Glacio-Nival Regime Creates Complex Relationships between Discharge and Climatic Trends of Zackenberg River, Greenland (1996–2019)

• Published in: Climate
• Main Authors: Karlijn Ploeg, Fabian Seemann, Ann-Kathrin Wild, Qiong Zhang
• Format: Article in Journal/Newspaper
• Language: English
• Published: MDPI AG 2021
• Subjects: arctic drainage; proglacial river; hydroclimatology; mountain hydrology; snowmelt; GLOF; Science; Q; Arctic; Greenland; Ice cap; Ice Sheet; Zackenberg
• Online Access: https://doi.org/10.3390/cli9040059; https://doaj.org/article/6d85ee39f2dc4b259feb1087cd8cc7f5

Arctic environments experience rapid climatic changes as air temperatures are rising and precipitation is increasing. Rivers are key elements in these regions since they drain vast land areas and thereby reflect various climatic signals. Zackenberg River in northeast Greenland provides a unique opportunity to study climatic influences on discharge, as the river is not connected to the Greenland ice sheet. The study aims to explain discharge patterns between 1996 and 2019 and analyse the discharge for correlations to variations in air temperature and both solid and liquid precipitation. The results reveal no trend in the annual discharge. A lengthening of the discharge period is characterised by a later freeze-up and extreme discharge peaks are observed almost yearly between 2005 and 2017. A positive correlation exists between the length of the discharge period and the Thawing Degree Days ( <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>r</mi><mo>=</mo><mn>0.52</mn><mo>,</mo><mi>p</mi><mo><</mo><mn>0.01</mn></mrow></semantics></math> ), and between the total annual discharge and the annual maximum snow depth ( <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mi>r</mi><mo>=</mo><mn>0.48</mn><mo>,</mo><mi>p</mi><mo>=</mo><mn>0.02</mn></mrow></semantics></math> ). Thereby, snowmelt provides the main source of discharge in the first part of the runoff season. However, the influence of precipitation on discharge could not be fully identified, because of uncertainties in the data and possible delays in the hydrological system. This calls for further studies on the relationship between discharge and precipitation. The discharge patterns are also influenced by meltwater from the A.P. Olsen ice cap and an ...