Exploring the role of sea ice physics in Arctic climate variability and predictability

最近观测到的北极变化已成为全球气候变化的“典型代表”，特别是因为夏季海冰面积在过去35年中迅速缩小。海冰的退缩导致了跨北极航运的增长，以及从海底开采矿物和化石燃料的计划。近年来，利用新的卫星从太空测量海冰特性，对北极的观测也有所改善。特别是，这些卫星现在提供了对北极冬季海冰厚度的估计。这一进展可以更好地监测海冰状况，并提供了一种新的方法来测试和评估我们对物理的理解以及最新的气候模型模拟。政府间气候变化专门委员会（IPCC）的最新评估得出结论，假设温室气体排放继续增加，到2050年，北极很可能会成为可靠的无冰地区。这种变化将带来巨大的风险和机遇。然而，IPCC所使用的气候模拟常常不能真实地捕捉北极海冰的大尺度特性，如范围、变率和近期趋势。因此，迫切需要改进对北极海冰的模拟，以便更好地了解最近观测到的变化和对未来的可靠预测，以帮助评估风险和机遇，并为有关适应和缓解的重要决策提供信息。此外，越来越需要短期的海冰预报，例如提前几周或几个月，以帮助告知当地社区和航运公司等行业利益相关者。该项目将寻求更好地了解自然天气和气候波动在产生最近北极海冰年度至十年时间尺度变化中的作用。改进气候模式模拟的一个重要因素是更好地反映最新海冰模式中缺失的相关物理过程。这一提议将为海冰模型开发和实施改进的物理学，该模型被包括英国气象局在内的许多国际组织使用。改进后的海冰模型将进一步发展，以改进其对北极气候的模拟，并将测试其提供更可靠的海冰预测的能力。

Recent observed changes in the Arctic have become a 'poster child' for global climatic changes, particularly because the summer sea ice extent has shrunk rapidly over the past 35 years. This retreat of the sea ice has led to growth of trans-Arctic shipping and plans to extract minerals and fossil fuels from the ocean floor. Observations of the Arctic have also improved in recent years with new satellites measuring sea ice properties from space. In particular, these satellites now provide estimates of the sea ice thickness across the Arctic during the winter months. This development allows better monitoring of the state of the sea ice and a new way to test and assess our physical understanding and the latest climate model simulations. The latest assessment of the Intergovernmental Panel on Climate Change (IPCC) concluded that it was likely that the Arctic would become reliably ice-free by 2050 assuming greenhouse gas emissions continue to increase. This change would provide both enormous risks and opportunities.However, the climate simulations used by the IPCC often fail to realistically capture large scale properties of the Arctic sea ice, such as the extent, variability and recent trends. Therefore, there is a key need to improve simulations of Arctic sea ice to provide better understanding of the recent observed changes and credible projections of the future to help assess risks and opportunities and inform important policy decisions about adaptation and mitigation. In addition, there is a growing need for shorter-term sea ice forecasts, such as a few weeks or months ahead, to help inform local communities and industry stakeholders, such as shipping companies. This project will seek to better understand the role of natural weather and climate fluctuations in producing recent Arctic sea ice changes on annual to decadal timescales.One essential ingredient for improving the climate model simulations is to better represent the missing relevant physical processes in the latest sea ice models. This proposal will develop and implement improved physics for the sea ice model, which is used by many international groups, including the Met Office. The enhanced sea ice model will be further developed to improve its simulation of Arctic climate, and its ability to provide more reliable sea ice predictions will also be tested.