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Based on the long-term trends analysis of five meteorological parameters (temperature, precipitation, wind speed, sunshine duration and relative humidity) in the four chosen stations of different settings, this paper attempts to reveal the characteristics of climate change in Urumqi City during 1960–2013. Our analytical results showed that both the temperature and precipitation in the Urumqi City have increased significantly since the middle 1980s. Autumn was the season when the temperature increased most drastically, and winter was the season when the precipitation increased most drastically. The average minimum temperature increased faster than the average maximum temperature, thus resulting in greatly reduced diurnal and annual temperature ranges. The wind speed was weakening significantly since the middle 1980s. The sunshine duration did not display any geographic coherence or consistency among different stations. The relative humidity has maintained more or less a constant, meaning that the absolute amount of water vapor has been increased under warming conditions. Comparatively, the Urumqi station (i.e., the urbanized area) had the most pronounced changes in temperature, precipitation and sunshine duration and the most pronounced changes were possibly due to the combined effects of natural and anthropogenic factors. Climate change in the mountainous area was synchronous with that in the plain area and the underlying surfaces and topographies, together with degrees of human activities, distinguished the regional climatic responses to global warming. [ABSTRACT FROM AUTHOR]

Based on the data of five observed meteorological elements (temperature, precipitation, wind speed, sunshine duration, and relative humidity) from 22 stations, the paper investigated the climate variations in northern Xinjiang over the past 50 years. The analytical results showed that both the temperature and the precipitation have increased significantly (0.35 °C/10 y, 11.2 mm/10 y) during the period of 1960–2011. An abrupt change was detected to have occurred in 1986 for temperature and in 1987 for precipitation. Autumn was the season when the temperature increased most dramatically, and winter and autumn were the seasons when the precipitation increased most dramatically. The twenty years after 1990 were the warmest and wettest two decades of the past ∼50 years, but the warming and wetting paces have slowed down during the same period. The results also showed that the mean annual minimum temperature increased more dramatically than the mean annual maximum temperature, resulting in a greatly reduced diurnal range. The reasons or mechanisms for rising trend of temperature during the past 50 years and also for the faster rising rate of the temperature in northern Xinjiang and the adjacent areas have been reasonably explored in published literature. However, the reasons or mechanisms for the rising trend of the past 50-year precipitation in northern Xinjiang and the adjacent areas have not been reasonably explored. This wetting trend has not extended further to the surrounding areas including Republic of Mongolia, major part of North China, and five republics of the former Soviet Union, and the need is thus pressing to explore the reasons or mechanisms behind this relatively “localized” wetting trend. [ABSTRACT FROM AUTHOR]

Abstract: Climate extremes in the Tibetan Plateau may cause serious regional and global consequences, but observation-based research over the western Tibetan Plateau is scarce. In this paper, recent changes in extremes of temperature and precipitation over the western Tibetan Plateau from 1973 to 2011 are investigated. A total of 24 indices that represent extreme climate events are selected and calculated by using daily maximum and minimum temperature and precipitation data. Results demonstrate that most cold-related indices of temperature extremes (frost and ice days, cool nights and cool days, and cold spell duration indicators) show a significant decrease, and that both the coldest night and coldest day have increased during the study period. Warm-related indices of temperature extremes such as summer days, the warmest night and the warmest day, warm nights and warm days, and warm spell duration indicators all have increased. The diurnal temperature ranges show a decreasing trend with statistical significance, whereas growing season lengths have increased significantly. The change trends of precipitation extremes are nonsignificant. Nonsignificant increasing trends are detected for most indices including annual total wet-day precipitation, maximum 1-day and 5-day precipitation, very wet and extremely wet day precipitation, and consecutive wet days. However, nonsignificant decreasing trends are found for the number of heavy precipitation days, consecutive dry days and simple daily intensity index. [Copyright &y& Elsevier]