Spatio-temporal Variation Characteristics of Snow Cover and Their Relation with Main Meteorological Elements in the Yellow River Source Region

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  • 1. Lanzhou Regional Climate CentreLanzhou 730020GansuChina
    2. Institute of Arid MeteorologyCMAKey Laboratory of Arid Climatic Change and Reducing Disaster of Gansu ProvinceLanzhou 730020GansuChina

Online published: 2026-04-27

Abstract

In order to explore the response of snow cover to climate conditions under the complex topographybased on composite snow cover products on eight days of MOD10A2daily temperature and precipitation from September 2001 to August 2020 and digital elevation modelDEMin the Yellow-River source regionthe snow cover frequency and percentage was used as an index to study the spatio-temporal variation characteristic of snow cover and their relations with major meteorological elements. The results are as follows:(1Snow was mainly appeared from October to next May in the Yellow-River resource regionand the higher altitudethe greater snow cover percentage and the longer duration. Snow mainly distributed in high mountainous areas. The yearly accumulative process of snow showed a U-shaped at the altitude of 3500 m and belowthe peak appeared in win‐ terwhile that transited to inverted W-shaped above the altitude of 3500 mand the gap between two peaks grad‐ ually reduced with the rising of altitudethe appearing time of the maximum peak shifted from spring to autumn. 2The snow cover percentages on the northern and northerly slopes were more than that on the southern and southerly slopes during the accumulative periodamong the maximum was on the northeastern slopeand the minimum was on the southern slopebut the yearly variation characteristics with inverted W-shaped were similar and synchronous on each slopethe maximum and secondary peaks appeared at the end of October and the early of Aprilrespectively.3Under the background of warming and humidificationthe snow cover percentage dur‐ ing the accumulative period exhibited an overall increasing trend with a rate of about 5. 6% per 10-year in the Yel‐ low-River resource since 2001especially at heights above 4000 m. The significant increase of snow cover area in spring and winter at heights 4000~5000 m contributed greatly to the increase of snow cover percentage during the accumulative period.4The average snow cover percentage first increased and then decreased with the de‐ cline of temperature and the increase of precipitation during the cumulative period in each altitude zone of the Yellow-River sourceand the higher the altitudethe higher the fitting goodness between the two. The consistent increase of precipitation was the key factor contributing to the increase of snow cover percentage in each season of accumulative period since 2001especially the significant increase of precipitation at high altitude areas in spring. Snow was more dependent on precipitation at high altitude areas.

Cite this article

CAI Dihua, SHA Sha, WANG Xing, LIANG Yun, LIU Jingchan, HUANG Tao, ZHAO Hong . Spatio-temporal Variation Characteristics of Snow Cover and Their Relation with Main Meteorological Elements in the Yellow River Source Region[J]. Plateau Meteorology, 0 : 1 . DOI: 10.7522/j.issn.1000-0534.2025.00101

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