Study Note 1. Global environmental problems facing the world today: selected sources of information

By Masa Nagai, updated 8 August 2025

World has been constantly changing and evolving. In parallel, the environment across the planet has been changing dramatically because of human impact. Human-induced environmental changes then affect all of us on Earth.

By the mid 20th century, pollution started to become a social issue affecting human health and the environment in industrialized countries. It was then considered mainly a local problem within the limited area of a country, and often neglected behind the primacy of economic development. In the mid 1960s, transboundary air pollution, which caused acid rain and damaged forests and lakes in Europe, surfaced as an international concern and triggered an initiative to bring “the question of human environment” into the United Nations for policy consideration, subsequently leading to the United Nations Conference on Human Environment (Stockholm, Sweden, June 1972). The Stockholm Conference set “the environment” as a global agenda for action, and laid the foundation of international institutional frameworks in the field of the environment, including the United Nations Environment Programme (UNEP).

In the ensuing years, a growing number of environmental problems have been identified progressively over the course of the past half a century. Collaborative efforts of scientists and experts around the world, often coordinated by the processes managed by UNEP and other international organizations, led to better understanding of emerging global environmental changes caused by certain human activities, such as the depletion of the ozone layer, climate change, loss of biodiversity, land degradation and desertification, and global pollution of hazardous chemicals.  Plastic pollution was added to the list of those global environmental problems recently.

In order for an environmental problem to be recognized as an international concern and become a global policy issue, it normally follows a process in which scientific evidence and its findings are formally recognized by institutions with public authority, such as intergovernmental bodies (e.g. United Nations Environment Assembly of UNEP). For that purpose, science-based knowledge needs to be translated into “policy-relevant” information normally presented in a report, so that policymakers can consider and take decisions on how to act on those global environmental problems.

The selected sources of information concerning the state of the global environment or thematic environmental issues are listed below. Those listed are prepared by the organizations as indicated below, respectively. It should be noted that there are a large number of reports on relevant global environmental issues published by many different entities. The present note therefore highlights the selected major reports on the relevant subjects only.

Selected sources of information