Dissolved Organic Matter in the Global Ocean: A Primer

Area of Science:

• Marine chemistry
• Biogeochemical cycles
• Oceanography

Background:

• Marine dissolved organic matter (DOM) represents a significant carbon pool (~660 billion metric tons).
• Oceanic DOM dynamics are crucial for global carbon cycling and atmospheric exchange.
• Understanding molecular-level controls on DOM is essential but currently limited.

Purpose of the Study:

• To provide a global context for marine dissolved organic matter (DOM).
• To highlight the poorly understood role of microgels in marine DOM dynamics.
• To establish a foundation for future research into molecular-level DOM controls.

Main Methods:

• Literature review and synthesis of existing global ocean data.
• Analysis of the significance of DOM as a carbon reservoir.
• Identification of knowledge gaps in DOM molecular dynamics.

Main Results:

• Marine DOM is a vast carbon reservoir with annual to millennial exchange potential.
• Global ocean-scale dynamics of DOM are increasingly understood.
• The molecular-level control on DOM, particularly the role of microgels, remains poorly understood.

Conclusions:

• This manuscript establishes the global significance of marine DOM.
• It identifies critical knowledge gaps regarding microgels and molecular dynamics.
• It serves as a foundational context for future research into marine DOM cycling.