| The variation of hydroclimate in the Qaidam Basin is closely related to the ecological construction and economic development of the region. We analyzed meteorological and hydrological data in Delingha and found that both temperature and precipitation showed a significant upward trend. The warming rate from 1956 to 2022 was 0.45 ℃/10a, and the increase rate of precipitation from 1956 to 2018 was 26.6 mm/10a. Over the past 60 years, winter temperatures have risen the fastest, reaching 0.75 ℃/10a; summer precipitation increased the most, at 17.1 mm/10a. The average discharge of Delingha hydrological station also showed a significant increasing trend, with an increase rate of 1.03 m3/s/10a from 1960 to 2020; the fastest increase rate in summer was 2.89 m3/s/10a. The average discharge is mainly controlled by precipitation, followed by the impact of temperature. The Mann-Kendall test showed that the average discharge experienced a mutation point in 2009. Although the evaporation from 1973 to 1980 was at a high value, the evaporation from 1956 to 2003 showed a downward trend in general, and the average wind speed and sunshine hours were the main factors affecting evaporation. The aridity index (precipitation/evaporation) showed an upward trend, indicating that the climate in Delingha is getting humid. The rising areas of Gahai Lake, Tuosu Lake, and Qinghai Lake, as well as the increase in vegetation coverage in the Qaidam Basin, further confirm the warming and humid characteristics of the climate on the northeast Qinghai-Tibetan Plateau. It is worth paying attention to how the warmer and humid climate on the northeast Qinghai-Tibetan Plateau will further affect the ecological environment evolution of the region. |
