Understanding Heat-transfer Regimes in Past, Present and Future Climates

了解过去、现在和未来气候下的传热机制

• 批准号: 2033467
• 负责人: Tiffany Shaw
• 金额: $ 57.44万
• 依托单位: University of Chicago
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-02-01 至 2024-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2033467&HistoricalAwards=false
• 关键词: Understanding; Heat; transfer; Regimes; Past

The Earth's climate is a product of heat transfer, as the warming effect of heat energy gains, including the latent heat released in precipitation, must over time be balanced by equal heat losses to achieve a persistent climate state in any given region. An atmospheric column can transfer heat energy through its top and bottom by radiation, for instance when it cools by emitting infrared radiation to space, and by evaporation and thermal conduction at the Earth's surface. Lateral heat transfer is also critical, as in the tropics the Earth receives more energy from the sun than it radiates back to space and the opposite is true near the poles. Thus the tropics must export heat energy to the poles to balance the budgets of both regions. Work under this award seeks to understand atmospheric heat transfer in low, middle, and high latitudes, considering both changes in heat transfer over the the seasonal cycle and differences in heat transfer between warmer and colder climates. For example simulations of modern climate show strong seasonal variations in latitudinal heat balances, with radiation largely balancing local evaporation and surface heat conduction in the middle latitudes of the Northern Hemisphere in summer, while lateral heat transfer is more prominent in other seasons. The situation is quite different in simulations of the "snowball earth" climate, where lateral transfer is prominent throughout the year over most of the globe. The underlying mechanisms that determine atmospheric heat balances in different climates, and drive changes in heat balances during transitions between climate states, are explored through analysis of existing simulations and through novel simulations using a variety of model configurations.Heat transport plays an essential role in maintaining Earth's climate, and research on the topic has societal value given the need to better understand how the climate system works and how it is likely to change under the influence of greenhouse gas increases and changes in aerosol pollution. The project also provides support and training for a graduate student and an undergraduate, the latter recruited through a campus-wide program dedicated to increasing participation of underrepresented minorities in scientific research.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

地球的气候是热传递的产物，因为随着时间的推移，包括降水中释放的潜热在内的热能增加的变暖效应必须通过相等的热损失来平衡，以在任何特定地区实现持续的气候状态。大气柱可以通过辐射通过其顶部和底部传递热能，例如当它通过向太空发射红外辐射而冷却时，以及通过地球表面的蒸发和热传导。 横向热传递也是至关重要的，因为在热带地区，地球从太阳接收的能量比辐射回太空的能量要多，而在两极地区则相反。因此，热带地区必须向两极输出热能，以平衡两个地区的收支。 该奖项的工作旨在了解低，中，高纬度地区的大气热传递，考虑热传递在季节周期中的变化以及温暖和寒冷气候之间的热传递差异。例如，对现代气候的模拟显示，纬度热平衡存在很强的季节性变化，在夏季，辐射在很大程度上平衡了北方中纬度地区的局部蒸发和地表热传导，而在其他季节，横向热传递更为突出。 在模拟“雪球地球”气候时，情况完全不同，在地球仪的大部分地区，横向转移全年都很突出。 通过对现有模拟的分析和使用各种模式配置的新模拟，探讨了决定不同气候条件下大气热平衡的基本机制，以及在气候状态之间转换期间驱动热平衡变化的机制。热传输在维持地球气候方面起着至关重要的作用，鉴于需要更好地了解气候系统如何运作，以及在温室气体增加和气溶胶污染变化的影响下气候系统可能如何变化，关于这一专题的研究具有社会价值。该项目还为一名研究生和一名本科生提供支持和培训，后者是通过一个致力于提高代表性不足的少数民族在科学研究中的参与度的校园范围内的计划招募的。该奖项反映了NSF的法定使命，并通过使用基金会的智力价值和更广泛的影响审查标准进行评估，被认为值得支持。

项目成果

Quantifying Energy Balance Regimes in the Modern Climate, Their Link to Lapse Rate Regimes, and Their Response to Warming

量化现代气候中的能量平衡机制、它们与失效率机制的联系以及它们对变暖的反应

• DOI: 10.1175/jcli-d-21-0440.1
• 发表时间: 2022
• 期刊: Journal of Climate
• 影响因子: 4.9

Why Are Mountaintops Cold? The Transition of Surface Lapse Rate on Dry Planets

山顶为何寒冷？

• DOI: 10.1029/2023gl106683
• 发表时间: 2023
• 期刊: Geophysical Research Letters
• 影响因子: 5.2
• 作者: Fan, Bowen;Jansen, Malte F.;Mischna, Michael A.;Kite, Edwin S.
• 通讯作者: Kite, Edwin S.