Conference Agenda

It is presented in this paper the main scientific objectives and some progresses of ESA-MOST China Dragon 6 Cooperation Program “Synergistic Monitoring and Prediction of Ocean Dynamic Environment from Multi-satellite Data (ID. 95315)” including: (1) assimilation studies of wind, waves and sea level in the context of hurricanes forecasts; (2) the influence of swell on the studies of coastal extremes; (3) studies of vortex Rossby waves, asymmetric TC structures, rain bands, and sub-scale circulations by using high spatial resolution ocean wind data; (4) analysis of relationship between the above internal dynamical processes and TC intensity changes; (5) consistent analysis and prediction of winds, waves and storm surges in the context of hurricanes; and (6) consistent monitoring and prediction of ocean surface current and internal waves using multi-source satellite data.

Atlantic Water (AW) transported to the Arctic Ocean through the Nordic Seas plays a major role in the global climate system. “Atlantification”, a commonly used term for the increasing influence of AW in the Arctic Ocean,has been found as one of the main climate-change related factors associated with the changes in the Arctic marine ecosystem. For example, Atlantification has been linked to the poleward expansion of temperate phytoplankton and boreal species, and the northward retreat of the Arctic marine ecosystem. Quantifying the role of ocean eddies has been categorized as an important “missing puzzle piece” yet to be studied in detail to better understand Atlantification. The Lofoten Basin (LB) which is the most eddy active region in the Nordic Seas, is a natural laborotory to study the role of the eddies on Atlantification. Located along the advective path of AW in the Nordic Seas, a main feature of the LB circulation is the spinning up off eddies from the Norwegian Atlantic Current, which transports heat to the basin interior and thus mediates the gradual cooling of the slope current on its way toward the Arctic.

The overall objective of the project LoWa (Lofoten Basin eddies and its impact on Atlantic Water heat transport towards the Arctic) is to quantify the impact of ocean eddies on the heat transport across the LB affecting Atlantification. To address the overall objective we will use a holistic approach, thanks to the outstanding opportunities offered by the: available satellite constellations with multi-sensor covariability/synergies; in-situ observational networks, gliders and ARGO drifters; co-location of in-situ and remote-sensed data and data driven Artificial Intelligence (AI) methods. Such an approach also extends the possibility to not only investigate ocean mesoscale eddies but also the sub-mesoscale eddies that are even less studied in comparison to mesoscale eddies.

Marine disasters, such as typhoons, algae and phytoplankton blooms pose a serious threat to coastal areas, aquaculture and maritime transportation. As global climate change intensifies, the impact of these marine disasters is becoming increasingly severe. Marine dynamics is the foundation of various marine disaster studies, and the combination of remote sensing monitoring and ocean dynamics is used here to analyze marine disasters.

Through the implementation of the Dragon 5 project 59310, progress has been made in remote sensing data validation, improvement of monitoring technology and enhancement of applications. We used the China’s Ocean Satellites (HY-1 C/D satellites) and the China-France Oceanography Satellite (CFOSAT), combined with Sentinel satellites data from the European Space Agency to carry out three aspects of work:

(1) We carried out remote sensing monitoring research and data application for typical marine ecological disasters in China's offshore areas (such as the green tide of Enteromorpha prolifera and oil spills).

(2) We compared and analyzed the wave spectrum and significant wave height observation results of CFOSAT with buoys, SAR satellite observations and numerical model results, and propose an innovative comparison method.

(3) Based on the geometric relationship between shadow length and satellite observation angle information, we got the iceberg freeboard and its changes in Prydz Bay.

With the approved Dragon Plan Phase 6 project (ID 95549), we plan to further advance the previous Dragon 5 project 59310. More precisely, the new goal is to use multiple satellites such as CFOSAT, FY series, Sentinel series, etc. to jointly monitor marine environmental disasters and better understand relevant marine environmental dynamics. This study will be summarized as follows:

(1) To perform consistency verification on the wind and wave fields provided by CFOSAT and multiple satellites for other missions, such as SWOT (Surface Water and Ocean Topography), HY series, and Sentinel series.

(2) To combine multiple satellite data to monitor and track the development trend of marine environmental disasters such as algae blooms. Meanwhile, multi-scale dynamic analysis will be introduced to characterize the related Wind, Wave and Current Interactions (W2CI) and better understand their potential mechanisms.

(3) To extract ocean surface currents with development of machine learning based optical flow. This technology will be validated using Lagrangian velocities extracted from monitored algal blooms and provide a high spatial resolution velocity field.

In the Dragon Plan Phase 6 project, we have strengthened our team members from both China and France.

The French PI is Dr. François G. Schmitt. His main research area is turbulence, multi-scale data analysis and modelling, and physics-biology coupling in the ocean. The French members are from two units, CNRS-LOG and CNRS-LATMOS. The Chinese PI is Professor Ying Xu. His main research area is ocean satellite processing and applications including waves, sea level rising and marine disasters. The Chinese members are from five units, NSOAS, XMU, NUIST, GDOU and UCAS The professional field of Chinese and French members cover ocean satellite remote sensing and ocean dynamics. The professional background of personnel and previous joint work experience will be very beneficial for the implementation of the Dragon 6 project 95549.