Collaborative Research: A New Method for Understanding Mechanisms of Ice Sheet Demise Using Married General Circulation and Energy-Moisture Balance Model Simulations

提供资金，通过使用包含水同位素的完全耦合的大气-海洋大气环流模式(GCM)和冰盖质量平衡的能量质量平衡模型(EMBM)的成对模拟，采用一种处理冰盖解体的新技术。研究人员将把他们的新技术应用于最后一次冰川消融(2.1万年前)，也就是北半球大冰盖消失的千禧年离散时间片。为了测试GCM结果的技巧，研究人员将使用构建在模型中的示踪剂(即水同位素、宇宙成因同位素、尘埃、海盐和湿地甲烷排放)，在古气候记录中有代理。GCM的结果将迫使EMBM模拟每个时间片的冰盖质量平衡，并将通过将其对冰盖质量损失的预测与从冰川消融期间冰缘变化的地质记录推断的预测进行比较，来检验EMBM的技能。总的研究目标是确定可用于促成冰盖衰变的小规模过程的最低融化水数量。更广泛的影响包括对冰盖消融机制提供更多洞察力的承诺，以及对参与研究的研究生和本科生的支持。

Funding is provided to employ a new technique to address ice sheet disintegration through the use of paired simulations of a fully coupled atmosphere-ocean general circulation model (GCM) containing water isotopes and an energy mass balance model (EMBM) of ice sheet mass balance. The researchers will apply their new technique at discrete millennial time slices to the last deglaciation (21,000 to 10,000 years ago), when large Northern Hemisphere ice sheets disappeared. To test the skill of GCM results, the researchers will use tracers built into the model (i.e., water isotopes, cosmogenic isotopes, dust, sea salt, and wetland methane emissions) for which there are proxies in the paleoclimate record. GCM results will force the EMBM to simulate ice sheet mass balance at each time slice and will test the skill of the EMBM by comparing its predictions of ice sheet mass loss to that inferred from the geologic record of ice margin change during deglaciation. The overall research goal is to determine the minimum amount of melt water available to contribute to the small-scale processes involved in ice sheet decay. The broader impacts include the promise of providing greater insight into the mechanisms of ice sheet decay and the support of graduate and undergraduate students involved in the research.