Global Warming

• Main Author: North, Gerald R.
• Format: Other/Unknown Material
• Language: unknown
• Published: Wiley 2012
• Subjects: Ice; permafrost; Sea ice
• Online Access: http://dx.doi.org/10.1002/9780470057339.vag023.pub2; https://onlinelibrary.wiley.com/doi/pdf/10.1002/9780470057339.vag023.pub2; https://onlinelibrary.wiley.com/doi/full-xml/10.1002/9780470057339.vag023.pub2

Abstract Global warming refers to observation that the earth has been warming over the past century and the related theory that humans are responsible for the changes in global climate. The estimates of the warming are based on a global network of instrumental observations that the global average temperature of the planet has been increasing at an average rate of about 0.7 ± 0.2 °C per century over the last century. Indicators based upon paleoclimatic information stretching over the last several hundred thousand years suggest that this rate of warming is highly unusual, and not likely to be part of a pattern of natural variability internal to the system. Besides the temperature record, there are numerous other indicators of secular change in the planetary climate. A few of these include retreat of mountain glaciers, rise of sea level, melting of permafrost, reduction of sea ice, increases in heavy precipitation events, changes in growing season, as well as many others. The cause of such a warming is now rather well established. While we do not have complete enough information on all aspects of the climate system, we do have excellent coverage of a number of the relevant factors since the 1970s – the beginning of the satellite era. During this last few decades, we have not only accurate estimates of surface temperatures, but good observations of many aspects of the system including potential perturbing causes of change to the system such as the brightness of the sun and the concentrations of trace gases that can cause warming. In this article, the case will be made that the warming is real and that we have a good theory for why it is happening.