Marine dimethylsulfide (DMS) is an important source of natural sulfur to the atmosphere, with potential implications for the Earth’s radiative balance. Coral reefs are important regional sources of DMS, yet their contribution is not accounted for in global DMS climatologies or in model simulations. This study accounts for coral-reef-derived DMS and investigates its influence on the atmosphere of the Great Barrier Reef (GBR), Australia, using the Australian Community Climate and Earth System Simulator Atmospheric Model version 2 (ACCESS-AM2). A climatology of seawater surface DMS (DMS_w) concentration in the GBR and an estimate of direct coral-to-air DMS flux during coral exposure to air at low tide are incorporated into the model, increasing DMS emissions from the GBR region by 0.02 Tg yr^-1. Inclusion of coral-reef-derived DMS increased annual mean atmospheric DMS concentration over north-eastern Australia by 29%, contributing to an increase in gas-phase sulfate aerosol precursors of up to 18% over the GBR. The findings suggest that the GBR is an important regional source of atmospheric sulfur, with the potential to influence local-scale aerosol-cloud processes. However, no influence on sulfate aerosol mass or number concentration was detected, even with a reduction in anthropogenic sulfur dioxide emissions, indicating that DMS may not significantly influence the regional atmosphere at monthly, annual or large spatial scales. Further research is needed to improve the representation of coral-reef-derived DMS in climate models and determine its influence on local, sub-daily aerosol-cloud processes, for which observational studies suggest that DMS may play a more important role.

海洋二甲基硫醚 (DMS) 是大气中天然硫的重要来源，对地球辐射平衡具有潜在影响。珊瑚礁是 DMS 的重要区域来源，但在全球 DMS 气候学或模型模拟中并未考虑它们的贡献。本研究考虑了珊瑚礁衍生的 DMS，并使用澳大利亚社区气候和地球系统模拟器大气模型 2 (ACCESS-AM2) 调查其对澳大利亚大堡礁 (GBR) 大气的影响。GBR中海水表面 DMS (DMS _w ) 浓度的气候学和珊瑚在低潮时暴露于空气期间直接珊瑚到空气 DMS 通量的估计被纳入模型，使 GBR 地区的 DMS 排放增加 0.02 Tg年^-1. 包含珊瑚礁衍生的 DMS 使澳大利亚东北部的年平均大气 DMS 浓度增加了 29%，导致 GBR 上的气相硫酸盐气溶胶前体增加了 18%。研究结果表明，GBR 是大气硫的重要区域来源，有可能影响局部尺度的气溶胶云过程。然而，即使人为二氧化硫排放量减少，也没有检测到对硫酸盐气溶胶质量或数量浓度的影响，这表明 DMS 可能不会在月、年或大空间尺度上显着影响区域大气。需要进一步研究以改善珊瑚礁衍生的 DMS 在气候模型中的代表性，并确定其对当地次日气溶胶云过程的影响，