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Abstract. In order to monitor the changes of the glaciers in the Gongga Mountain region on the south-eastern margin of the Qinghai-Tibetan Plateau, 74 monsoonal temperate glaciers were investigated by comparing the Chinese Glacier Inventory (CGI), recorded in the 1960s, with Landsat MSS in 1974, Landsat TM in 1989, and ASTER data in 2009. The remote sensing data have been applied to map the glacier outline by threshold ratio images (TM4/TM5). Moreover, the glacier outlines were verified by GPS survey on four large glaciers (Hailuogou (HLG), Mozigou (MZG), Yanzigou (YZG), and Dagongba (DGB)) in 2009. The results show that the area dominated by the 74 glaciers has shrunk by 11.3 % (29.2 km 2 ) from 1966 to 2009. Glacier area on the eastern and western slopes of the Gongga Mountains decreased by 9.8 % and 14.6 % since 1966, respectively. The loss in glacier area and length is, respectively, 0.8 km 2 and 1146.4 m for the HLG Glacier, 2.1 km 2 and 501.8 m for the MZG Glacier, 0.8 km 2 and 724.8 m for the YZG Glacier, and 2.4 km 2 and 1002.3 m for the DGB Glacier. Decades of climate records obtained from three meteorological stations in the Gongga Mountains were analyzed to evaluate the impact of the temperature and precipitation on glacier retreat. The mean annual temperatures over the eastern and western slopes of the Gongga Mountains have been increasing by 0.34 K decade −1 and 0.24 K decade −1 , respectively. Moreover, mean annual precipitation has only increased by 1 % in the past 50 yr. The increasing amount of precipitation could not compensate for the glacier mass loss due to the temperature increase in the Gongga Mountains. This suggests that the warming of the climate is probably also responsible for the glacier retreat in the study region. At the region scale, glacier changes were also controlled by local topographical factors.

Airborne dust derived from desertification in northern China can be transported to East Asia and other regions, impairing human health and affecting the global climate. This study of northern China dust provides an understanding of the mechanism of dust generation and transportation. The authors used dust storm and climatological data from 129 sites and normalized difference vegetation index (NDVI) datasets in northern China to analyze spatiotemporal characteristics and determine the main factors controlling dust storms occurring during 1960–2007. Dust storm–prone areas are consistent with the spatial distribution of northern China deserts where the average wind speed (AWS) is more than 2 m s−1, the mean annual temperature (MAT) ranges from 5° to 10°C, and the mean annual precipitation (MAP) is less than 450 mm. Dust storms commonly occur on spring afternoons in a 3- to 6-h pattern. The three predominant factors that can affect DSF are the maximum wind speed, AWS, and MAT. During 1960–2007, dust storm frequency (DSF) in most regions of northern China fluctuated but had a decreasing trend; this was mainly caused by a gradual reduction in wind speed. The effect of temperature on DSF is complex, as positive and negative correlations exist simultaneously. Temperatures can affect source material (dust, sand, etc.), cyclone activity, and vegetation growth status, which influence the generation of dust storms. NDVI and precipitation are negatively correlated with DSF, but the effect is weak. Vegetation can protect the topsoil environment and prevent dust storm creation but is affected by the primary decisive influence of precipitation.

The rate and distribution of deformation along the Qilian Mountain, on the northeastern Tibetan Plateau, is needed to understand the evolution of high topography associated with the plateau. Recently, a number of empirical studies have provided support for the contention, common to most models of fluvial incision, that rock uplift rate exerts a first-order control on the gradient of longitudinal river profiles. Along the northern Qilian Mountain, this method is used to extract information about the spatial patterns of differential rock uplift. Analysis of the longitudinal profiles of bedrock channels reveals systematic differences in the channel steepness index along the trend of the frontal ranges. Local comparisons of channel steepness reveal that lithology and precipitation have limited influence on channel steepness. Similarly, there is little evidence suggesting that channel steepness is influenced by differences in the sediment loads. We argue that the distribution of channel steepness in the Qilian Mountain is mostly the result of differential rates of rock uplift. Thus, channel steepness indices reveal a lower rock uplift rate in the eastern portion of the Qilian Mountain and a higher rate in the middle and west. The highest rates appear to occur in the middle-west portions of the range, just to the west of the Yumu Shan. Qilian Mountain, stream power erosion model, channel steepness, rock uplift rate, river profile Citation: Hu X F, Pan B T, Kirby E, et al. Spatial differences in rock uplift rates inferred from channel steepness indices along the northern flank of the Qilian Mountain, northeast Tibetan Plateau.

Global warming is causing widespread glacier retreat, with small glaciers disappearing. We investigate changes in glaciers over the western Lenglongling mountains, located in the northeastern margin of the Tibetan Plateau. Glacier extent over the western Lenglongling mountains is estimated by comparing digitized glacier outlines obtained from aerial photographs and satellite imagery. These results suggest that all 179 glaciers in the western Lenglongling mountains shrunk between 1972 and 2007. The total area loss was ~24.4 km2, accounting for ~28.3% (0.81% a-1) of the glacierized area in 1972. The average area retreat rates differ over different time intervals: they are approximately 0.68, 0.90, 0.77 and 0.56 km2 a-1 over the periods 1972-95,1995-99,1999-2002 and 2002-07, respectively. Based on analysis of meteorological data, glacier shrinkage in the study area can probably be attributed to the increase in air temperature. Furthermore, the smaller glaciers display a higher shrinkage rate than larger glaciers, and glaciers on southwest-facing slopes appear to retreat faster than those on northeast- facing slopes.