LONDON, March 27 (UPI) -- Humanity's urban footprint on Earth will expand by an area equal to France, Germany and Spain combined in less than 20 years, researchers say.
That ongoing pattern of urban sprawl puts humanity at severe risk due of environmental problems, scientists at the "Planet Under Pressure" scientific conference in London were told, but "options and opportunities" are possible, researchers said.
Reforms in existing cities and better planning of new ones offer disproportionately large environmental benefits compared with other options, Shobhakar Dhakal of the Tokyo-based Global Carbon Project told the conference attendees.
"Re-engineering cities is urgently needed for global sustainability," Dhakal, said, noting emerging urban areas "have a latecomer's advantage in terms of knowledge, sustainability thinking, and technology to better manage such fundamentals as trash and transportation."
"Our focus should be on enhancing the quality of urbanization -- from urban space, infrastructure, form and function, to lifestyle, energy choices and efficiency."
Failure to do so risks unwelcome potential problems of dense urbanization including congestion, pollution, crime, the rapid spread of infectious disease and other societal problems, he said.
Other researchers agreed.
"The way cities have grown since World War II is neither socially or environmentally sustainable and the environmental cost of ongoing urban sprawl is too great to continue," Karen Seto of Yale University said.
