tailieunhanh - CLIMATE CHANGE SCIENCE AN ANALYSIS OF SOME KEY QUESTIONS

Greenhouse gases are accumulating in Earth’s atmosphere as a result of human activities, causing surface air temperatures and subsurface ocean temperatures to rise. Temperatures are, in fact, rising. The changes observed over the last several decades are likely mostly due to human activities, but we cannot rule out that some significant part of these changes is also a reflection of natural variability. Human-induced warming and associated sea level rises are expected to continue through the 21st century. Secondary effects are suggested by computer model simulations and basic physical reasoning. These include increases in rainfall rates and increased susceptibility of semi-arid regions to drought. The impacts of these changes will be critically dependent on. | Climate Change Science an analysis of some key questions NATIONAL RESEARCH COUNCIL Climate Change Science an analysis of some key questions Committee on the Science of Climate Change Division on Earth and Life Studies National Research Council N ATIONAL ACADEMY PRESS W ashington . NATIONAL ACADEMY PRESS 2101 Constitution Avenue . Washington . 20418 NOTICE The project that is the subject of this report was approved by the Governing Board of the National Research Council whose members are drawn from the councils of the National Academy of Sciences the National Academy of Engineering and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competences and with regard for appropriate balance. International Standard Book Number 0-309-07574-2 Additional copies of this report are available from National Academy Press 2101 Constitution Avenue . Lockbox 285 Washington . 20055 800 624-6242 202 334-3313 in the Washington metropolitan area http Printed in the United States of America Copyright 2001 by the National Academy of Sciences. All rights .