Comparative Analysis of Deep Argo in Situ Data With a Novel Extrapolation Method Illustration of Anomalies

摘要

The first worldwide array observing global oceans in near real–time is made possible by the Argo Program. The need for this particular activity was compelled by requirement of weather–related ocean data desired by the oceanographic researchers around the world. During the late twentieth century, this idea regarding an array for in–situ Geostrophic Oceanography i.e. Argo program was initially suggested by researchers from Japan as well as the United States. To execute such an array, deployment of regional arrays initiated in 1999. Similarly, deployments on global scale began in 2004. Finally, the entire coverage of global ocean with the help of 3000 active floats was accomplished in 2007 to the depths of 2000 dbar. In this regard, almost half of the buoys are being provided by US Argo in throughout international program. Furthermore, US Argo is being reinforced by the National Oceanic and Atmospheric Administration. In addition, it is being supported by the Navy via the National Oceanographic Partnership Program. US Argo is also involved in acting as global leader for the buoy technology, data operation, quality management of data, global collaboration, & making the data available to world researcher and academia community. Nearly 90% of Argo data is available within a day of collection and is absolutely free without any limitation. Moreover, such data is in-situ in nature and quality is according to the research norms. Employment of Argo data ranges from research in oceanography, weather analysis, and academic activities to operational employments for amassing global ocean data and forecasting both seasonal and decadal outcomes. The next joint leap in Argo program is to extend such ocean observation to deeper depths in order to cover the remaining half portion of the global oceans. In this regard, the development of buoys capable of profiling the ocean to depths of 6000 dbar transform the Argo program to cover entire depth on global scale. In addition, such information of deep ocean is vital in analyzing the bottommost–intensified ocean variabilities. By mid of 2014, a workshop titled, “Deep Argo Implementation Workshop”, was conducted in Hobart. During the workshop, Johnson et al. suggested provision of covering $5^{circ} imes oldsymbol{5}^{circ}imes oldsymbol{15}$ -day cycle through a profiling array comprising of 1228 buoys globally. In this regard, the employment of pilot arrays responsible for coverage of varying regions is already under process. Japan and France have developed deep Ninja & Deep Arvor respectively which are designed to dive 4000 m in the ocean. Similarly, United States has developed Solo & Apex which dive to a depth of 6000 m in the ocean. This particular study is based on collecting in–situ CTD data from 6000 m deep Argo buoys and then compares this particular data with the ingeniously extrapolated data which is computed by employing a novel way based on the Least Square Method. Furthermore, this CTD data is converted to sound speed profile and then compared again with the extrapolated data which is obtained in the same manner as mentioned earlier. The comparison among the in-situ and extrapolated data exhibits deviation at deeper depths especially after 2500 dbar. These deviations suggest the development of innovative extrapolation algorithms for the rectification of extrapolated values in the deeper oceans. These rectified results are vital for the true analysis of global oceans both temporally and spatially. This particular study offers the foundation for the development of innovative algorithms to correct these extrapolated values in future.