NI: NEW NORMAL - NEar surface Warming in the INdian Ocean and Rainfall Monsoon Anomaly Links

我们这个时代最大的环境挑战之一是理解和预测地球对人为变暖导致的气候系统过度升温的反应。海洋吸收的热量比气候系统的所有其他组成部分都多，捕获了90%以上的多余热量。在全球海洋中，印度洋的变暖速度比其他任何海洋都要快，占海洋热吸收总量的25%。印度洋沿岸国家依赖季风降雨来支持其以农业为基础的经济。具体来说，印度经济的农业部门贡献了约20%的印度GDP (https://www.oecd-ilibrary.org)，但雇佣了约60%的人口（印度经济调查/印度国家抽样调查办公室）。许多科学研究表明，人为变暖正在导致前所未有的极端气候，例如季风降雨的极端气候，气候模型预测，这些事件的频率和强度在未来只会增加，并产生巨大的社会经济影响（例如，2018年印度南部喀拉拉邦的洪水是近100年来最严重的，造成约500人死亡）。科学家绘制了季风周期的总体演变图，并确定孟加拉湾的海表温度（SST）是南亚季风相关降雨的关键驱动因素之一。然而，影响海温和季风降雨的不同过程（例如海洋与大气）的相对重要性尚未得到很好的理解，而且由于极端季风降雨事件与已知的“平均”条件有很大差异，我们还无法预测极端事件何时发生。“新常态”旨在通过将英国和印度研究所在印度洋变暖和季风动力学方面的世界领先权威机构之间的新国际合作结合起来，解决这些悬而未决的问题。他们的目标将是a)量化极端事件期间影响孟加拉湾海温的过程的贡献和途径，b)测试孟加拉湾海温在长达十年的预估时间内的可预测性，特别关注过去记录的极端事件，以及c)为雄心勃勃的未来计划制定路线图，该计划将需要解决气候变化对南亚季风的持续和加速影响。因此，“新常态”将把国际科学界聚集在一起，以理解和预测（可能很快）“新气候常态”，即更多、更极端的气候事件。“新常态”和后续项目的完成对印度的经济发展和福利有直接的应用和好处：更好地预测季风的发生和降雨，这对印度的食品、水和能源部门有直接的好处；改善对季风开始和降雨的预测所带来的好处将是增加产量和减少损失；及时预警潜在的洪水、干旱和热浪将有助于适应和缓解，以确保降低粮食供应和成本的波动性。因此，对季风进行更熟练的预测也将对最贫困人口产生经济和健康上的好处，其形式是减少粮食价格波动和改善营养。除了对农业、水和能源造成影响外，与季风有关的洪水还造成生命和财产损失，印度每年在紧急救济重建基础设施方面的费用高达巨额。例如，据世界银行估计，2018年喀拉拉邦洪灾的恢复成本约为36亿美元。如果有更精确的预测，这一经济成本将大大降低。

One of the biggest environmental challenges of our time is understanding and predicting the Earth's response to excess heating in the climate system due to anthropogenic warming. The ocean absorbs more heat than all other components of the climate system, capturing more than 90% of the excess heat. Of the global oceans, the Indian Ocean is found to be warming faster than any other ocean, accounting for 25% of the total ocean heat uptake. Countries bordering the Indian Ocean are dependent on monsoon rainfall to support their agriculture-based economies. Specifically, the agricultural sector of the Indian economy contributes about 20% of Indian GDP (https://www.oecd-ilibrary.org) but employs around 60% of the population (Economic Survey of India/Indian National Sample Survey Office). Many scientific studies show that anthropogenic warming is leading to unprecedented climate extremes, such as extremes in monsoon rainfall, and climate models project that these events will only increase in frequency and intensity in the future with massive socioeconomic impacts (e.g. 2018 flooding of Kerala in southern India was the worst in nearly 100 years, claiming the lives of ~500 people). Scientists have mapped the general evolution of the monsoon cycle and identified the sea surface temperature (SST) of the Bay of Bengal as one of the key drivers of monsoon-related rainfall in South Asia. However, the relative importance of different processes (e.g. ocean vs atmospheric) influencing the SST and hence monsoon rainfall are not well understood, and because extreme monsoon rainfall events vary significantly from known 'average' conditions, we are not yet able to predict when extreme events will occur. NEW NORMAL aims to address these open questions by bringing together new international collaborations between the UK and world-leading authorities in Indian Ocean warming and monsoon dynamics from Indian Institutes. Their aims will be to a) quantify contributions and pathways of processes that influence Bay of Bengal SST during extreme events, b) test the predictability of the Bay of Bengal SST for lead times up to a decade with particular focus on documented past extreme events, and c) build a roadmap for an ambitious future programme which will be required to address the ongoing and accelerating impacts of climate change on the South Asian monsoon. NEW NORMAL will thus bring together the international scientific community towards understanding and predicting (what may soon be) 'the new climate normal', i.e. more numerous and more extreme climate events.The completion of NEW NORMAL and subsequent programmes has direct applications and benefits for the economic development and welfare of India: Better predictions of monsoon onset and rainfall, which has direct benefit for the food water and energy sectors in India; Benefits due to improved prediction of monsoon onset and rainfall will be in the form of increased yields and reduced losses; timely warning of potential flooding, droughts and heatwaves will allow adaption and mitigation to ensure lower volatility in food availability and cost. Thus, more skilful prediction of the monsoon will also have economic and health benefits for the poorest in the form of reduced fluctuations in food prices and improved nutrition. Aside from the impact on agriculture, water and energy, the monsoon related flooding results in a loss of life and property and costs in India amount to huge sums annually in emergency relief rebuilding infrastructure. For example, the cost of recovery from the 2018 Kerala floods was estimated by the World Bank to be in the region of $3.6bn. This economic cost could be substantially reduced if more skilful forecasts become available.