Extreme Climatic Events in the Oceans: Towards a mechanistic understanding of ecosystem impacts and resilience

在有记录的人类历史上，过去十年从未发生过如此多的极端气候事件，而人为气候变化现在被认为是这一趋势的主要贡献者。干旱、洪水、气旋、寒流和热浪都通过地球气候系统联系在一起，可能对陆地和海洋产生重大的生态和社会经济影响。尽管人们越来越认识到离散的极端事件在决定生态系统结构方面的重要性，但绝大多数知识来自陆地研究，尽管海洋生态系统在大多数人的生活中在文化、社会和经济方面发挥着核心作用。海洋生态系统提供了无数生态产品和服务，包括营养循环、食物和其他资源、生物海岸防御和气候调节，所有这些都具有重大的社会经济价值。珊瑚礁、海草草甸和温带海藻森林在娱乐、渔业活动、海岸防御和生物多样性产生的资本方面特别宝贵，每年为全球经济贡献数万亿英镑。仅在英国，海洋生物多样性的估计直接经济价值每年就超过200亿GB。在海洋环境研究中，人们对海洋酸化和最近的塑料污染给予了很大关注，但有一个强有力的论点表明，极端变暖事件(即“海洋热浪”)对生态系统构成了更大的风险。仅在过去十年，MHW就破坏了整个生态系统，严重影响了渔业、水产养殖、食物网和碳循环。近几十年来，由于人为气候变化，MHW的发生频率和持续时间显著增加，预计在整个21世纪还将增加。尽管MHW在构建生态系统方面的重要性毋庸置疑，但我们目前对其影响的了解仍然很差。对MHW反应的了解仅源于几个事件，例如1998年的厄尔尼诺事件、2003年的地中海MHW和2011年西澳大利亚附近的变暖事件。例如，2011年西澳大利亚州近海的MHW导致了热带-温带过渡带底栖生态系统结构的重大转变，导致形成冷水栖息地的物种普遍死亡。该项目将解决海洋气候变化生态学方面的关键知识空白问题。它将综合现有关于大规模杀伤性武器的生态反应的信息，并使用一种新的分析方法来对其影响进行全球范围的分析。该项目还将进行一系列实验和调查，以检查具有不同物理属性的MHW如何影响关键生物体和过程。最后，将基于物理和生态建模技术对MHW的未来模式和影响进行预测。该项目将大大促进对极端气候事件对全球海洋的影响的了解，并将与气候变化的缓解和适应直接相关，因为社会必须保护宝贵的沿海海洋生态系统，使其免受未来几十年气候压力的增加。

Never before in recorded human history have there been as many extreme climatic events as in the past decade, and anthropogenic climate change is now recognised as a major contributor to this trend. Droughts, floods, cyclones, cold snaps and heat waves are all linked through Earth's climate systems and can have significant ecological and socio-economic impacts on land and in the oceans. Despite growing appreciation of the importance of discrete, extreme events in determining ecosystem structure the vast majority of knowledge stems from terrestrial research, even though marine ecosystems play a central role culturally, socially and economically in the lives of most people. Marine ecosystems provide a myriad of ecological goods and services, including nutrient cycling, food and other resources, biogenic coastal defence and climate regulation, all of which have substantial socioeconomic value. Coral reefs, seagrass meadows and temperate kelp forests are particularly valuable in terms of capital generated from recreation, fishing activities, coastal defence and biodiversity, and contribute trillions of pounds to the global economy each year. In the UK alone, the estimated direct economic value of marine biodiversity exceeds £20 billion per year. In marine environmental research, much attention has been given to ocean acidification and, more recently, plastic pollution, yet there is a strong argument to suggest that extreme warming events (i.e. 'marine heatwaves' (MHWs)) pose an even greater risk to ecosystems. In the past decade alone, MHWs have devastated entire ecosystems and severely affected fisheries, aquaculture, food webs and carbon cycling. The frequency and duration of MHWs has increased significantly in recent decades and is predicted to increase throughout the 21st Century, as a consequence of anthropogenic climate change. Despite the unequivocal importance of MHWs in structuring ecosystems, our current understanding of their impacts remains poor. Knowledge of responses to MHWs stems from only a few events, such as the 1998 El Niño episode, the Mediterranean MHW of 2003 and the 2011 warming event off Western Australia. The 2011 MHW off Western Australia, for example, resulted in major shifts in benthic ecosystem structure in a tropical-temperate transition zone, by causing widespread mortality of cool-water habitat forming species. This project will address critical knowledge gaps in marine climate change ecology. It will synthesise existing information on ecological responses to MHWs and use a novel analytical approach to conduct a global-scale analysis of their impacts. The project will also carry out a range of experiments and surveys to examine how key organisms and processes are affected by MHWs with differing physical attributes. Finally, predictions of future patterns and impacts of MHWs will be made, based on physical and ecological modelling techniques. This project will significantly advance understanding of the impacts of extreme climatic events in the global ocean and will be of direct relevant to climate change mitigation and adaptation, as society must safeguard valuable coastal marine ecosystems against increased climatic stress in the coming decades.