With a global urban environment summit less than 50 days away, the Gwangju metropolitan government is gearing up to host the southwestern city's biggest international gathering to date, organizers said Wednesday. The 2011 Gwangju Summit of the Urban Environmental Accords (UEA) will be held in Gwangju, about 330 kilometers southwest of Seoul from Oct. 11-13 and is expected to bring together mayors, scholars and activists from nearly 90 cities across the globe. The summit is hosted by the local government, the United Nations Environment Program (UNEP) and the U.S. city of San Francisco. Signed in June 2005 by mayors from 52 cities to celebrate the World Environment Day, the UEA has emerged as a hallmark of urban leadership's efforts to address the wide range of environmental issues facing cities. With a pre-registration rate for participation in the event reaching 50 percent, the summit is expected to become the single biggest international event that the local municipal government has ever held, Gwangju municipal government officials said. A total of 86 cities, including Curitiba, Brazil and Auckland, New Zealand, have registered for the event as of Sunday, adding to hopes that the summit will attract a record number of foreign officials and mayors. The three-day summit will cover two major topics: developing a system to evaluate environmental policies and trying to revive a previous effort to set up an emissions trading framework. Summit attendees will try to develop a practical and universal index to evaluate cities' eco-friendly policies. The existing standards are either outdated or do not consider the differences between developed and developing countries. The other goal for the summit is to set up a framework for the Clean Development Mechanism (CDM) as part of global efforts to reduce greenhouse gas emissions. A joint study with the UNEP has been under way since 2007. The CDM was created under the Kyoto Protocol as one of several ways to facilitate carbon trading in an effort to get cities to cut greenhouse gas emissions. The 1997 protocol obliges nearly 40 developed countries to reduce their emissions over a five-year period through the end of 2012 by an average of 5.2 percent from 1990 levels. But the CDM has not led to a functional carbon trading system, and so summit attendees hope to discuss the agreement and hammer out a new framework for emissions trading. Organizers, meanwhile, said they have finalized the panel of keynote speakers, which include the heads of the two largest environmental institutions -- Achim Steiner, executive director of the UNEP, and Joan Clos, executive director of U.N.-Habitat, a U.N. agency that addresses human settlement issues and pursues providing adequate shelter for all people. A handful of well-known officials and activists are also slated to discuss environmental issues at symposiums and forums that will take place on the sidelines of the summit. Speakers include Earth Policy Institute President Lester Brown and Indian environmental activist Vandana Shiva. The Gwangju regional government is in the final stages of fine-tuning summit venues, security measures and detailed schedules, the officials said.