Book contents
- Frontmatter
- Contents
- Preface
- 1 Introduction
- Part I The Earth System
- Part II Global Physical Climatology
- 4 Atmospheric radiation
- 5 Atmospheric general circulation and climate
- 6 Earth's climates
- 7 Climate variability
- 8 Climate change
- Part III Soil Processes
- Part IV Hydrometeorology
- Part V Biometeorology
- Part VI Terrestrial Plant Ecology
- Part VII Terrestrial Forcings and Feedbacks
- Index
- Plate section
- References
8 - Climate change
from Part II - Global Physical Climatology
- Frontmatter
- Contents
- Preface
- 1 Introduction
- Part I The Earth System
- Part II Global Physical Climatology
- 4 Atmospheric radiation
- 5 Atmospheric general circulation and climate
- 6 Earth's climates
- 7 Climate variability
- 8 Climate change
- Part III Soil Processes
- Part IV Hydrometeorology
- Part V Biometeorology
- Part VI Terrestrial Plant Ecology
- Part VII Terrestrial Forcings and Feedbacks
- Index
- Plate section
- References
Summary
Chapter summary
Climate has changed over the course of Earth's history and will change in the future. Just 18 000 years ago, Earth was in the grips of a prolonged cold period in which vast tracts of the Northern Hemisphere were covered with ice. Over the past two million years there have been numerous such ice ages separated by shorter, warm interglacial periods. Our current climate is that of a warm interglacial and history suggests that over the next several thousand years prolonged cooling culminating in another ice age is possible in the absence of human influences. The geologic record also reveals numerous rapid climate changes over periods as short as decades or centuries. Climate change is the result of changes in the external forcing of the climate system by the Sun and internal physical, chemical, and biological feedbacks among the atmospheric, oceanic, and terrestrial components of the climate system. Plate tectonics and changes in the geometry of Earth's orbit around the Sun influence climate at timescales of millennia or longer. Changes in the concentration of greenhouse gases or in the runoff of freshwater to oceans affect climate at timescales of centuries to millennia. Changes in solar irradiance or volcanic eruptions that emit aerosols into the atmosphere influence climate at timescales of years to decades. Climate change over the twentieth century is reviewed in the context of greenhouse gases and anthropogenic influences on climate.
- Type
- Chapter
- Information
- Ecological ClimatologyConcepts and Applications, pp. 105 - 128Publisher: Cambridge University PressPrint publication year: 2008