RAGNARoCC: Radiatively active gases from the North Atlantic Region and Climate Change

我们的目标是了解北大西洋向大气排放的温室气体源和汇的规模有多大，变化有多大。我们的目标是能够描述这些在最近的过去是如何变化的，以及它们在未来将如何在不同的气候情景下发生变化。大部分工作将集中在二氧化碳问题上，我们将对北大西洋碳循环的自然和人为部分进行全面预算，并了解为什么二氧化碳的海气通量在区域、季节和多年之间存在差异。此外，还将对CH4和N2O进行观测，并估计其区域通量。我们将与欧洲和美国的伙伴机构合作，对来自自愿观测船舶网络和固定地点的二氧化碳海气通量进行地面测量。这些将通过对内部碳含量的水文部分的观察来综合。因此，我们将获得对人为碳的吸收、现在的储存和净输送的准确估计，以及北大西洋对大气二氧化碳的自然吸收和释放的可变性。在根据这些观测进行直接估计的同时，将开发这些通量的(大气和海洋类型的)正向和反向模型。主要假设是：(1)可以通过研究大西洋深层碳清单来量化该区域过去对二氧化碳的吸收和变异性，(2)目前观察到的二氧化碳吸收的变异性是气候变化驱动的生物和物理过程的综合结果，主要因素由嵌入气候模型的海洋碳模拟捕捉，(3)这些变化(过去、现在和未来)是气候系统内部的变异性和我们将确定的外部人为强迫作用比例的综合结果。目标是：(1)温室气体进出大西洋通量的业务预报模板，作为国际海洋观测系统的一部分，并与欧洲海洋气候变化框架结合使用；(2)对汇的了解，可用于改进对海洋二氧化碳汇未来如何变化的预测；(3)定量了解过去100年来大西洋对人为二氧化碳的吸收因气候变化而发生变化的方式和原因。

Our object is to understand how large, and how variable, are sources and sinks of greenhouse gases to the atmosphere from the North Atlantic. We aim to be able to describe how these have changed in the recent past and how they will change in the future under different climate scenarios. Most effort will be concentrated on carbon dioxide, and we will deliver a comprehensive budgeting of natural and anthropogenic components of the carbon cycle in the North Atlantic and understanding of why the air-sea fluxes of CO2 vary regionally, seasonally and multi-annually. Observations of CH4 and N2O and estimates of their regional fluxes will additionally be made. We, in collaboration with our partner institutions in Europe and the US, will undertake surface measurements of CO2 air-sea fluxes made from networks of voluntary observing ships and at fixed sites. These will be synthesised with observations from hydrographic sections of the interior carbon content. We will thus obtain accurate estimates of the uptake, present storage, and net transport of anthropogenic carbon, and variability in the natural uptake and release of atmospheric CO2 by the N. Atlantic. In parallel with direct estimates made from these observations, forward and inverse models (of both atmospheric and oceanic kinds) of these fluxes will be developed. The main hypotheses are (1) that past uptake and variability of CO2 in the region can be quantified by examination of the deep carbon inventory in the Atlantic, (2) that the present observed variability in CO2 uptake is due to a combination of biological and physical processes that are driven by climatic variations, the main factors being captured by ocean carbon simulations embedded in climate models, and (3) these variations (past, present and future) are due to a combination of variability internal to the climate system and external anthropogenic forcing - in proportions we will determine. Objectives are (1) a template for operational forecasting of the fluxes of GHGs into and out of the N. Atlantic, to be implemented as part of ICOS and in combination with ECMWF (2) an understanding of that sink that can be used to improve projections of how the ocean CO2 sink will change in the future, and (3) a quantitative understanding of how and why Atlantic Ocean uptake of anthropogenic CO2 has changed as a result of climate change over the last 100 years.