz expressed excitement to share their experience with other cities.
Although concrete results are yet to be seen, Rio has taken bold steps to drive GHG reductions in the city. It gives a good example for other cities to look at while conducting their GHG inventories and developing their own low-carbon initiatives.
Check out more information  about GHG Protocol’s city work. Cities interested to participate in the pilot program for the draft Global Protocol may contact Wee Kean Fong at WFong@wri.org.