Controls over Ocean Mesopelagic Interior Carbon Storage (COMICS)

表层海洋是数十亿种被称为浮游植物的微型植物的家园，它们利用阳光和二氧化碳在表层海洋中产生有机物。当它们死亡时，它们会沉入海底，将这些碳带入深海，在那里以数百年至数千年的时间尺度储存，这有助于保持我们今天的气候。它们对我们气候的影响的大小与它们在溶解之前沉入海底的深度有关--它们沉得越深，储存的碳就越多。这种下沉的碳也为生活在海洋深处、黑暗的“黄昏地带”的动物提供了食物。计算机模型可以帮助我们预测未来温室气体排放的变化可能如何改变这个海洋碳库。然而，目前的模型很难做出这些预测。这在一定程度上是因为，直到最近，我们甚至还不能回答这样一个基本问题：生活在黄昏地带的所有动物都有足够的食物吗？但在今年的一项突破中，我们使用了新技术和新理论来证明确实有足够的食物。因此，现在我们可以继续问是什么控制了碳汇的深度。有很多因素可能会影响材料下沉的深度，但目前我们不能确定哪些因素是重要的。在这个项目中，我们将对两个不同的地方进行海洋考察，以测试这些不同的因素如何影响深海的碳储量。我们将测量进入黄昏区域的碳沉降量，以及在该区域内发生的生物过程。然后我们将确定系统是否平衡--换句话说，进去的东西应该再次出来。然后，我们将编写将系统的所有部分链接在一起的方程，并对它们进行分析以使它们变得更加简单。与此同时，我们将测试这些简单的方程是否仍然有用，看看它们是否产生了我们有大量数据的海洋属性的良好全球地图。最后，当我们对我们的新方程运行良好感到高兴时，我们将在计算机模型中使用它们来预测未来海洋中的碳储量。

The surface ocean is home to billions of microscopic plants called phytoplankton which produce organic matter in the surface ocean using sunlight and carbon dioxide. When they die they sink, taking this carbon into the deep ocean, where it is stored on timescales of hundreds to thousands of years, which helps keep our climate the way it is today. The size of the effect they have on our climate is linked to how deep they sink before they dissolve - the deeper they sink, the more carbon is stored. This sinking carbon also provides food to the animals living in the ocean's deep, dark 'twilight zone'. Computer models can help us predict how future changes in greenhouse gas emissions might change this ocean carbon store. Current models however struggle with making these predictions. This is partly because until recently we haven't even beenable to answer the basic question 'Is there enough food for all the animals living in the twilight zone?'. But in a breakthrough this year we used new technology and new theory to show that there is indeed enough food. So now we can move on to asking what controls how deep the carbon sinks. There are lots of factors which might affect how deep the material sinks but at the moment we can't be sure which ones are important. In this project we will make oceanographic expeditions to two different places to test how these different factors affect carbon storage in the deep ocean. We will measure the carbon sinking into the twilight zone and the biological processes going on within it. Then we will determine if the systems are balanced - in other words, what goes in, should come out again. We will then write equations linking all the parts of the system together and analyse them to make them more simple. At the same time we will test whether the simple equations are still useful by seeing if they produce good global maps of ocean properties for which we have lots of data. Finally, when we are happy that our new equations are doing a good job we will use them in a computer model to predict the future store of carbon in the ocean.