ABSTRACT

Atmospherically deposited hoarfrost is probably the least important quantitative component of the hydrosphere, yet in places acts as an important source of water. Although countless studies have investigated the stable isotope composition of virtually all other components of the global hydrosphere, little is known on its stable isotope composition. We addressed this gap in knowledge by investigating the stable isotope composition of hoarfrost and precipitation in the Southern Carpathian Mountains (East-Central Europe) in relation with the local and regional meteorological parameters and hoarfrost characteristics. Hoarfrost and precipitation were collected at the Țarcu Peak Weather Station (2180 m a.s.l.) between December 2018 and February 2019. The main sources of moisture (as indicated by high deuterium excess values) were the Black (and possibly Caspian) Sea as well as the terrestrial sources in Eastern Europe and Western Asia. Hoarfrost was deposited during periods of intense wind, with δ¹⁸O and δ²H being strongly correlated with air temperature. No correlation has been found between the intensity of hoarfrost deposition and its stable isotope characteristics. Our data indicates that the δ¹⁸O values of hoarfrost deposits faithfully record air temperature variability during deposition, while the d-excess parameter records conditions at the moisture sources.

摘要

大气沉积的白霜可能是水圈中最不重要的数量成分，但在某些地方却是重要的水源。尽管无数研究调查了全球水圈几乎所有其他成分的稳定同位素组成，但对其稳定同位素组成知之甚少。我们通过研究南喀尔巴阡山脉（东中欧）的白霜和降水的稳定同位素组成与当地和区域气象参数和白霜特征的关系，解决了这一知识差距。2018 年 12 月至 2019 年 2 月期间，在 Țarcu Peak 气象站 (2180 m asl) 收集了白霜和降水。水分的主要来源（如高氘过量值所示）是黑海（可能还有里海）以及东欧和西亚的陆地来源。白霜是在强风期间沉积的，δ ¹⁸ O 和δ ² H 与气温密切相关。尚未发现白霜沉积强度与其稳定同位素特征之间存在相关性。我们的数据表明，白霜沉积物的δ ¹⁸ O 值忠实地记录了沉积过程中的气温变化，而d -excess 参数记录了水分源的条件。