Chapter Four

The Consequences of Global Change

"...systems such as the atmosphere or the oceans - that we once thought were too big to be affected by human activity - are beginning to show the strain of 5.3 billion people consuming raw resources, emitting chemical by-products and disposing of unwanted waste. The strain is causing these global systems to change in ways that scientists do not fully understand." (Global Change and Canadians, p.19.)

Summary

This chapter examines some of the major global change issues. The chapter provides a brief summary of current knowledge about the causes, extent and likely consequences of these changes. The four major global systems considered are: the atmosphere, the land, fresh water and the oceans. While these systems are considered sequentially, it is important to remember that change in one system often affects the others.

Educational Significance

The Interconnectedness of earth systems. All Earth systems are interconnected and a change in one will result in changes in others. Scientists do not fully appreciate how these systems function and how they relate to each other.

Indications of change. Major systems such as oceans and the atmosphere, that we once thought too big to be affected by human activities, are beginning to show the strain of our collective impact.

Global change does not respect borders. Global changes affect globally-not nationally, provincially or municipally. Environmental issues resulting from these global changes will require global solutions.

Climate change is a subset of global change. Climate change is a very important component of global change, but by no means encompasses global change. Other issues such as ozone depletion, air pollution, soil degradation, loss of biodiversity and terrestrial habitat, and others fall outside climate change but are either directly or indirectly the result of human activities.

Learning Outcomes

Students will:
  • describe the major environmental systems affected by human activities;
  • identify and describe the ways in which human activities are affecting the air, the ocean, fresh water, and land;
  • explore current research findings concerning global change in the four Earth systems: air, oceans, land, and fresh water;
  • assess the possible consequences of changes to these major systems for humans; and
  • identify important areas of ignorance regarding the extent and rate of global changes and the possible consequences of these changes
TABLE OF CONTENTS | CHAPTER ONE: WHAT IS GLOBAL CHANGE? | CHAPTER TWO: WHY IS GLOBAL CHANGE IMPORTANT TO CANADA | CHAPTER THREE: THE CAUSES OF GLOBAL CHANGE | CHAPTER FOUR: THE CONSEQUENCES OF GLOBAL CHANGE | CHAPTER FIVE: HOW WILL GLOBAL CHANGE AFFECT SOCIETY? | CHAPTER SIX: CANADIAN RESPONSES TO GLOBAL CHANGE | APPENDIX | TABLE OF CONTENTS | CREDITS

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