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Temperature and Precipitation Trends in Minqin Desertduring the Period of 19612007

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Temperature and Precipitation Trends in Minqin Desertduring the Period of 19612007 Journal of Arid Land Volume 3 Issue 3 Article 8 9-7-2011 Temperature and precipitation trends in Minqin Desertduring the period of 19612007 ShuJuan ZHU 1 Gansu Minqin National Field Observation & Research Station on Ecosystem of Desertified Rangeland, Minqin 733300, China; 2 Key Laboratory of Desertification Combating of Gansu Province, Lanzhou 733070, China; 3 Gansu Desert Control Research Institute, Lanzhou 733070, China ZhaoFeng CHANG 1 Gansu Minqin National Field Observation & Research Station on Ecosystem of Desertified Rangeland, Minqin 733300, China; 2 Key Laboratory of Desertification Combating of Gansu Province, Lanzhou 733070, China; 3 Gansu Desert Control Research Institute, Lanzhou 733070, China, [email protected] Follow this and additional works at: https://egijournals.researchcommons.org/journal-of-arid-land Part of the Climate Commons Recommended Citation ZHU, ShuJuan and CHANG, ZhaoFeng (2011) "Temperature and precipitation trends in Minqin Desertduring the period of 19612007," Journal of Arid Land: Vol. 3 : Iss. 3 , Article 8. DOI: 10.3724/SP.J.1227.2011.00214 Available at: https://egijournals.researchcommons.org/journal-of-arid-land/vol3/iss3/8 This Research Article is brought to you for free and open access by Journals of EGI. It has been accepted for inclusion in Journal of Arid Land by an authorized editor of Journals of EGI. For more information, please contact [email protected]. Temperature and precipitation trends in Minqin Desertduring the period of 19612007 Cover Page Footnote This work is supported by “The 10th Five-year-plan” National Key Initiative Project (2002BA517A-09). This research article is available in Journal of Arid Land: https://egijournals.researchcommons.org/journal-of-arid- land/vol3/iss3/8 Journal of Arid Land 2011, 3(3): 214−219 doi: 10.3724/SP.J.1227.2011.00214 Science Press jal.xjegi.com; www.chiansciencejournal.com Temperature and precipitation trends in Minqin Desert during the period of 1961−2007 ShuJuan ZHU1,2,3, ZhaoFeng CHANG1,2,3∗ 1 Gansu Minqin National Field Observation & Research Station on Ecosystem of Desertified Rangeland, Minqin 733300, China; 2 Key Laboratory of Desertification Combating of Gansu Province, Lanzhou 733070, China; 3 Gansu Desert Control Research Institute, Lanzhou 733070, China Abstract: This paper analyzed the data of temperature and precipitation in Minqin, typical desert area in north- west China, during the period of 1961−2007 by linear regression. The result indicated that the increasing rate of the mean annual temperature in Minqin was higher than that of the average of China; and the temperature in February increased by 3.01ºC averagely in the past 47 years. The climate in Minqin displayed an evident warming trend. However, there was no evidently increasing trend of precipitation in the past 47 years, and drought occurred during the whole growing season. Keywords: temperature; precipitation; global climate; Minqin Global warming is now a hot topic worldwide. The 3rd autonomous region was in consistence with the evaluation report by IPCC (Intergovernmental Panel warming of northern hemisphere. Since the 1980s, the on Climate Change) indicated that the average tem- climatic variation in Xinjiang was consistent with the perature in the world rose by (0.6±0.2)ºC in the 20th climate warming in China and in the world (Liu et al., century, and the 1980s and 1990s were the warmest 2004; Qin et al., 2007), however, there were remark- years in this century (Gao et al., 2002). In the past able variations in different seasons and regions. The decades, 125 lakes around the Arctic disappeared due temperature rising rate in northern Xinjiang was ap- to global warming. By 2100, “the most possible mag- parently higher than that in southern Xinjiang (Cao et nitude” of temperature to rise globally will be 1.8−4ºC, al., 2011). In northern Xinjiang and Tianshan Moun- and the sea level will rise by 18–59 cm (Yang, 2007). tains, the average temperatures in recent 10 years were The latest IPCC report said that the temperature in 0.7ºC and 0.4ºC, respectively, which were higher than the average in the past 30 years (Ding et al., 2002). In northern hemisphere has risen by 0.4−0.8ºC averagely the recent 50 years, the temperature in the arid areas in from 1860 till now, and the temperature rise of the 20th northwest China displayed a rising trend (0.22ºC/10a) century is most marked in the millennium, and the (Ren and Yang, 2007), e.g., the average annual tem- average temperature from 1990 to 1999 was the high- peratures in Shaanxi and Gansu provinces, and est in the millennium (Qin et al., 2002). Ningxia Hui autonomous region in the past 50 years In the 20th century, the temperature in China has displayed a rising trend, with higher increase in winter risen by 0.4−0.5ºC, which is slightly lower than the and spring, while the precipitation showed a decreas- world’s average (Ding et al., 2002; Wang et al., 2002). ing trend (Ding and Yan, 2007). The climatic variation Northeastern China is one of the most sensitive re- trend in Minqin basin (1953–2004) was researched gions responding to global warming, where the aver- (Ding et al., 2007), however, the effect of climatic age temperature in the past 20 years rose by 1ºC (Sha et al., 2002). The temperature rising in the northeast Received 2011-01-25; accepted 2011-03-16 and north of China as well as in Xinjiang Uygur * Corresponding author: ZhaoFeng CHANG (E-mail: [email protected]) No.3 ShuJuan ZHU et al.: Temperature and precipitation trends in Minqin Desert during the period of 1961−2007 215 warming on precipitation was not analyzed. The response of temperature rising to global warm- ing was distinct in different regions with varying land forms (Ding, 2002). In arid and semi-arid areas, the eco-environment is closely related to temperature ris- ing (Hu et al., 2001; Ma et al., 2002; Zha, 2002; Zhao et al., 2002; Yan et al., 2003). The climate in desert is quite different from that in other regions (Chang and Zhao, 2006). How does Minqin, the typical desert area in northern China, respond to global warming? Kitoh et al. (1997), applying a global coupling atmos- phere–water circulation model, researched the varia- tion of summer wind in Asia when the air CO2 content Fig. 1 Location of the study area increased. The result revealed that the rainfall induced by summer monsoon from the India Ocean was ap- inside and around the oasis. Due to insufficient water 4 2 parently increased with global warming. The studies supply, the farmland of 2 × 10 hm in the lower by Jin et al. (2005) and Leng et al. (2007) indicated reaches of the Shiyang River has been abandoned. The that the increase/decrease of precipitation in the arid abandoned land was desertified. Secondly, large areas areas of northwest China was, to some extent, related of vegetation withered and died, and rangeland de- to the global temperature rise/drop. The aim of the graded. In the 1960s and 1970s, large numbers of research is to analyze the trends of precipitation and sand-fixing trees such as Eleganus angustifolia were temperature, and their relationship in Minqin Desert. planted in Minqin. However, Eleganus angustifolia with an area of 300 hm2 was dead, and that of 5,800 1 Study area hm2 is now at a verge of death. Sixty percent of Haloxylon ammondendron trees with an area of 44.6 Minqin county is located at the lower reaches of the hm2 is not growing well or degrading. The area of Shiyang River in northwestern Hexi corridor in Gansu natural Nitraria tangutorum is 73,300 hm2. However, province, and the western fringe of Tengger Desert the coverages of less than 30% and 10%, which ac- (102°03′–104°03′E, 38°05′–39°06′N), with an area of 2 count for 67.7% and 17.5%, respectively. At the be- 16,016 km and the elevation of 1,300–1,350 m. The ginning of the 1980s, there was Populus euphratica of landscape in Minqin can be classified into 3 types: the 372.6 hm2 in Minqin, however, the plant species dis- natural one in Han dynasty (2,100 years ago), the de- appeared now. The desertified rangeland in Minqin graded one since Han dynasty, and the man-made one has still be degrading at a large area now. Thirdly, the since 1949. gales and sandstorms occurred more frequently. The Minqin is characterized by the typical desert land- data observed by Minqin Desert Control Experiment scape. Statistic result shows that the desert, gobi, al- Station showed that there was annually 28.2-day gales kali-saline land, low hills and dunes occupy 94.2% of 2 with ≥17 m/s, 25.8-day sandstorm, 37.8-day sand- the total area, among which desert area is 8,813.3 km driven wind, and 30.2-day dust drift since the 1970s. (55.03%), gobi 800.0 km2 (5.0%), desertified range- 2 Eco-environment degradation in Minqin has at- land 5,466.67 km (34.13%). The total population is tracted the attention from China’s central government. 307,200 and the population density is 19.18 per- 2 The central government has invested over 4 billion sons/km . yuan to restore the degraded eco-environment in Min- At present, the eco-environmental degradation be- qin (Zhao, 2007). comes worse in Minqin, which is reflected in the foll- owing three aspects. Firstly, the underground water 2 Methods dramatically drops. Since the 1950s, great amount of groundwater was used for irrigation, which resulted in 2.1 Data more than 20-m drop of water table and water shortage The meteorological data during the period of 216 JOURNAL OF ARID LAND Vol.
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