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Highlights from the article: However, most surge-type glaciers are characteristically long and wide (Barrand and Murray, [1]), while the Aru Glacier is a relatively small glacier with low annual accumulation and slow velocity. Thus, the evidence of glacier sliding might suggest that these glaciers are now in transition from cold base to polythermal due to warming conditions in the region, which thus may threaten the stability of this type of glacier. If the climate warming in the region is the primary cause of the Aru Glacier collapse, then it will not be the last one (the neighboring glacier collapsed on 21 September 2016, with a detached ice area of 6.3 km SP 2 sp and fallen ice volume of ~100 million m SP 3 sp , comparable with the first one).

Changes in glacial geometries (extent and surface elevations) in the Ayilariju region of Western Himalaya, China, were investigated using topographical maps and data from the Landsat Thematic Mapper/Enhanced Thematic Mapper Plus, the Satellite Pour l'Observation de la Terre (SPOT4), the Shuttle Radar Topography Mission 4.1 digital elevation model, and geographical information system techniques. The results showed that the total glaciated area decreased from 190.37 to 162.52 km (14.6 % of the 1980 glaciated area) from 1980 to 2011. Furthermore, total glacial mass loss of studied region was estimated to be 2.570 ± 0.327 km between 1980 and 2000. Further investigation on meteorological data indicated that increases of temperature and total radiation were the primary causes of accelerated glacial melting. Reduced wind speed and slight decreases in precipitation triggered by weakening of the South Asian summer monsoon due to warming, may also have contributed to glacial shrinkage. The rate of glacial retreat in the studied region is lower than that in the southern Himalayan region, but larger than that in the Karakoram, primarily because Ayilariju glaciers were located on the margin of the Indian monsoon dominated region. [ABSTRACT FROM AUTHOR]

The southeastern Chinese Loess Plateau is the terminal deposition area of dusts transported by the East Asian winter monsoon and the frontal area penetrated by the East Asian summer monsoon, and thus a climate sensitive region. This paper reports a rock magnetic study of a Quaternary loess-paleosol section in such a region. We tried to reconstruct the paleoclimate evolution history in the region during 1.95-0.40 Ma with magnetic parameters. The results show a general up-section decreasing trend of the ratio of HIRM/(SIRM-IRM), indicating a long-term decreasing trend of hematite coercivities in the deposits, which can be mainly related to the cooling and aridification trend of the environment in interglacial depositional area and glacial dust source region. The ratio, χ/ χ, widely used to reflect the variations of magnetic mineral grain size, manifests a long-term increasing trend of the magnetic mineral grain size and tends to indicate an overall weakening trend of the East Asian summer monsoon that controlled the pedogenic intensity. Although the regional multi-segmented paleoclimatic records revealed by several magnetic parameters in our study, the long-term Asian cooling and aridification trend inferred here is of global correlation significance. [ABSTRACT FROM AUTHOR]

A high-resolution loess section in the western Chinese Loess Plateau, Yuanbao Section, was sampled for organic carbon isotopic analyses. The soil organic carbon isotope (δ Corg) varied between -22.6‰ and -27.5‰ during the last glacial at the section. During the last interstadial, the δ Corg values were more negative than those in both early and late periods of the last glacial by 4‰. The isotopic composition indicates a coupled response of the pure C3 plants to the temperature, precipitation and the concentration of atmospheric CO2. Decrease in temperature and the atmospheric CO2 concentration from the last interstadial to Last Glaicial Maximum (LGM) caused the organic carbon isotopes to become positive by 1.5‰ 2.0‰. The amplitude of 4‰ in the δ Corg variation during the last glacial should be mainly caused by the precipitation change. Therefore, the δ Corg variations of the Yuanbao Section during the last glacial period documented the large-amplitude fluctuation of the monsoon precipitation, which is estimated to be 250-310 mm more during the last interstadial than that in the LGM, and 100 mm more than that during early last glacial. The rapid changes of the monsoon precipitation on millennial scale during the last glacial have also been recorded in the isotopic variations in Yuanbao loess section. As the isotopic composition varies complicatedly as shown in the loess-paleosol sequence, it cannot be simply attributed to the abundances of C3 and C4 plants or be used as an indicator of the summer monsoon variations. [ABSTRACT FROM AUTHOR]