Abrupt Climate Change Inevitable Surprises (2002) / Chapter Skim
Currently Skimming:
1 Introduction to Abrupt Changes in the Earth's Climate
1 Introduction to Abrupt Changes in the Earth's Climate
Pages 10-18
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 10... ...
However, before the 1990s, the dominant view of past climate change emphasized the slow, gradual swings of the ice ages tied to features of the earth's orbit over tens of millennia or the 100-million-year changes occurring with continental drift. But unequivocal geologic evidence pieced together over the last few decades shows that climate can change abruptly, and this has forced a reexamination of climate instability and feedback processes (NRC, 1998~.Just as occasional floods punctuate the peace of river towns and occasional earthquakes shake usually quiet regions near active faults, abrupt changes punctuate the sweep of climate history.
|
From page 11... ...
Might human activities affect the possibility of recurrence? · To what extent is abruptness a fundamental characteristic of regional and global climate changes?
|
From page 12... ...
Here, we illustrate a few basic points using a mechanical analogy. Imagine a balance consisting of a curved track poised on a fulcrum, as shown above.
|
From page 13... ...
Plus, the recordings are badly scratched, so some of what was recorded is lost or garbled beyond recognition. If you can imagine this, you have some appreciation of the difficulties of paleoclimate research and of predicting the results of abrupt changes in the climate system.
|
From page 14... ...
For example, single floods, hurricanes, or volcanic eruptions are important for humans and ecosystems, but their effects generally would not be considered abrupt climate changes unless the climate system is pushed over a threshold into a new state; however, a rapid, persistent change in the number or strength of floods or hurricanes might be an abrupt climate change. The quintessential abrupt climate change was the end of the Younger Dryas interval about 11,500 years ago, when hemispheric to global climate shifted dramatically, in many regions by about one-third to one-half the difference between ice-age and modern conditions, with much of the change occurring over a few years (Alley, 2000~.
|
From page 15... ...
Climate changes synchronous with those in Greenland affected much of the world, as shown in Figures 2.1 and 2.3. ages and other features of deeper time and with studies of decadal-centennial climate modes and variability.
|
From page 16... ...
Recognizing the potential for abrupt changes in climate has constituted a paradigm shift for the research community, but many questions concerning the processes that cause and mediate abrupt climate change remain, including the following. · What are the patterns of environmental variability associated with abrupt climate change in the tropics and high latitudes?
|
From page 17... ...
For example, climatic conditions change greatly over short distances in some areas, and cause similarly steep gradients in vegetation types, allowing even a small climate change to cause dramatic change in vegetation type in a given locale. Rapid climate change will probably result in the redistribution and possibly in the extinctionof terrestrial and marine species and have major effects on ecosystems worldwide.
|
From page 18... ...
To help to focus priorities in abrupt climate change research, representatives of the economic and social science research communities were also part of the committee. Oversight for the committee was provided jointly by the Ocean Studies Board, the Polar Research Board, and the Board on Atmospheric Science and Climate.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.