| Services |
|
|
|
|
 |
|
| News |
|
|
|
|
|
|
|
|
|
| Channels |
| Home & Family |
|
|
|
|
|
|
|
| Leisure |
|
|
|
|
| Technology |
|
|
|
|
|
| Business |
|
|
|
|
| Science |
|
|
|
|
|
|
|
|
|
|
Site Search  |
|
|
|
|
| Free email |
|
|
|
|
 |
Detection of human influence on precipitation patterns |
| TheAllINeed.com |
(NC&T/UEA) Published in the science journal Nature on July 26, Detection of Human Influence On 20th-Century Precipitation Trends breaks new ground in climate change research.
The authors include leading climate scientists from around the world including Canada, the US, Japan and the UK. The UK authors are Peter Stott at the Met Office Hadley Centre and Nathan Gillett at the University of East Anglia.
The study demonstrates that human activities have contributed significantly to shifts in global precipitation patterns over the past century, including increased rain and snowfall in northern regions, drier conditions in tropical areas north of the equator, and increased rainfall in the southern tropics.
• The scientists studied the combined effect that changes in greenhouse gases and sulphate aerosol concentrations in the atmosphere have had on global precipitation over land during the past century. Greenhouse gases and sulphate aerosols are produced primarily by burning fossil fuels. Greenhouse gas concentrations in the atmosphere have increased steadily over the past century.
• Over the past century, climate records indicate there have been sizable shifts in precipitation patterns around the globe. Looking at average conditions over broad regions of the globe, and comparing them to changes anticipated due to human influence on climate, scientists have determined that human-induced climate change has caused most of the observed increase in precipitation north of 50° latitude, a region that includes Canada, Russia and Europe, as well as in the southern hemisphere. Human-induced climate change has also made important contributions to the drying observed in a broad region north of the equator that includes Mexico, Central America and northern Africa. These shifts may have already had significant effects on ecosystems, agriculture and human health, especially in regions that are sensitive to changes in precipitation, such as the Sahel region in northern Africa.
![]() • The evidence suggests that natural factors, such as volcanic activity, have also contributed to the changes in global precipitation patterns over the past century, although to a much smaller extent than human activity.
The study compared observed precipitation changes with those produced by complex computer climate models that were used to estimate the effects of human activities over the past century. In recent years, scientists have become increasingly sophisticated in combining different global climate models to increase the accuracy of their results. In this study, 14 different models were used. As a result, the scientists have considerable confidence in the findings of this study.
This study has also given scientists increased confidence in their ability to predict future changes in global climate. By using computer models to simulate climate change that has already occurred, the researchers have demonstrated the reliability of these models.
Human-induced changes have not previously been detected in global studies of precipitation, partly because drying in some regions cancels moistening in others, reducing the global signal. Here the scientists used the patterns of the changes in different latitude bands instead of the global average.
|
| About the Author |
©2006 All rights reserved
|
|
|
| Quotes | I will not expose the ignorance of the faculty. - Bart Simpson.
I want an Internet. Can I have one of those? -- Spice Girl Mel B.,aka Scary Spice, pointing to a monitor during an AOL press conference
I want to get a tatoo of myself on my entire body, only 2 taller. -- Steven Wright
I think you should defend to the death their right to march, and then go down and meet them with baseball bats.-Woody Allen, on the KKK
|
| Writers | | If you are a writer and want to see your article published at Theallineed.com, just click here to submit. |
|
Motivational techniques you can learn starting today