Details

Autor(en) / Beteiligte

• Guo, Junting
• Zhao, Zihan
• Cao, Ruichen
• Lv, Xianqing

Titel

Regional to global assessments of ocean transparency dynamics from 1997 to 2019

Ist Teil von

• Progress in oceanography, 2023-12, Vol.219, p.103165, Article 103165

Ort / Verlag

Elsevier Ltd

Erscheinungsjahr

2023

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• •Multiple timescale variations of Zsd on regional to global scales are revealed.•Zsd monthly climatology dynamics of 22 typical ocean areas are investigated.•The long-term trends of Zsd show the widespread expansion of oligotrophic waters.•The first comprehensive evaluation in global Zsd dynamics over the past two decades. Water transparency, often quantified using the Secchi disk depth (Zsd), is a key parameter for assessing the water quality and ecological health in marine environments. However, a limited understanding of global Zsd dynamics over the past two decades exists. To assess the variations of ocean transparency over multiple timescales, the Ocean Colour Climate Change Initiative (OC-CCI) datasets are used to retrieve monthly global Zsd products during 1997–2019. On regional to global scales, significant Zsd variations on seasonal, interannual, and long-term timescales are identified. Seasonal and interannual variations of Zsd in most open oceans are found to be closely linked to phytoplankton dynamics and climate change. In the coastal zones, the Zsd variability is attributed to various physical and environmental factors, including seasonal monsoons, river outflow, sediment resuspension, eutrophication, etc. Moreover, the climatological seasonal Zsd variations of 22 typical ocean areas and the associated influencing factors are investigated on regional scales. The long-term trends of Zsd suggest the widespread expansion of oligotrophic waters within the North Pacific, North Atlantic, and South Indian Ocean gyres, indicating ongoing ocean desertification. The OC-CCI Zsd datasets can be used to build a merged centennial time series of Zsd in marine optics by linking to historical measurements. By relying on satellite-derived products, global and time-varying images offer a more comprehensive understanding of regional to global Zsd dynamics.