Deviation of the Lagrangian particle tracing method in the evaluation of the Southern Hemisphere annual subduction rate

• Published in: Journal of Oceanology and Limnology
• Main Authors: Liu, Kai, Gao, Shan, Wang, Fan
• Format: Report
• Language: English
• Published: SCIENCE PRESS 2022
• Subjects: subduction rate; Lagrangian particle tracing method; mixed layer; tropical water; eastern subtropical mode water; Marine & Freshwater Biology; Oceanography; Limnology; MIXED-LAYER; EQUATORIAL PACIFIC; NORTH-ATLANTIC; MODE WATER; OCEAN; VARIABILITY; VENTILATION; SEA; Pacific; North Atlantic
• Online Access: http://ir.qdio.ac.cn/handle/337002/178112; https://doi.org/10.1007/s00343-021-1097-7

The classical Lagrangian particle tracing method is widely used in the evaluation of the ocean annual subduction rate. However, our analysis indicates that in addition to neglecting the effect of mixing, there are two possible deviations in the method: one is an overestimation due to not considering that the amount of subducted water at the source location may be inadequate during the late winter of the first year when the mixed layer becomes shallow, the other one is an underestimation due to the neglect of the effective subduction caused by strong vertical pumping. Quantitative analysis shows that these two deviations mainly exist in the low-latitude subduction areas of the South Pacific and South Atlantic. The two deviations have very similar distribution areas and can partially offset each other. However, the overall deviation is still large, and the maximum relative deviation ratio can reach 50%; therefore, it cannot be ignored.