Effect of trajectory on particles' cumulative solar radiation exposure simulated by the Connectivity Model System (CMS) model, 2018-01-15 to 2018-12-30

Sunlight irradiance is a source of energy for life on Earth but it can also be a stressor at high dose; marine systems are no exception. Irradiance varies spatially, temporally and with the water bio-optical characteristics and depth, and this variability is expected to increase with climate change. Therefore, quantifying the exposure of living organisms or of particles in the ocean is key to accurately address light-related processes affecting them. Yet, current irradiance exposure estimates are static and neglect the movements of ocean currents or of organisms controlling their vertical distribution. This dataset was generated with the first numerical model capable of tracking the cumulative irradiance of moving particles in a moving ocean. Our novel biophysical modeling framework explicitly estimates the exposure to solar energy irradiance by encompassing ocean circulation modeling output, individual particles’ behavior, and time-varying irradiance from a global environmental model. Several examples of particle trajectories and their exposure to UV radiation are provided for five regions of the global ocean. One set of simulations models virtual organisms, with and without diurnal vertical migration (DVM), which are released as a cohort and tracked for seven days. An additional simulation modeled the passive drift of particles, such as microplastics, drifting in the ocean. In this case, the particles were released in a transect across the Atlantic and tracked for a full year.

太阳光辐照度(Sunlight irradiance)是地球生命的能量来源之一，但当剂量过高时也会成为胁迫因子；海洋生态系统亦不例外。辐照度会随空间、时间以及水体生物光学特性和水深发生变化，且这种变化幅度预计将随气候变化进一步加剧。因此，量化海洋中生物体或颗粒物的辐照度暴露量，是精准解析影响其生命活动的光相关过程的核心前提。然而，当前的辐照度暴露量估算均为静态估算，未考虑洋流或调控自身垂直分布的生物体的运动影响。本数据集由首个可在动态海洋中追踪运动颗粒物累积辐照度的数值模型生成。本研究提出的新型生物物理建模框架(biophysical modeling framework)整合了海洋环流模拟结果、单个颗粒物的行为特征以及来自全球环境模型的时变辐照度数据，可精准估算生物体所受的太阳光辐照度暴露量。本数据集提供了全球海洋5个区域的颗粒物运动轨迹及其受紫外线辐射(UV radiation)暴露的若干示例。其中一组模拟以种群形式释放虚拟生物体，分别设置具备昼夜垂直迁移(diurnal vertical migration, DVM)和不具备该行为的场景，并对其进行为期7天的追踪。另一组模拟则针对海洋中被动漂移的颗粒物（如微塑料(microplastics)）进行建模。在此场景中，颗粒物被释放于横跨大西洋的样带中，并被追踪一整年。