Recent and Ongoing Changes in the High-latitude Atlantic (ROCHA)

北大西洋高纬度海域目前正在经历与人为气候变化有关的重大变化（海洋变暖、冰盖减少和大气热损失大幅增加）。这些海洋，特别是拉布拉多海、Irminger海和北欧海是全球海洋环流的关键北方地点。在最近的研究中，我们开发了一个温度数据集跨越2004-2008年的拉布拉多和Irminger海从阿尔戈浮标和海洋哺乳动物传感器（MMBS）的数据。我们对这个数据集的分析表明，在广泛使用的国际数据集中，海洋边界流温度的估计值过高，最高可达2摄氏度。识别这种暖偏差对于该地区气候变化影响的观测和基于模式的研究至关重要。在我们早期的研究中，我们被限制在一个小的空间域和一个有限的时间段，截止到2008年。然而，由于Argo浮标计划的扩展，新的MMBS数据的可用性以及首次纳入滑翔机和船舶测量，我们现在可以开发一个新的增强数据集。具体而言，我们现在能够扩展空间域，包括北欧海（从而包括所有北大西洋密集水形成区）和时间段到2003-2012年（允许在过去十年的关键变化进行全面检查）。此外，现在可以将盐度和温度包括在内，从而使人们能够对不断变化的淡水含量和海洋密度有新的认识。我们建议开发一个世界领先的新的T和S数据集，涵盖拉布拉多，Irminger和北欧海，这将是第一个采用该地区所有可用观测数据的数据集。此外，我们将使用新的数据集。）确定LIN海域最近和正在发生的变化，以及B.）严格评估NEMO海洋模型（NERC海洋旗舰计算机模型），从而确定在多大程度上可以依赖它来提供这一领域的进一步见解。拟议的研究是我们以前研究的一个重大进展，至关重要，因为LIN海被广泛认为是早期检测气候变化影响的关键指标区域。

The high latitude seas of the North Atlantic are currently experiencing major changes (ocean warming, declining ice cover and major increases in heat loss to the atmosphere) associated with man-made climate change. These seas, specifically the Labrador, Irminger and Nordic (LIN) Seas are the key northern sites for the global ocean circulation. In recent research, we developed a temperature dataset spanning 2004-2008 for the Labrador and Irminger Seas from Argo float and Marine Mammal-Borne Sensor (MMBS) data. Our analysis of this dataset revealed that estimates of ocean boundary current temperatures in widely used international datasets are too warm by up to 2 deg Centigrade. Identification of such warm biases is critical to both observation and model-based studies of climate change impacts in this region. In our earlier study, we were restricted to a small spatial domain and a limited time period ending in 2008. However, as a result of expansion of the Argo float programme, new availability of additional MMBS data and the inclusion for the first time of glider and ship based measurements, we are now in position to develop a new much-enhanced dataset. Specifically, we are now able to extend the spatial domain to include the Nordic Seas (thereby including all North Atlantic dense water formation regions) and the time period to 2003-2012 (allowing a full examination of key changes in the past decade). In addition, it is now possible to include salinity as well as temperature, thereby enabling new insights into changing freshwater content and ocean density. We propose to develop a world-leading new T and S dataset covering the Labrador, Irminger and Nordic Seas, which will be the first to employ all available observations across this region. Furthermore, we will use the new dataset to a.) determine recent and ongoing changes in the LIN Seas, and b.) critically evaluate the NEMO ocean model (NERCs flagship computer model of the ocean) and thus identify the extent to which it can be relied upon to provide further insights in this area. The proposed research is a major advance on our previous study and is vital as the LIN Seas are widely recognised to be a key indicator region for the early detection of climate change impacts.