Department of Geosciences, Auburn University, USA.
Department of Geosciences, Auburn University, USA.
Chemosphere. 2023 Jul;328:138547. doi: 10.1016/j.chemosphere.2023.138547. Epub 2023 Mar 28.
Spheroidal carbonaceous particles (SCPs) are atmospherically mobile by-products of anthropogenic, high-temperature fossil fuel combustion. Since they are preserved in many geologic archives across the globe, SCPs have been identified as a potential marker for the onset of the Anthropocene. Our ability to reliably model the atmospheric dispersal of SCPs remains limited to coarse spatial scales (i.e., 10-10 km). We address this gap by developing the DiSCPersal model, a multi-iterative and kinematics-based model for dispersal of SCPs at local spatial scales (i.e., 10°-10 km). Although simple and limited by available measurements of SCPs, the model is nonetheless corroborated by empirical data of the spatial distribution of SCPs from Osaka, Japan. We find that particle diameter and injection height are the primary controls of dispersal distance, whereas particle density is of secondary importance. Further, stark differences in the modelled dispersal distances of SCPs between non-point vs. smokestack sources could explain the ambiguity of dispersal distances and the relative magnitude of long-range vs. localized sourcing of SCPs reported in the literature. This research underscores the need to incorporate understanding of the localized dispersal patterns of SCPs when interpreting their preservation in geologic archives. By extension, our findings have implications for the reliability of SCPs as a globally synchronous marker for the onset of the Anthropocene.
球碳颗粒（SCPs）是人为的高温化石燃料燃烧产生的大气可移动副产物。由于它们在全球许多地质档案中都有被发现，因此 SCPs 已被确定为人类世开始的潜在标志。我们能够可靠地模拟 SCPs 的大气扩散的能力仍然仅限于粗空间尺度（即 10-10km）。我们通过开发 DiSCPersal 模型来解决这一差距，该模型是一种基于多迭代和运动学的 SCPs 局部空间尺度（即 10°-10km）扩散模型。尽管模型简单且受到 SCPs 可用测量的限制，但它仍然得到了来自日本大阪的 SCPs 空间分布的实证数据的支持。我们发现，颗粒直径和注入高度是扩散距离的主要控制因素，而颗粒密度则次之。此外，无组织源与烟囱源之间 SCPs 模拟扩散距离的显著差异可以解释文献中报道的 SCPs 长距离与本地化来源的扩散距离的模糊性和相对大小。这项研究强调了在解释地质档案中 SCPs 的保存时，需要纳入对 SCPs 局部扩散模式的理解。通过扩展，我们的研究结果对 SCPs 作为人类世开始的全球同步标志的可靠性具有影响。
