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A very strong summer monsoon event during 30–40 kaBP in the Qinghai-Xizang (Tibet) Plateau and its relation to precessional cycle
Yafeng Shi,Xiaodong Liu,Bingyuan Li,Tandong Yao
Chinese Science Bulletin , 1999, DOI: 10.1007/BF02886339
Abstract: Guliya ice core records, high lake-level records in the Qinghai-Xizang Plateau and at its north side as well as vegetation succession records indicated that during the period of 30–40 kaBP, namely the later age of the megainterstadial of last glacial period, or the marine oxygen isotope stage 3, the climate of the Qinghai-Xizang Plateau was exceptionally warm and humid, the temperature was 2–4°C higher than today and the precipitation was 40% to over 100% higher than the current average, all these suggested the existence of an exceedingly strong summer monsoon event. It has been inferred that the occurrence of such an event was attributed, on the one hand, to the stronger summer low pressure over the Plateau, which strengthened the attraction to the summer monsoon; on the other hand, to the vigorous evaporation of the tropic ocean surface, which promoted the moisture-rich southwest monsoon to flow over the Qinghai-Xizang Plateau. The background responsible for the formation of the very strong summer monsoon was that the period of 30–40 kaBP was just in the strong insolation stage of the 20ka precessional cycle, when the Qinghai-Xizang Plateau received extraordinary strong solar radiation and thus enlarged the thermodynamical contrast between the Plateau and the midsouth part of the Indian Ocean.
Interannual Variability of Atmospheric Heat Source/Sink over the Qinghai-Xizang (Tibetan) Plateau and its Relation to Circulation

Zhao Ping,Chen Longxun,
Zhao Ping
,Chen Longxun

大气科学进展 , 2001,
Abstract: Based on the 1961-1995 atmospheric apparent heat source/sink and the 1961-1990 snow-cover days and depth over the Qinghai-Xizang Plateau (QXP) and the 1961-1995 reanalysis data of NCEP/NCAR and the 1975-1994 OLR data, this paper discusses the interannual variability of the heat regime and its relation to atmospheric circulation. It is shown that the interannual variability is pronounced, with maximal variability in spring and autumn, and the variability is heterogeneous horizontally. In the years with the weak (or strong) winter cold source, the deep trough over East Asia is to the east (or west) of its normal, which corresponds to strong (or weak) winter monsoon in East Asia. In the years with the strong (or weak) summer heat source, there exists an anomalous cyclone (or anticyclone) in the middle and lower troposphere over the QXP and its neighborhood and anomalous southwest (or northeast) winds over the Yangtze River valley of China, corresponding to strong (or weak) summer monsoon in East Asia. The summer heat source of the QXP is related to the intensity and position of the South Asia high. The QXP snow cover condition of April has a close relation to the heating intensity of summer. There is a remarkable negative correlation between the summer heat source of the QXP and the convection over the southeastern QXP, the Bay of Bengal, the Indo-China Peninsula, the southeastern Asia, the southwest part of China and the lower reaches of the Yangtze River and in the area from the Yellow Sea of China to the Sea of Japan.
Characteristics of the Lows Flocking with Tibet Atmospheric Low-Frequency Oscillation over the Qinghai-Xizang (Tibet) Plateau

Sun Guowu,Chen Baode,

大气科学 , 1994,
Abstract: This paper shows that the Qinghai-Xizang (Tibet) Plateau lows have the flocking characteristicsduring the summer half-year, i.e., the lows occur flockingly during a period,but they do not occur dur-ing other periods.The period of lows flocking is related to the intensity of the high-frequency disturb-ance over the Qinghai-Xizang Plateau as well as phase shifts and vertical structure of the low-frequen-cy oscillation over the plateau.This relationship may represent the interaction of disturbances (bothhigh-frequency and low-frequency) of the atmosphere over the plateau.
An Experiment on the Northern Qinghai-Xizang Plateau Land Surface Model

Zhang Yu,Lu Shihua,

大气科学 , 2002,
Abstract: Key words: land surface model; Qinghai-Xizang (Tibetan) Plateau; numerical simulation
Impacts of anomalies of thermal state over the Qinghai_Xizang Plateau and sea surface temperature on interannual variability of the Asian monsoon seasonal transition

MAO Jiang-Yu,WU Guo-Xiong,

地球物理学报 , 2006,
Abstract: Based on the reversal of the middle and upper tropospheric meridional temperature gradient near the ridge surface of the Asian subtropical anticyclone during seasonal transition, correlation and composite analyses are employed to study the interannual variability of the Asian monsoon seasonal transition and its relation to external forcing. Results show that ENSO and thermal state over the Qinghai-Xizang Plateau in the preceding winter and spring are two dominant factors responsible for the interannual variability of the Asian monsoon seasonal transition. When the E1 Nino event occurs during winter and spring, Walker circulation is weakened so that deep convection is suppressed over the western Pacific warm pool, while enhanced convection over the eastern equatorial Pacific induces adiabatic descending motion over the equatorial Indian Ocean. Consequently, air temperature over the equatorial Indian Ocean gets wanner, meridional temperature gradient over Asian sector becomes larger, and the seasonal transition is later than normal. The middle and upper tropospheric temperature anomalies over the Qinghai-Xizang Plateau in early spring are good indicative of predicting abnormal seasonal transition.
Functions, patterns and countermeasures combining farming with stockbreeding on the Qinghai -Xizang Plateau

WEN Jun,

自然资源学报 , 2000,
Abstract: There are multi nationalities on the Qinghai Xizang Plateau.The way of their existence and the stockbreeding oriented resources utilization mode constitute a major feature of plateau agricultural development.This article makes perspective analyses of the functional features of the Qinghai Xizang Plateau, and finds that four kinds of alternative production patterns of Combining Farming with Stockbreeding, namely, central farming areas, peripheral farming areas, central stockbreeding areas, and peripheral stockbreeding areas have been formed on the Plateau.It is believed that only measures are taken to promote the organic combination of farming with stockbreeding, can the modenazational process in sustainable agricultural development of the Qinghai Xizang Plateau be quickened,so as to ensure food security of all nationalities on the plateau.
Comprehensive geophysical profile and lithosphere structures and geodynamics in western Qinghai-Xizang (Tibetan) Plateau
Xiangru Kong,Qianshen Wang,Shaobai Xiong
Chinese Science Bulletin , 1999, DOI: 10.1007/BF02884914
Abstract: A comprehensive study in this paper for the lithosphere velocity structure, conductivity structure, density and magnetism structure at the Qinghai-Xizang(Tibetan) Plateau has been completed based on the data of gravity, geomagnetism, and magneto-telluric sounding (MTS), explosion seismology acquired on the comprehensive geophysical profile along Gyirong-Sangehu. It presents the deep and shallow structural features of blocks, suture zones, and faults. Meanwhile, the lithosphere structure at the east and west parts of the plateau has been crossstudied and the deep structure of the plateau and the geodynamic models have been discussed according to the geophysical data available for the Qinghai-Xizang (Tibetan) Plateau.
Structural Variation of Atmospheric Heat Source over the Qinghai-Xizang Plateau and its Influence on Precipitation in Northwest China the Qinghai-Xizang Plateau and Its Influence on Precipitation in Northwest China

WEI N,GONG Yuanfa,HE Jinhai,

大气科学进展 , 2009,
Abstract: NCEP/NCAR reanalysis data and a 47-year precipitation dataset are utilized to analyze the relationship between an atmospheric heat source (hereafter called < Q1 >) over the Qinghai-Xizang Plateau (QXP) and its surrounding area and precipitation in northwest China. Our main conclusions are as follows: (1) The horizontal distribution of < Q1 > and its changing trend are dramatic over QXP in the summer. There are three strong centers of < Q1 > over the south side of QXP with obvious differences in the amount of yearly precipitation and the number of heat sinks predominate in the arid and semi-arid regions of northwest China (NWC), beside the northern QXP with an obvious higher intensity in years with less precipitation. (2) In the summer, the variation of the heat source's vertical structure is obviously different between greater and lesser precipitation years in eastern northwest China (ENWC). The narrow heat sink belt forms between the northeast QXP and the southwestern part of Lake Baikal. In July and August of greater precipitation years, the heating center of the eastern QXP stays nearly over 35oN, and at 400 hPa of the eastern QXP, the strong upward motion of the heating center constructs a closed secondary vertical circulation cell over the northeast QXP (40o--46oN), which is propitious to add precipitation over the ENWC. Otherwise, the heating center shifts to the south of 30oN and disappears in July and August of lesser precipitation years, an opposite secondary circulation cell forms over the northeast QXP, which is a disadvantage for precipitation. Meanwhile, the secondary circulation cell in years with more or less precipitation over the ENWC is also related to the heat source over the Lake Baikal. (3) The vertical structure of the heat source over the western QXP has obvious differences between greater and lesser precipitation years in western northwest China in June and July. The strong/weak heat source over the western QXP produces relatively strong/weak ascending motion and correspondingly constructs a secondary circulation cell in lesser/greater precipitation years.

Wen Jim Ji Guoliang Zhang Wanchen,

地理研究 , 1993,
Abstract: In this paper, the calculated method of atmospheric turbidity over the Qinghai-Xizang Plateau is obtained by comparison of various methods to calculate A ngstrom atmospheric turbidity. The atmospheric-turbidity ciefficients at some stations over the Qinghai-Xizang Plateau from August 1982 to July 1983 are calculated by using the observational data of solar direct radiation .and their characteristics are analysed. In addition, the empiric formula to calculate atmospheric turbidity coefficients are fitted by means of surface conventional meteorological data, the characteristics of temporal and spatial variations are analysed over the Qinghai-Xizang Plateau in thie paper

Huang Zhongshu,

地理研究 , 1986,
Abstract: This paper describes overall the correlation analysis of the air temperature at eight basic stations in the East Qinghai-xizang Plateau and the precipitation in water season on Yangtze River basin.It is found in the chart that there is an obvious maximun value of monthly mean air temperature in the plateau in March,August and December last year.The appearance of three high correlation stages is not occasional. The variation from month to month shows that three stages are also with higher continuity.This paper has emphatically analysed the variation of the atmospheric circulation ultra-long wave in the three warm and three cold years of the plateau.It is outlined that,(1) the change of the energy density of ultra-long wave in lower and higher atmospheric layer, on middle-low and high latituae zones in the cold and warm year of the plateau is completely different, that is, on one side the energy density incre-, ases and on the other side it decreases. (2) The difference of the trough and ridge line distribution' of the atmospheric ultra-long wave in cold and warm year is the greatest in middle-low and high latitude zones, too,but the tendency of their change is in the opposite direction.In the middle latitude transition zone (40-60°N) the difference of the density between cold and warm years is not observable (3) In summer on subtropical zone from East Asia to West Pacific Ocean(75-175°E) there exist mainly three latitude circulation cells,the variation of which in cold and warm year of the plateau is an oscillation as billow, i.e.as one cell is strengthened (or weakened), the other two neighboring cells are weakened (or strengthened).
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