Vertical influence of temperature and precipitation on snow cover variability in the Yarlung Zangbo River basin, China

Abstract

Seasonal snow cover in mountainous areas is a key source of water for downstream regions. The snow cover area (SCA) in the Northern Hemisphere has significantly decreased during the past decades in response to global warming. Therefore, it is necessary to investigate the primary factors controlling the spatiotemporal variabilities in the SCA in high altitude regions. In this study, based on remote sensing data of SCA, temperature, and precipitation in the Yarlung Zangbo River basin, Pearson's correlation analysis was used to identify the relative importance of temperature and precipitation on the SCA variability with altitude. The results showed that temperature played a more dominant role for the SCA than precipitation at all elevation during the period 2001–2017; three threshold altitudes at high, moderate, and low elevation were identified, and these threshold altitudes are dynamic and vary with time; the threshold altitude at high elevation was 5,925 ± 125 m, below which temperature (precipitation) was negatively (positively) correlated and above which temperature (precipitation) was positively (negatively) correlated with the SCA; the threshold altitude at moderate elevation was 3,200 ± 300 m, below which temperature (precipitation) was positively (negatively) correlated and above which temperature (precipitation) was negatively (positively) correlated with the SCA; the threshold altitude in low elevation regions was 2,100 ± 200 m. This study sheds light on the dominant climatic control factors on the variability in SCA in high altitude regions. These results have major implications for SCA and water resources availability under future climate change.

The Spatiotemporal Regime of Glacier Runoff in Oases Indicates the Potential Climatic Risk in Dryland Areas of China

“…Previous studies have shown that the range of glacier change is larger in wetter mountains, such as Eastern Qilian Shan and the Western Tien Shan, while the range of glacier change decreases with the distance from a water vapor supply source. Most studies also showed that temperature played a leading role in hydrothermal conditions, while precipitation played a weaker role (Azam & Srivastava, 2020;Ban et al, 2020;Baojuan et al, 2020;Noel et al, 2020).…”

Impact of variability in the hydrological cycle components on vegetation growth in an alpine basin of the southeastern Tibet Plateau, China

“…The YZR is the highest river in the world with an average elevation of over 4,000 m. The drainage area of the YZR basin (27°40 0 -31°15 0 N, 82°00 0 -97°15 0 E) is approximately 2.4Â10 5 km 2 , and the range of its elevation is 152-7,182 m. The YZR basin has a complex topography and includes several different climate zones from its lower reaches to the upper reaches. The YZR has five major tributaries, i.e., the Duoxiong Zangbo River, Nianchu River, Lhasa River, Nyang River, and Parlung Zangbo River (Ban et al 2020). Average annual precipitation in the upper reaches to the lower reaches varies from 200 to 5,000 mm, respectively (Li et al 2014).…”

Comment on hess-2021-377

“…of glacier change decreases with the distance from a water vapor supply source. Most studies also showed that temperature played a leading role in hydrothermal conditions, while precipitation played a weaker role (Azam & Srivastava, 2020;Ban et al, 2020;Baojuan et al, 2020;Noel et al, 2020).…”