Abstract：
Since the transfer of microplastic across the sea-air interface was first reported in 2020, numerous studies have been conducted on its emission flux estimation. However, these studies have shown significant discrepancies in the estimated contribution of oceanic sources to global atmospheric microplastics, with evaluations ranging from predominant to negligible, varying by 4 orders of magnitude from 7.7 × 10-4 to 8.6 megatons per year, thereby creating considerable confusion in the research on the microplastic cycle. Here, we provide a perspective by applying the well-established theory of particulate transfer through the sea-air interface. The upper limit of global sea-air emission flux microplastics was calculated, aiming to constrain the controversy in the previously reported fluxes. Specifically, the flux of sub-100 μm microplastic cannot exceed 0.01 megatons per year, and for sub-0.1 μm nanoplastics, it would not exceed 3 × 10-7 megatons per year. Bridging this knowledge gap is crucial for a comprehensive understanding of the sea-air limb in the \"plastic cycle\", and facilitates the management of future microplastic pollution.
摘要：
自从2020年首次报道微塑料在海-气界面上的转移以来，已经对其排放通量估算进行了大量研究。然而,这些研究表明，海洋资源对全球大气微塑料的估计贡献存在重大差异，评价从主要到微不足道，从每年7.7×10-4到8.6兆吨，相差4个数量级，从而在微塑料循环的研究中造成了相当大的混乱。这里,我们通过应用完善的颗粒通过海-气界面转移的理论提供了一个观点。计算了全球海洋空气排放通量微塑料的上限，旨在限制先前报道的通量中的争议。具体来说,亚100μm微塑料的通量每年不能超过0.01兆吨，对于低于0.1μm的纳米塑料，每年不会超过3×10-7兆吨。弥合这一知识差距对于全面了解“塑性循环”中的海空肢体至关重要，并促进未来微塑料污染的管理。
