|
|
|
| Temporal and Spatial Characteristics of Gale Weather over Northwest China |
| LI Yao-hui1,2, ZHANG Cun-jie1, GAO Xue-jie3 |
1. Key Laboratory of Arid Climatic Changing and Reducing Disaster of Gansu Province, Institute of Arid Meteorology, China Meteorological Administration, Lanzhou 730020, China;
2. Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China;
3. National Climate Center, Beijing 100081, China |
|
|
|
|
Abstract The temporal and spatial characteristics of gale and the relationships between gale weather and sand-dust storm over northwest China are analyzed in detail by using the gale and sand-dust storm data for the period from 1960 to 2000 of 127 observational stations which are proportionally located in northwest China and west part of the Inner Mongolia. Some significant results and new facts are obtained. It can be divided into four sub-regions according to the annual frequency of gale weather in northwest China, which are fewer gale region(where annual gale weather are less than 10 days), more gale region(where annual gale weather are between 10 to 50 days), much more gale region(where annual gale weather are between 50 to 100 days) and frequent region(where annual gale weather are more than 100 days). Most parts of northwest China are more gale regions, and the most frequent region of gale weather is the Ala Mountain pass of northwest Xinjiang which yearly gale weather are more than 160 days. Yanan in Shanxi province is the region where gale weather is the least in northwest China, which the annual gale weather is less than 1 day. It has close relationship between gale spatial distribution and terrain that gorges, mountains and Qinghai-Xizang Plateau have more gale weathers than other areas. The reducing trend of gale is clear in most regions of northwest China in recent 40 years, whereas the gale increasing region mainly locates from northeast part of Xinjiang to west part of Qinghai, where the annual gale days of representative station in 1980s were 190 days, three times more than 1960s. In general, gale weather in northwest China occurs mostly in spring, especially in May, and the least is in autumn. There are more summer gale weathers in middle-south parts of Shanxi and Gansu provinces. Southeast part of Qinghai has more winter gale.Further investigations show that, some gale frequent regions are not completely the same as the sand-dust storm regions. But in recent 40 years, the trend of temporal variation of gale is consistent with sand-dust storm in northwest China, all which shows the same time feature of linear decreasing. Therefore, under such a fact that the landuse over northwest China do not or will not change better now or latter, the decreasing of gale weather may be the only and real reason to reduce sand-dust storm here.
|
|
Received: 17 November 2003
Published: 20 December 2004
|
|
|
| No Suggested Reading articles found! |
|
|
Viewed |
|
|
|
Full text
|
|
|
|
|
Abstract
|
|
|
|
|
Cited |
|
|
|
|
| |
Shared |
|
|
|
|
| |
Discussed |
|
|
|
|
2004, Vol. 24 
