Thermobaricity: Pressure effects on temperature stratification and circulation in lakes - PONTEM

温压：压力对湖泊温度分层和环流的影响 - PONTEM

• 批准号: 524611035
• 负责人: Privatdozent Dr. Bertram Boehrer
• 金额: --
• 依托单位: Department Seenforschung
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/524611035?language=en
• 关键词: Thermobaricity; Pressure; effects; temperature; stratification

Societal Relevance: Providing the population with sufficient good quality water will be one of the great challenges in near future. Land use and climate change exacerbate this problem. We have only limited possibilities to create new water or transfer water in reservoirs seasonally to periods of shortage. Wise use and management of water resources appear as the most promising tools to alleviate the situation. Hence, numerical models have been adopted for lakes: the implementation of water properties however is still tied to ocean assumptions. As a consequence, simulated flows in the deep water of lakes close to temperature of maximum density (i.e. near 4°C) are flawed or entirely disconnected from reality. We hypothesize that an inclusion of thermobaricity in numerical models solves this issue and thermobaric effects are properly reflected. We have much better knowledge of the physical properties of lake waters. Numerical lake models could be substantially improved. Scientific Challenge: Thermobaricity is controlling recirculation in deep lakes in the temperate and subpolar climate zone. Though the topic has gained interest recently in oceanography, the features in deep lakes have not been properly dealt with. By definition, the convenient property of potential density is lost, when thermobaric effects are dominant. This makes stability considerations difficult to display. However, we are convinced that the description of thermobaric effects can significantly be improved. We propose to start from basics of thermodynamic approaches to stability considerations to parsimonious modelling and will complete this research programme by the implementation of a proper inclusion of thermobaricity in numerical models to demonstrate the effects in some prominent cases. We are convinced that with our joined competences we find new approaches to understand and communicate thermobaric effects. From our experience we find effective numerical approaches to properly deal with the topic to implement and demonstrate thermobaric effects in some deep lakes. We will use the model DELFT3D by DELTARES for numerical simulations. We expect that this project opens the perspective of future fruitful collaboration.

社会相关性：为人们提供充足的优质水将是不久的将来面临的巨大挑战之一。土地利用和气候变化加剧了这一问题。我们在短缺时期创造新水或季节性调水的可能性有限。明智地使用和管理水资源似乎是缓解这种情况最有希望的工具。因此，湖泊采用了数值模型：然而，水特性的实施仍然与海洋假设相关。因此，接近最大密度温度（即接近 4°C）的湖泊深水中的模拟水流是有缺陷的或完全与现实脱节。我们假设在数值模型中包含温压可以解决这个问题，并且温压效应得到正确反映。我们对湖水的物理特性有了更多的了解。湖泊数值模型可以得到大幅改进。 科学挑战：温压正在控制温带和亚极地气候区深湖的再循环。尽管这个话题最近在海洋学中引起了人们的兴趣，但深湖的特征尚未得到适当的处理。根据定义，当温压效应占主导地位时，势密度的便利特性就会消失。这使得稳定性考虑因素难以显示。 然而，我们相信温压效应的描述可以显着改进。我们建议从热力学方法的基础知识开始，到稳定性考虑到简约建模，并将通过在数值模型中适当包含温压来完成这项研究计划，以证明在一些突出情况下的效果。我们相信，通过我们的联合能力，我们找到了理解和传达温压效应的新方法。根据我们的经验，我们找到了有效的数值方法来正确处理该主题，以在一些深湖中实施和演示温压效应。我们将使用 DELTARES 的 DELFT3D 模型进行数值模拟。我们期望这个项目为未来富有成效的合作开辟前景。