Urban Growth and Sustainable Cities
Urbanisation is happening everywhere, but it's absolutely exploding in poorer countries. Since 2007, more than half the world lives in cities - and that number keeps climbing. The main drivers are people fleeing rural poverty (called rural-urban migration) and higher birth rates in cities where young people have more babies.
Push factors force people out of rural areas - think natural disasters, war, drought, and lack of jobs. Pull factors draw them to cities with promises of better employment, healthcare, and education. Meanwhile, natural increase happens when birth rates exceed death rates, especially common in cities with lots of young adults.
A megacity has over 10 million people, and most are in developing countries like Brazil and Nigeria. By 2030, we'll have 41 megacities compared to just 28 today. These massive urban areas create both incredible opportunities and serious challenges.
Key insight: Two-thirds of current megacities are in poorer countries where urbanisation is happening fastest due to rapid economic growth.
Sustainable urban living means cities that don't trash the environment whilst ensuring future generations can thrive. Solutions include water conservation (rainwater collection, efficient toilets), energy conservation (renewable sources, efficient homes), waste recycling, and creating green spaces that provide cooling, exercise areas, and flood protection. Freiburg in Germany shows how it works - 40% forest coverage, integrated transport, and renewable energy making the city both liveable and environmentally friendly.
