Rainfall has a significant impact on carbon sequestration in the ocean, according to a recent study led by oceanographer David Ho. Ho’s research shows that rain enhances the transfer velocity of carbon dioxide (CO2) from the air to the water, ultimately increasing the ocean’s uptake of CO2 by 5% to 7% annually.
Ho’s study is the first to provide a comprehensive global estimate of the effects of rainfall on CO2 fluxes in the ocean. The research demonstrates that raindrops not only bring fresh water to the surface but also increase turbulence, dilution, and wet deposition, all of which contribute to higher carbon uptake in the ocean.
One surprising finding of the study is that the impact of rain on carbon sequestration is not limited to tropical regions with heavy rainfall. The researchers found that rain-induced effects are also significant in higher latitudes, where precipitation patterns are changing due to climate change.
The study’s model, developed by coauthor Hugo Bellenger, tracks rain-induced salinity changes at the ocean surface and highlights the regions where rain has the strongest impact on carbon uptake. The researchers hope that by quantifying these small-scale processes at the air-sea interface, scientists will be able to improve their models of carbon flows between the atmosphere and the ocean.
As the world warms and precipitation patterns shift, the impact of rain on carbon sequestration in the ocean is expected to grow stronger. The researchers observed a slight growing trend in the effect of rain on the ocean’s carbon uptake from 2008 to 2018, based on satellite observations and global weather datasets.
This research underscores the importance of considering the effects of precipitation on the global carbon budget. By understanding how rain influences carbon sequestration in the ocean, scientists can better predict the ocean’s role in mitigating climate change. The study’s findings have direct implications for quantifying the ocean carbon sink and highlight yet another carbon-climate feedback that must be taken into account in global models.
Veronika Meduna, a science editor and journalist, emphasizes the significance of this research in addressing climate change and understanding the complex interactions between the atmosphere and the ocean. By shedding light on the role of rainfall in carbon sequestration, this study contributes valuable insights to the ongoing efforts to combat global warming and its impacts on the environment.
