Five‐Year Analysis of Evaposublimation Characteristics and Its Role on Surface Energy Balance SEB on a Midlatitude Continental Glacier

Abstract

As a crucial component of cryosphere, the glacier has been considered as an excellent indicator of climate change (Fernandez & Mark, 2016;GTOS, 2008;Oerlemans & Reichert, 2000). With special thermodynamic and hydrological characteristics, the glacier' sublimation play a significant role in exchange process of water and heat between the cryosphere and atmosphere, and thus can be the important factor in regional, even global water and energy balances, as well as the atmospheric circulation (De'ry & Yau, 2002;Suzuki et al., 2015). Under the context of climate warming, the melt of glacier is shifted to an earlier date, the corresponding melt period is prolonged, and the sublimation or evaporation process is likely to be more intense. As a result, there are bound to be changes in spatial and temporal scales of water and energy balances, and thereby affecting the regional water resources and ecological environment.Based on the Randolph Glacier Inventory (RGI 6.0) published in 2017, Mu et al. (2018) analyzed the current situation and recent change of global glacierized area, and found that the total number of mountain glaciers was about 215500 around the world (excluding the Antarctic and Greenland ice sheets). In the middle and low latitudes, the mountain glaciers are more prominent in Tibetan Plateau (TP) and Surroundings, which are known as the Asia's water tower, and providing significant water resources for the arid and semiarid regions that are characterized by relatively less precipitation and more crucial snow or ice melting for the middle and lower reaches (Immerzeel

Surface Sublimation/Evaporation and Condensation/Deposition and Their Links to Westerlies During 2020 on the August‐One Glacier, the Semi‐Arid Qilian Mountains of Northeast Tibetan Plateau

“…Both had high seasonal variabilities with the largest absolutes in spring (Figure 6a). This was related to the relatively more snowfalls (high albedo) and fewer cloud covers during the spring of this glacier (Guo et al., 2021). However, the monthly mean of net shortwave radiation S in summer reached to 82 W m −2 , which was much larger than other seasons.…”

“…The energy and mass balances of the glaciers in Qilian Mountains are bound to be profoundly affected by the seasonal variation in westerlies. Studies revealed that the surface sublimation on the TP glaciers is more intense during the dry or non‐melt period with dry air and strong winds (e.g., Guo et al., 2021; Li et al., 2018; Liu et al., 2021). Therefore, the westerlies may also be the most crucial driver of sublimation by affecting the main meteorological factors on the August‐one glacier.…”

“…Because of the special geographical location, the Qilian Mountains is severely affected by the Gobi and deserts distributed in northern China and southern Mongolia (Zhao et al., 2014). The accumulation of mineral dust together with carbonaceous particles and organic matters (the light‐absorbing impurities) is clearly visible during summer on the August‐one glacier surface, which is closely related to the low albedo, high ice temperature and intense melting (Guo et al., 2021).…”

Climate Warming Favoring Sublimation on a Westerlies‐Controlled Glacier of Tibetan Plateau

“…However, winds were more moderate and quite weak over summer (mean u = 3.5 m s −1 ), with a minimum average of 3.3 m s −1 in August. In addition, wind speed is found to be higher during the daytime than during night (Guo et al., 2021). Figure 2b showed that the west wind direction prevailed over the study glacier, while the mean wind direction WD was significantly lower during summer than that of other seasons.…”

“…Under the influence of Indian monsoon, the glacier sublimation/evaporation was relatively small, and ablation was controlled by melting, which can provide a large amount of water resources for rivers, while when the glacier weather was dominated by westerlies (more arid and windy), the glacier mass loss was dominated by sublimation (Wang et al., 2019). Sublimation has been identified to be important for the mass loss of TP glaciers during winter due to the arid and windy weather conditions, and can have a great influence on glacier accumulation (e.g., Guo et al., 2021; Mandal et al., 2022; Stigter et al., 2018). For the glaciers on the northern TP (controlled by westerlies all year round), glacier mass losses due to sublimation or evaposublimation have been found to be responsible for 29% of the annual precipitation on the Laohugou glacier (Sun, 2012) and to be 14.5% on the August‐one glacier (Guo et al., 2021).…”