For the UN Secretary-General, the benefits of making cities more environmentally friendly are "enormous", and include reduced climate risk, more jobs, and better health and well-being. "City leadership in using green materials and constructing energy-efficient, resilient buildings powered by renewable energy, is essential to achieve net-zero emissions by 2050," said António Guterres in his message for World Habitat Day, marked on Monday. The theme for this year's celebration of cities and towns worldwide is Accelerating urban action for a carbon-free world. Cities are responsible for about 75 percent of the world's energy consumption and over 70 percent of global greenhouse gas emissions. Urban areas across the globe are facing the dual crises of COVID-19 and climate change, said the UN chief. Around 4.5 billion people live in cities today, but that population is projected to grow by almost 50 percent, by 2050. By mid-century, over 1.6 billion urban residents may have to survive through average summertime highs of 35 degrees Celsius. For Guterres, cities and towns are at the core of climate action to keep the 1.5 degrees goal within reach. "Three-quarters of the infrastructure that will exist in 2050 has yet to be built," he said. "Economic recovery plans offer a generational opportunity to put climate action, renewable energy, and sustainable development at the heart of cities' strategies and policies." As populations grow in emerging economies, demand for transport, which accounts for nearly 20 per cent of global carbon emissions, is also multiplying. The UN Chief said cities are already working on this, trying to ensure that this demand is met by zero-emission vehicles and public transit. Guterres concluded asking for a global moratorium on internal combustion engines to underpin these efforts, saying it should happen by 2040 at the latest. In a message for the day, Executive Director of UN-Habitat, Maimunah Mohd Sharif, said that, unless the world takes urgent action, "the greenhouse gases produced by ever expanding urban centres, will continue to push global air temperatures higher." Sharif remembered that, this year, the day is celebrated only weeks before the UN climate change summit, COP26, happening in early November in Glasgow. For the UN-Habitat Chief, the recovery from the COVID-19 pandemic is an opportunity for the world's cities to put climate action on top of their agenda. "This is a chance to change how we generate our power, construct our buildings, heat, cool and light up our offices and homes, and travel around from home to work," she said. Sharif asked for "well planned and well managed compact cities", that allow for non-motorized transport and that reduce energy consumption from cooling and heating. "Cities are the incubators of innovation and new technology," she said. "We must harness this strength for better climate change solutions." For Sharif, "action will differ from city to city", but "the green transition must benefit everyone, especially the most vulnerable, and create new jobs." Activities Events this year will explore how governments and organizations can work together with communities, academic institutions and the private sector to create sustainable, carbon-neutral, inclusive cities and towns. World Habitat Day will also amplify the Race to Zero Campaign and encourage local governments to develop actionable zero-carbon plans in the run up to the COP26. On Monday, in a ceremony in Yaounde, Cameroon, UN-Habitat will also present the winners of the Scroll of Honour awards, one of the world's most prestigious prizes for those working on sustainable urbanization. This year, there are five winners: New Urban Communities Authority, from Egypt; Shining Hope for Communities, from Kenya; Baoji City, from China; Let's do it World, from Estonia; and Ciudad Emergente, from Chile. -- UN News