Book contents
- Frontmatter
- Contents
- List of Figures and Tables
- Acknowledgments
- Introduction
- PART ONE EARTH'S CLIMATE HISTORY AND OUTLOOK
- 1 Salient Events of Climate History
- 2 Human and Climate Interactions
- 3 Greenhouse Gases
- 4 Emitting Economic Sectors
- 5 Forecasts of GHG Emissions and Global Temperatures
- 6 Potential Impacts of Climate Change
- PART TWO CLIMATE POLICY CHOICES
- Appendix: Discount Rates in Climate Analysis
- References
- Index
5 - Forecasts of GHG Emissions and Global Temperatures
Published online by Cambridge University Press: 01 June 2011
- Frontmatter
- Contents
- List of Figures and Tables
- Acknowledgments
- Introduction
- PART ONE EARTH'S CLIMATE HISTORY AND OUTLOOK
- 1 Salient Events of Climate History
- 2 Human and Climate Interactions
- 3 Greenhouse Gases
- 4 Emitting Economic Sectors
- 5 Forecasts of GHG Emissions and Global Temperatures
- 6 Potential Impacts of Climate Change
- PART TWO CLIMATE POLICY CHOICES
- Appendix: Discount Rates in Climate Analysis
- References
- Index
Summary
The planet's temperature has been rising over the last century in large part, evidently, because of anthropogenic emissions of greenhouse gas (GHG). The prospects for future emissions depend on a host of variables, including population growth, economic development, technological advances, and the efforts and policies that will be undertaken to mitigate climate change. The consequences for the atmospheric concentrations of GHG and the global average temperatures depend on the responses of various natural mechanisms, including both amplifying and restraining feedbacks. Potential tipping points in the climate system are a major concern. It is difficult to assess the likely outlook for emissions and temperature change. Weighing the uncertainties surrounding possible outcomes is an even more daunting task, but an essential one.
BUSINESS-AS-USUAL TRENDS
Anthropogenic emissions of GHGs may have affected Earth's climate as early as the invention of agriculture; in any case, they are surely a key to future climate change. A number of forecasters expect that under business-as-usual (BAU) assumptions, meaning no new mitigation policies, emissions will likely continue to grow for some time at rates similar to those observed over recent decades once the current economic recession has passed. The IPCC's measure of anthropogenic emissions of carbon dioxide (CO2)-equivalent GHG, which leaves out ozone, ozone-depleting substances, and aerosols, grew an average 1.5% per year between 1970 and 2004. Stern (2006) projected a continuation of that trend growth through 2050 under BAU policies.
- Type
- Chapter
- Information
- Climate Policy FoundationsScience and Economics with Lessons from Monetary Regulation, pp. 82 - 95Publisher: Cambridge University PressPrint publication year: 2011