Exploring the origins of waters at Cape Farewell along pathways through the Irminger Sea by Lagrangian Particle Tracking

• Main Author: Ge, Chang (author)
• Other Authors: Katsman, C.A. (mentor), de Vries, S. (graduation committee), Delft University of Technology (degree granting institution)
• Format: Master Thesis
• Language: English
• Published: 2023
• Subjects: AMOC; Climate changes; Lagrangian particle tracking; CMS model; Water origins; Overturning; Greenland; Irminger Basin; Irminger Sea; Cape Farewell; Denmark Strait; East Greenland; Iceland; Labrador Sea; North Atlantic
• Online Access: http://resolver.tudelft.nl/uuid:b856f43a-b39a-460a-94d8-56da386ba6ae

The Atlantic Meridional Overturning Circulation (AMOC) is an important element in the Earth’s Climate System, and it leads to variations in the climate systems, such as heat transformation, carbon dioxide distribution, freshwater distribution, and extreme weather conditions. The dense water formation and export in the North Atlantic contribute to AMOC. Motivated by the aim to understand the strength and processes of AMOC in the Subpolar (SPNA), the water origins and transport routes are explored in this study, based on the inspiration of the previous studies of water pathways in the Labrador Sea. The objective of this study is to investigate the origin of water in the Irminger Sea and the transport routes before arriving at Cape Farewell, the tip of Greenland where water continues to flow from the Irminger Sea to the Labrador Sea. Based on simulated field data in SPNA obtained from Modular Ocean Model (MOM), the Lagrangian method is applied in the Ocean Model Connectivity Modeling System (CMS), to track particles in the Irminger Sea. The properties of particles, such as location and temperature along their trajectory, are calculated at advection timesteps. Origins of water reaching Cape Farewell through the Irminger Sea are discovered, including the source from the Denmark Strait, the Iceland-Scotland Ridge, and the South Iceland Basin. Water from these origins follows different routes before arriving at Cape Farewell and qualitative and quantitative analyses of these routes based on particle trajectories and particle numbers, provide insights into how water crosses the Irminger Sea and the importance of the routes. In summary, water following the route from the Denmark Strait contributes 25 percent of the water through the Irminger Sea arriving at Cape Farewell. Water follows a direct and straight route along the East Greenland Boundary, as the cold source in the surface layer (50-150m). Water staying in the Irminger Basin contributes 50 percent. It travels in curved and blended routes in a deep layer ...