This book focuses on the emergence of COVID-19 and climate change as twin mega risks to cities of both developed and developing countries. The work analyses how the pandemic has transformed city functions, promoted remote working, and affected socializing, education and learning patterns, recreation, as well as shopping and entertainment. It discusses the lessons learned from these two Mega Risks, the evolution of urban patterns and functions in their wake, and provides visionary thinking for the improvement of cities from the experiences gained. The COVID-19 Pandemic and climate change are both posing serious threats to cities' future. Together, they demand changes in the ways cities' function and operate. The work presents a case for a better understanding of the twin mega risks, the magnitude of their impacts, the responses of cities in combating these issues, and planning strategies for preparing, mitigating and adapting to these and future risks. The book is designed to provide reliable resource materials for a wide audience such as planners, professional practitioners, scientists, students, teachers and researchers working in various fields including geography, environmental sciences, social sciences, policy and planning.

Methane is an important greenhouse gas that can cause global warming. The present concentrations of methane are nearly three times higher than several hundred years ago. Today, more than 60% of the atmospheric methane comes from human activities, including rice agriculture, coal mining, natural gas usage, biomass burning, and raising of cattle. Methane affects the stratospheric ozone layer and the oxidizing capacity of the atmosphere, which in turn control the concentrations of many man-made and natural gases in the atmosphere. This book brings together our knowledge of the trends and the causes behind the increased levels of methane. Based on the scientific information on the sources and sinks, and the role of methane in global warming, strategies to limit emissions can be designed as part of a program to control future global warming.

Methane is an important greenhouse gas that can cause global warming. The present concentrations of methane are nearly three times higher than several hundred years ago. Today, more than 60% of the atmospheric methane comes from human activities, including rice agriculture, coal mining, natural gas usage, biomass burning, and raising of cattle. Methane affects the stratospheric ozone layer and the oxidizing capacity of the atmosphere, which in turn control the concentrations of many man-made and natural gases in the atmosphere. This book brings together our knowledge of the trends and the causes behind the increased levels of methane. Based on the scientific information on the sources and sinks, and the role of methane in global warming, strategies to limit emissions can be designed as part of a program to control future global warming.