Freeman Danielle Haas, Ward Collin P
Department of Marine Chemistry and Geochemistry, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA.
Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
Sci Adv. 2022 Feb 18;8(7):eabl7605. doi: 10.1126/sciadv.abl7605. Epub 2022 Feb 16.
Oxygenation reactions initiated by sunlight can transform insoluble components of crude oil at sea into water-soluble products, a process called photo-dissolution. First reported a half century ago, photo-dissolution has never been included in spill models because key parameters required for rate modeling were unknown, including the wavelength and photon dose dependence. Here, we experimentally quantified photo-dissolution as a function of wavelength and photon dose, making possible a sensitivity analysis of environmental variables in hypothetical spill scenarios and a mass balance assessment for the 2010 (DwH) spill. The sensitivity analysis revealed that rates were most sensitive to oil slick thickness, season/latitude, and wavelength and less sensitive to photon dose. We estimate that 3 to 17% (best estimate 8%) of DwH surface oil was subject to photo-dissolution, comparable in magnitude to other widely recognized fate processes. Our findings invite a critical reevaluation of surface oil budgets for both DwH and future spills at sea.
由阳光引发的氧化反应可将海洋中原油的不溶性成分转化为水溶性产物，这一过程称为光溶解。光溶解在半个世纪前首次被报道，但由于速率建模所需的关键参数未知，包括波长和光子剂量依赖性，它从未被纳入溢油模型。在这里，我们通过实验量化了光溶解与波长和光子剂量的函数关系，从而能够对假设溢油情景中的环境变量进行敏感性分析，并对2010年深水地平线（DwH）溢油事故进行质量平衡评估。敏感性分析表明，光溶解速率对浮油厚度、季节/纬度和波长最为敏感，而对光子剂量不太敏感。我们估计，DwH海面油污的3%至17%（最佳估计为8%）发生了光溶解，其规模与其他广泛认可的归宿过程相当。我们的研究结果促使人们对DwH以及未来海上溢油事故的海面油污预算进行批判性重新评估。
