SWIPS (Shallow Water Ice Profiling Sonar)：Peace河浅水冰剖面声纳数据分析及其对冰冻河流中潜冰和原位锚冰生长作用的影响
Abstract
Peace River SWIPS (Shallow Water Ice Profiling Sonar) data were analyzed to quantify the roles of frazil ice and riverbed anchor ice grown in situ during the initial buildup of a seasonal ice cover. Data were derived through quasi-continuous monitoring of frazil parameters throughout the water column, providing direct and indirect measures of anchor ice volume and mass growth rates. Analyses utilized water level and air and water temperature information in conjunction with acoustic volume backscattering coefficient data to track and interpret spatial and temporal changes in riverbed and water column ice. Interest focused on four frazil intervals characterized by anomalously low levels of frazil content (relative to simulations with an anchor-icefree river ice model) as distinguished by two strikingly different types of time dependences. A simple physical model was proposed to quantitatively account for discrepancies between measured and simulated results in terms of the pronounced dominance of anchor ice as an initial source of river ice volume and mass. The distinctive differences in temporally variable water column frazil content are attributed, in this model, to corresponding differences in the stabilities of riverbed anchor ice layers against detachment and buoyancydriven movement to the river surface. In accord with earlier observations, the stability of in situ grown riverbed ice layers appears to be inversely proportional to cooling rates. The strength of the coupling between the two studied ice species was shown to be strong enough to detect changes in the anchor ice constituent from variations in water column frazil content.
摘要：
对Peace河SWIPS（浅水冰剖面声纳）数据进行了分析，以量化在季节性冰盖初始形成期间原位生长的潜冰和河床锚冰的作用。数据是通过对整个水柱的潜冰参数进行准连续监测得出的，提供了锚冰体积和质量增长率的直接和间接测量。分析利用水位、空气和水温信息以及声体积后向散射系数数据来跟踪和解释河床和水柱冰的空间和时间变化。兴趣集中在四个潜冰间隔上，其特征是潜冰含量异常低（相对于锚无冰河冰模型的模拟），这两个间隔的时间依赖性截然不同。提出了一种简单的物理模型，定量解释了测量结果和模拟结果之间的差异，即锚冰作为河流冰量和质量的初始来源具有明显的优势。在该模型中，时变水柱潜冰含量的显著差异归因于河床锚冰层对分离和浮力驱动的河流表面运动的稳定性的相应差异。根据早期的观察，原位生长的河床冰层的稳定性似乎与冷却速率成反比。两种研究冰种之间的耦合强度被证明足够强，可以从水柱潜冰含量的变化中检测到锚冰成分的变化。
关键词：IPS冰剖面仪，SWIPS浅水冰剖面仪，冰声学回声探测，后向散射，ASL冰剖面声呐
