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

在有记录的人类历史中，从来没有像过去十年那样发生过如此多的极端气候事件，而人为气候变化是造成这一趋势的主要因素。干旱、洪水、风暴和热浪都通过地球的气候系统联系在一起，并可能对陆地和海洋产生重大的生态和社会经济影响。尽管人们日益认识到极端气候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发挥着文化、社会和经济方面的核心作用。海洋生态系统提供了无数的生态产品和服务，包括养分循环、食物和其他资源、生物海防和气候调节，所有这些都具有重大的社会经济价值。珊瑚礁、海草草甸和海带森林在娱乐、渔业活动、海防和生物多样性方面产生的资本尤其宝贵，每年为全球经济贡献数万亿英镑。仅在英国，海洋生物多样性每年的直接经济价值估计就超过200亿英镑。在海洋环境研究中，人们对海洋酸化以及最近的塑料污染给予了很大的关注，然而，有强有力的论据表明，极端变暖事件（即气候变暖）可能导致海洋酸化。“海洋热浪”（MHWs）对生态系统构成了更大的风险。仅在过去十年中，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，大热浪的频率和持续时间显著增加，并且由于人为气候变化，预计在整个21世纪还会增加。尽管mhw在构建生态系统中具有明确的重要性，但我们目前对其影响的理解仍然很差。对高强度热浪反应的认识仅来自少数事件，如1998年的厄尔尼诺Niño事件、2003年的地中海高强度热浪和2011年西澳大利亚近海的变暖事件。例如，2011年西澳大利亚近海的MHW导致了热带-温带过渡带底栖生物生态系统结构的重大变化，造成了冷水栖息地形成物种的广泛死亡。该项目将填补海洋气候变化生态学方面的关键知识空白。它将综合现有的关于mhw生态反应的信息，并使用一种新的分析方法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，以研究具有不同物理属性的mhw如何影响关键生物体和过程。最后，将根据物理和生态模拟技术，对未来的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影响的了解，并将与减缓和适应气候变化直接相关，因为社会必须在未来几十年保护宝贵的沿海海洋生态系统免受日益增加的气候压力。除了重大的学术影响外，该研究项目还将产生相当广泛的社会影响。这些发现将被转化为国家（例如MCCIP、CEFAS）和国际（例如IPCC、ICES）层面的政策。对具有重要商业价值的物种和生境的研究将与水产养殖业和渔业直接相关。关于气候变化-碳循环反馈的工作对从事蓝碳和减缓气候变化工作的人（例如自然保护联盟、蓝碳倡议）具有战略意义。在整个项目中，沿海海洋生态系统的重要性和气候变化压力带来的威胁将通过各种渠道广泛传达给学术界、工业界、政策制定者和更广泛的公众。

Never before in recorded human history have there been as many extreme climatic events as in the past decade, with anthropogenic climate change the major contributor to this trend. Droughts, floods, storms, and heatwaves 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 extreme climatic 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 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. Aside from significant academic impact, the research project will have considerable wider societal impact. The findings will be translated and fed into policy at both the national (e.g. MCCIP, CEFAS) and international (e.g. IPCC, ICES) level. Research on commercially-important species and habitats will be directly relevant for the aquaculture and fishing industries. Work on climate change-carbon cycle feedbacks will be of strategic significance to those working on Blue Carbon and climate change mitigation (e.g. IUCN, Blue Carbon Initiative). Throughout the project the importance of coastal marine ecosystems and threats posed by climate change stressors will be communicated widely to academics, industry, policy-makers and the wider public through a variety of channels.