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

社会相关性：为人口提供充足的优质水将是近期的重大挑战之一。土地使用和气候变化加剧了这一问题。我们只有有限的可能性来创造新的水或季节性地将水库中的水转移到短缺时期。明智地使用和管理水资源似乎是缓解这一状况的最有希望的手段。因此，数值模型已被用于湖泊：然而，水属性的实施仍然依赖于海洋假设。因此，在接近最大密度温度（即接近4°C）的湖泊深水中模拟流动是有缺陷的或与现实完全脱节。我们假设在数值模型中加入温压性可以解决这个问题，温压效应也得到了适当的反映。我们对沃茨的物理性质有了更好的了解。数值湖泊模型可以大大改进。 科学挑战：温压性控制着温带和亚极地气候区深湖的再循环。虽然这一主题最近在海洋学中引起了兴趣，但深湖的特征还没有得到适当的处理。根据定义，当温压效应占主导地位时，势密度的方便性质就丧失了。这使得稳定性考虑难以显示。 然而，我们相信，温压效应的描述可以显着改善。我们建议从基本的热力学方法稳定性的考虑，以简约的建模，并将完成这个研究计划的实施适当列入数值模型中的温压性，以证明在一些突出的情况下的效果。我们相信，通过我们共同的能力，我们可以找到新的方法来理解和交流温压效应。从我们的经验，我们找到有效的数值方法来妥善处理的主题，以实现和演示在一些深湖温压效应。我们将使用DELTARES的DELFT3D模型进行数值模拟。我们希望该项目为未来富有成效的合作开辟前景。

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.