Middle East China Research Articles

Relationship between Extreme Precipitation and Temperature in Two Different Regions: The Tibetan Plateau and Middle-East China

The change of extreme precipitation with temperature has regional characteristics in the context of global warming. In this study, radiosonde data, co-located rain gauge (RG) observations, and Tropical Rainfall Measuring Mission (TRMM) precipitation radar (PR) products are used to explore the relationship between extreme precipitation intensity and near-surface temperature in Middle–East China (MEC) and the eastern Tibetan Plateau (TP) during 1998–2012. The results show that extreme precipitation intensity increases with increasing temperature at an approximate Clausius–Clapeyron (C–C) rate (i.e., water vapor increases by 7% as temperature increases by 1°C based on the C–C equation) in MEC and TP, but the rate of increase is larger in TP than in MEC. This is probably because TP (MEC) is featured with deep convective (stratiform) precipitation, which releases more (less) latent heat and strengthens the convection intensity on a shorter (longer) timescale. It is also found that when temperature is higher than 25°C (15°C) in MEC (TP), the extreme precipitation intensity decreases with rise of temperature, suggesting that the precipitation intensity does not always increase with warming. In this case, the limited atmospheric humidity and precipitable water could be the primary factors for the decrease in extreme precipitation intensity at higher temperatures.

Analysis of water vapor effects on aerosol properties and direct radiative forcing in China

The effects of column water vapor (CWV) on aerosol optical properties, radiative effects and classification are studied by using aerosol and CWV data from eight Aerosol Robotic Network (AERONET) sites in China: Beijing, XiangHe, Shouxian, Taihu, Hong_Kong, Zhongshan_Univ, SACOL, and Mt_WLG, which represents 5 distinct aerosol climatologies in China. Contrast in correlations between aerosol optical depth (AOD) and CWV is found. High correlation coefficient (R) ranging from 0.63–0.94 is observed at Beijing and XiangHe (North China Plain), SACOL (Northwest China) and Mt_WLG (the Tibetan Plateau). R values at stations in the Middle-East China (Shouxian and Taihu) are within 0.32–0.45. AOD shows poor correlation to CWV in Southeast China (R at Hong_Kong and Zhongshan_Univ of 0.15 and 0.27). At most sites, the asymmetry (ASYM) of fine-mode aerosol increases with CWV with R larger than ~0.4. Aerosol direct radiative forcing efficiency (ADRFE) at the bottom of the atmosphere (BOA) is affected by CWV, with R >~0.5 over the north and Middle-East China sites. The statistic results show that an increase of CWV by 0.1 cm could result in enhancements of ADREF at the BOA by about 1.1–2.8 W m−2 at all the sites except Mt_WLG. The aerosol classification shows that the mix-small aerosol type is always dominated under the high CWV air. The clusters of back-trajectories with relative humidity (RH) from Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model indicate that the air mass with high RH is often from south and east directions. The influence of CWV on aerosol properties is mainly shown in the properties of fine mode aerosol, which needs to be considered in the study of aerosol radiative forcing and climate effects.

Genetic analysis of mitochondrial DNA control region variations in four tribes of Khyber Pakhtunkhwa, Pakistan

Due to its geo strategic position at the crossroad of Asia, Pakistan has gained crucial importance of playing its pivotal role in subsequent human migratory events, both prehistoric and historic. This human movement became possible through an ancient overland network of trails called “The Silk Route” linking Asia Minor, Middle East China, Central Asia and Southeast Asia. This study was conducted to analyze complete mitochondrial control region samples of 100 individuals of four major Pashtun tribes namely, Bangash, Khattak, Mahsuds and Orakzai in the province of Khyber Pakhtunkhwa, Pakistan. All Pashtun tribes revealed high genetic diversity which is comparable to the other Central Asian, Southeast Asian and European populations. The configuration of genetic variation and heterogeneity further unveiled through Multidimensional Scaling, Principal Component Analysis and phylogenetic analysis. The results revealed that Pashtun are the composite mosaic of West Eurasian ancestry of numerous geographic origin. They received substantial gene flow during different invasive movements and have a high element of the Western provenance. The most common haplogroups reported in this study are: South Asian haplogroups M (28%) and R (8%); whereas, West Asians haplogroups are present, albeit in high frequencies (67%) and widespread over all; HV (15%), U (17%), H (9%), J (8%), K (8%), W (4%), N (3%) and T (3%). Moreover, we linked the unexplored genetic connection between Ashkenazi Jews and Pashtun. The presence of specific haplotypes J1b (4%) and K1a1b1a (5%) pointed to a genetic connection of Jewish conglomeration in Khattak tribe. This was a result of an ancient genetic influx in the early Neolithic period that led to the formation of a diverse genetic substratum in present day Pashtun.

Performance evaluation of the simulated daily average temperature series in four seasons in China by Beijing Climate Center climate system model

In the present paper, the detrended fluctuation analysis (DFA) method is first used to analyze the daily average temperature records in four seasons in China, and the results show that the seasonal temperature records exhibit long-range correlation in China, especially in Xinjiang and Xizang in western China. Based on the long-range correlation in observational temperature records, we use DFA to evaluate the performances of the simulated daily average temperature series in four seasons in China by Beijing Climate Center climate system model (BCC_CSM) (1.1 m), and find that the BCC_CSM (1.1 m) can reflect the long-range correlations in different seasons. In general, the simulated results are best in spring except for the bad performance in Jiangnan. In summer, the simulation performance is poor in middle-east China and most areas in Tibet, especially in the southern North China, western Huanghai, Jiangnan and South China. The long-rang correlation of the simulated data for autumn is stronger in Northeast China, southeast North China, while weaker in the most of Northwest China. In winter, except for the eastern seaboard, the simulated long-range correlations of daily temperature are weaker than that of observational records in most China. And the simulated performance is poor in Northwest China, Southwest China, northern South China, southern Jiangnan and northern Northeast China, especially in the western Tibet.