Feedback Mechanisms Between Atmospheric and Oceanic Factors on Atmospheric CO2 Concentration Over Tropical Coastal Waters

• Published in: Earth systems and environment 2024-12, Vol.8 (4), p.1893-1916
• Main Authors: Sigid, Muhammad Fikri, Yusup, Yusri, Swesi, Abdulghani Essayah, Almdhun, Haitem M., Jamshidi, Ehsan Jolous
• Format: Article
• Language: English
• Subjects: Air temperature; Atmosphere; Carbon cycle; Carbon dioxide; Carbon dioxide concentration; Carbon dioxide emissions; Carbon sequestration; Carbon sinks; Carbon sources; Climate; Climate Change/Climate Change Impacts; Climate system; Coastal processes; Coastal waters; Coastal zone; Dilution; Earth and Environmental Science; Earth Sciences; Earth System Sciences; Environmental Science and Engineering; Fluctuations; Geography; Monitoring/Environmental Analysis; Monsoons; Ocean models; Oceans; Original Article; Radiation; Rain; Rainfall; Research methodology; Salinity; Salinity effects; Seasonal variations; Solubility; Temperature; Water temperature; Wind; Wind effects; Wind speed
• ISSN: 2509-9426; 2509-9434
• DOI: 10.1007/s41748-024-00448-3

The carbon cycle process in coastal areas is essential in the Earth’s climate system. Atmospheric CO 2 concentration over the coastal waters can be influenced by CO 2 flux and various atmosphere–ocean parameters. Understanding these relationships is essential for modeling and assessing carbon storage control. This research investigates the differences in air-sea exchanges during the northeast and southwest monsoons and their impact on atmospheric CO 2 concentration over tropical coastal waters from 2016 until 2019. Throughout the study period, the coastal waters functioned as a carbon sink (–0.023 µmol m –2  s –1 ), with CO 2 flux more strongly influenced by sea surface salinity than water temperature and CO 2 solubility in water. The overall carbon uptake suggests a potential reduction in atmospheric CO 2 concentration, as CO 2 flux notably contributes to its levels. However, seasonal variability distinctly impacts CO 2 flux. During the southwest monsoon, the coastal waters act as a carbon source (0.006 µmol m –2  s –1 ), primarily influenced by lower water temperature and higher CO 2 solubility, contributing to a higher CO 2 emission. Conversely, during the northeast monsoon, the coastal waters act as a carbon sink (–0.051 µmol m –2  s –1 ), with a reduced CO 2 absorption, strongly affected by increased rainfall and lower sea surface salinity. Horizontal transport-induced changes in atmospheric CO 2 concentration can influence CO 2 flux through dilution effects, contributing to higher carbon sources during the southwest monsoon and lower carbon uptake during the northeast monsoon, particularly during the northeast monsoon characterized by the higher wind speed.