DEFIANT: Drivers and Effects of Fluctuations in sea Ice in the ANTarctic

挑战：南极海冰波动的驱动因素和影响

• 批准号: NE/W004720/1
• 负责人: Andrew Shepherd
• 金额: $ 49.17万
• 依托单位: University of Leeds
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2021
• 资助国家: 英国
• 起止时间: 2021 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=NE%2FW004720%2F1
• 关键词: DEFIANT; Drivers; Effects; Fluctuations; sea

Since the start of the industrial revolution the CO2 concentration in the atmosphere has steadily risen. Scientists have confirmed that the recent loss of Arctic sea ice in summer directly follows this rise in human-induced CO2 emissions, reducing from about 7 million km2 of Arctic sea ice in the late 1970s to around 3.5 million km2 in the 2010s.While climate models suggest Antarctic sea ice extent should also reduce in response to rising CO2, satellite observations reveal that during 1979-2015 the opposite was in fact true. The trend in Antarctic sea ice extent has been a small increase of approximately 1.5% per decade. In 2016, however, this increase was abruptly interrupted by a dramatic reduction in sea ice extent that was far outside the previously observed range. Since the extreme event in 2016, Antarctic sea ice extent has almost returned to its pre-2016 values, highlighting the significant variability in Antarctic sea ice conditions that can occur from one year to the next. These variations in sea ice are important to the whole Earth's climate, because they affect the melting of the glacial Antarctic Ice Sheet, and the capture of atmospheric heat and CO2 by the Southern Ocean.The recent extreme swings in Antarctic sea ice extent, and the challenge of accurately predicting, understanding and modelling them, emphasise the need to: (i) increase our knowledge of the processes that drive Antarctic sea ice variations, including extreme events, and (ii) understand the drivers and climate implications of Antarctic sea ice loss over different time-scales, from weeks to decades. To address this knowledge gap requires a significant research programme, one that takes year-round observations, including throughout the harsh Antarctic winter, and is effective in improving the underlying processes in the latest computer climate models.Our project, known as DEFIANT (Drivers and Effects of Fluctuations in sea Ice in the ANTarctic), will embark on one of the most ambitious observational campaigns aimed at understanding Antarctic sea ice variability. Scientific measurements from the German research ship Polarstern, the UK's new polar research ship Sir David Attenborough, the British Antarctic Survey's Rothera research station, aircraft overflights and satellites will work seamlessly together with cutting-edge robotic technologies (including the underwater vehicle Boaty McBoatface and a suite of on-ice buoys) to provide us with comprehensive, year-round measurements of atmosphere, sea ice and ocean. The knowledge gained from these observations will enable our team to develop new ocean and climate models in order to more accurately represent Antarctic sea ice processes.The analysis of these improved models will allow us to better understand the underlying drivers of the sudden decrease in Antarctic sea ice, determine the impact of these extreme events on the global ocean circulation, and forecast the implications for the movements of heat and CO2 through the climate system. By developing new observations, new satellite records, and new models, DEFIANT will deliver a major advance in our understanding of the Antarctic sea ice system and its wider impacts on global climate.

自工业革命开始以来，大气中的二氧化碳集中稳步上升。科学家证实，夏季最近失去的北极海冰直接遵循了人类引起的二氧化碳排放量的增加，从1970年代末的约700万公里毫米2的北极海冰减少到2010年的350万km2。在2010年。气候模型表明，南极海冰还应降低对co2的响应，这表明了在1979年度的响应。南极海冰范围的趋势每十年增加了约1.5％。然而，在2016年，由于海冰范围的急剧减小，这种增加突然中断了，而海冰范围远远超出了先前观察到的范围。自2016年极端事件以来，南极海冰范围几乎恢复了2016年以前的价值，突出了南极海冰条件的显着差异，这可能会发生在一年到下一年。 These variations in sea ice are important to the whole Earth's climate, because they affect the melting of the glacial Antarctic Ice Sheet, and the capture of atmospheric heat and CO2 by the Southern Ocean.The recent extreme swings in Antarctic sea ice extent, and the challenge of accurately predicting, understanding and modelling them, emphasise the need to: (i) increase our knowledge of the processes that drive Antarctic sea ice variations, including extreme events, and (ii) understand the从几周到几十年来，南极海冰损失的驾驶员和气候影响。为了解决这一知识差距，需要一项重要的研究计划，该计划需要全年观察，包括整个艰难的南极冬季，并且有效地改善了最新计算机气候模型中的基础过程。它被称为反抗（驱动力和南极海冰波动的效果），将踏上大量的冰镇，以了解冰镇的行动，这是冰镇的范围。英国新的极地研究船David Attenborough，英国南极调查的Rothera Research Station，飞机飞行和卫星的科学测量，英国新的极地研究船David Attenborough爵士，将与尖端的机器人技术无缝地工作（包括底层车辆的McBoatface，以及一年一度的冰上浮标），并将其全面地衡量。 The knowledge gained from these observations will enable our team to develop new ocean and climate models in order to more accurately represent Antarctic sea ice processes.The analysis of these improved models will allow us to better understand the underlying drivers of the sudden decrease in Antarctic sea ice, determine the impact of these extreme events on the global ocean circulation, and forecast the implications for the movements of heat and CO2 through the climate system.通过开发新的观察结果，新的卫星记录和新模型，Defiant将在我们对南极海冰系统及其对全球气候的更广泛影响方面带来重大进步。