### Environment Beyond a Century of Climate Change - Survival Crisis at the Beginning of the 21st Century

### Environment Beyond a Century of Climate Change - Survival Crisis at the Beginning of the 21st Century

In a future where temperatures will rise three to four degrees Celsius, human survival will require massive migration and urban construction. Vast tracts of land in the tropics will have to be abandoned, and we will have no choice but to rely on new forms of agriculture. These arguments rapidly became a reality from the end of the 20th century to the beginning of the 21st century, and they strongly reflect the historical background in which climate change was already steadily progressing. The Kyoto Protocol of 1997 was an important attempt to set up a framework for greenhouse gas reductions, but its withdrawal by the United States and the increase in emissions from emerging countries made it less effective, and the goal of a temperature rise of no more than 2 degrees Celsius was shaky, with a more serious future of 3 to 4 degrees Celsius rise at the center of discussion.

During the same period, extreme weather events were hitting many parts of the world, with heat waves claiming tens of thousands of lives in India and Pakistan, and droughts spreading hunger and migration in the Sahel region of Africa. Climate change is now recognized not only as an environmental problem, but also as a "survival crisis" that threatens the stability of nations and the international order. The concept of "climate refugees" spread throughout the international community, and a vision of a future in which the migration of hundreds of millions of people was inevitable was drawn up. Canada and Scandinavia, which are located in high latitudes, attracted attention as migration destinations, and the idea of planned large-scale migration became a reality against the backdrop of post-Cold War urban engineering and globalization.

Fundamental changes were also required in agriculture. Conventional methods were unable to cope with climate change, and advances were made in the development of drought- and cold-resistant crops through genetic modification, as well as irrigation technology and water circulation systems to improve the efficiency of water resources. Furthermore, precision agriculture using sensors and drones, and smart agriculture that controls temperature and humidity have emerged, and food supply has become a survival strategy tied to science and technology. Urban planning envisioned infrastructure based on stilted roads, wetland preservation, and renewable energy, and the possibility of hydroelectric power generation from melting glaciers also attracted attention. These technologies became the means by which humanity could survive the harsh climate, and a new framework for living in harmony with the environment was called for.

Thus, the issues of climate change and the crisis of survival are taking shape in the context of the stagnation of international politics, the worsening of regional disasters, and the progress of technological innovation at the beginning of the 21st century, and continue to force humankind to make choices that go beyond conventional social structures.