Recent climate trends on the northern slopes of the Tianshan Mountains, Xinjiang, China

Abstract

Abstract:In arid regions, mountains fulfill important ecological and economic functions for the surrounding lowlands. In the scenario of global warming, mountain ecosystems change rapidly, especially in the arid region of northwestern China. This paper provides an assessment of the changes in temperature and precipitation in the historical records of climate on the northern slopes of the eastern Tianshan Mountains. A Mann-Kendall nonparametric trend and Sen's tests are employed to analyze the interannual changes and innerannual variability in temperature and precipitation in the regions of low to high altitude. The present study finds that the largest increases in annual temperature are observed at stations in the low altitude regions. The significant increasing trends in temperature tend to occur mainly in late winter and early spring at stations from middle to high altitude, but in summer and autumn at stations of low altitudes. The increasing trends in annual precipitation are found from the middle to high altitude areas, but decreasing trends are found in the low altitude areas. The significant increasing trends in precipitation occur mostly in winter and earlier spring at stations from the middle to high altitudes, while the increasing and decreasing trend coexists at stations of low altitude with most of the significant trend changes occurring in March, June and August.

Trend Analysis of Precipitation in the Jinsha River Basin in China

“…Although the trends are not significant, the precipitation is generally increasing as evident from the positive values of the MK trend magnitude, b. Twentyfour out of 30 stations exhibited an increasing trend and 3 of them were statistically significant at the level of a 5 0.05, while 6 out of 30 stations exhibited a decreasing trend and only 2 of them were statistically significant at the level of a 5 0.05 for mean annual precipitation. It further proves that the variation magnitude of the high elevation is more significant than that of precipitation at the low-elevation places (Wilhelm et al 2012;Zhang et al 2009;Hou et al 2002). The results also show that high-elevation climate in the region, such as the headwater of the JRB in this paper, may be greater increasing trend magnitudes than those at lower elevations.…”

Absence of late-summer warming trend over the past two and half centuries on the eastern Tibetan Plateau

“…The warming trend in summer and autumn was relatively marginal over the northern hemisphere (Jones and Briffa, 1992;Jones and Moberg, 2003;Manabe et al, 2011). However, other studies reported that summer and autumn temperatures exhibited the largest warming trends in Asian areas (Böhner, 2006;Li et al, 2006;Zhang et al, 2009), particularly in the second half of the 20th century (Kriegel et al, 2013;Zhang et al, 2013). Zhang et al (2009) analyzed the meteorological records of six stations on the northern slope of the Tianshan Mountains of China, and found that significant warming mainly occurred in summer and autumn, especially for stations of low altitudes.…”

“…However, other studies reported that summer and autumn temperatures exhibited the largest warming trends in Asian areas (Böhner, 2006;Li et al, 2006;Zhang et al, 2009), particularly in the second half of the 20th century (Kriegel et al, 2013;Zhang et al, 2013). Zhang et al (2009) analyzed the meteorological records of six stations on the northern slope of the Tianshan Mountains of China, and found that significant warming mainly occurred in summer and autumn, especially for stations of low altitudes. Pronounced warming was observed in China in winter, spring, and autumn, particularly in the northern part of China, but a cooling trend in summer was found over central China during 1951-2000(Hu et al, 2003.…”

Recent trends of temperature change under hot and cold desert climates: Comparing the Sahara (Libya) and Central Asia (Xinjiang, China)

“…Temperature trends in arid and semi-arid regions were shown by various studies, which include El-Tantawi (2005), Domroes and El-Tantawi (2005), Ben-Gai et al (1999), Englehart and Douglas (2003), Hingane et al (1985), Lioubimtseva et al (2005), Lu et al (2009), Yang (2009 and Zhang et al (2009). Such studies have focused on dry climate regions in different parts of the world, namely on Libya, Egypt, Israel, USA, India, Central Asia, Mongolia and China.…”

“…El-Tantawi (2005) investigated climate change of Jifara Plain in Libya using climate data over the 55-years period 1946e2000 for 15 stations that correspondingly show a long-term annual temperature trend ranging between À0.04 and 0.25 C. The study of Yang (2009) is related to the arid regions in China, showing that the mean annual temperature trend has increased by 0.3 C during the 1990s in the entire region of Xinjiang. Although Zhang et al (2009) have investigated annual and monthly mean temperature trends (1961e2005) in Xinjiang, their study focused only on three mountain stations of Tianshan Mountains. Recent studies on desert areas (Eitel et al, 2005(Eitel et al, , 2006Faust et al, 2004) demonstrate that the areas concerned have been affected by environmental changes.…”