Resolving Biological carbon Export in the Labrador Sea (ReBELS)

海洋表层是数十亿微生物类浮游植物的家园，它们利用阳光和二氧化碳在海洋表层产生有机物。当它们死亡时，它们下沉并将这些碳带入深海，在那里以数百年到数千年的时间尺度储存起来。这种储存有助于保持我们今天的气候。这种生物二氧化碳吸收和储存在深海的过程被称为“生物碳泵”，为了了解我们的气候在不久的将来会如何变化，我们需要了解是什么控制了这一过程。直到最近，人们还认为生物碳泵的工作几乎独立于海洋中的混合过程，比如风暴、冬季或蜿蜒的洋流。然而，最近的研究表明，这些物理过程可能对生物碳泵非常重要，为碳到达深海提供了直接途径，并且可以向深度贡献与死亡物质沉没一样多的碳。因此，我们迫切需要了解生物和物理过程如何相互作用，将有机物输送到深海。有两个原因可以解释这种明显的疏忽：物理和生物海洋学家经常独立工作，因此跨学科的过程可能会被忽视。此外，这些过程对海洋碳储存产生最大影响的地点和时间是恶劣的环境，海浪和强风使得在船上工作几乎是不可能的。rebel是一个令人兴奋的项目，它将物理和生物海洋学家聚集在一起，在生物碳泵上紧密合作。为了克服后勤方面的挑战，“反叛军”将利用最新的技术发展，使用最先进的海洋自主机器人，在我们无法用船只进行采样的时候，这些机器人将能够对海洋进行采样。我们的研究地点是西北大西洋的拉布拉多海。在那里，有机碳在深海中停留的时间比世界上任何其他地方都要长得多（大约1000年）。此外，拉布拉多海已被确定为气候的一个非常重要的位置，因为它受到温度上升和冰融化的强烈影响。利用自主技术，我们将测量一整年的生物碳泵，并通过不同的生物和物理过程量化碳运输和碳储存。为此，我们将测量整个水柱中有机物颗粒的分布，并确定它们是在下沉还是被海洋混合输送。然后，我们将使用可以在更大尺度上确定的代理（例如通过卫星）将我们的结果扩展到整个西北大西洋。最后，我们将与建模人员合作，在预测未来气候时纳入这些重要过程。

The surface ocean is home to billions of microscopic plant-like phytoplankton which produce organic matter in the surface ocean using sunlight and carbon dioxide. When they die, they sink and take this carbon into the deep ocean, where it is stored on timescales of hundreds to thousands of years. This storage helps to keep our climate the way it is today. This process of biological CO2 uptake and storage in the deep ocean is called the 'biological carbon pump' and, in order to understand how our climate will change in the near future, we need to understand what controls this process. Until fairly recently, the biological carbon pump was thought to work almost independently from the mixing processes that occur in the oceans, such as during storms, winter or by meandering ocean currents. However, recent work suggested that these physical processes may be very important for the biological carbon pump, providing a direct pathway for carbon to reach the deep ocean, and can contribute as much carbon to depth as the sinking of dead matter alone. Therefore, we urgently need to understand how the biological and physical processes interact to transport organic matter into the deep ocean.Two reasons explain this clear oversight: Physical and biological oceanographers often work independently, so that crossdisciplinary processes can get overlooked. In addition, the location where, and times when, these processes have the most dramatic effect on ocean carbon storage are hostile environments to work in, with very high waves and strong winds that make working from ships nearly impossible. ReBELS is an exciting programme that will bring together physical and biological oceanographers to closely work together on the biological carbon pump. To overcome the logistical challenges, ReBELS will take advantage of the recent developments in technology, using state-of-the-art marine autonomous robots that will be able to sample the ocean at times where we cannot do so with ships. Our study site will be the Labrador Sea in the Northwest Atlantic. There, organic carbon stays in the deep ocean much longer than anywhere else in the world (>1000 years). Moreover, the Labrador Sea has been identified as a very important location for the climate, as it is strongly affected by increasing temperatures and melting ice.Using autonomous technology, we will measure the biological carbon pump over the course of an entire year, and quantify carbon transport and carbon storage through the different biological and physical processes. To do so, we will measure the distribution of organic matter particles throughout the water column and determine whether they are sinking or being transported by ocean mixing. We will then extend our results to the entire Northwest Atlantic using proxies that can be determined on larger scales (for example from satellites). Finally, we will work with modellers to include these important processes when predicting climate in the future.