18 December 2025 / Kiel / Plymouth. The ocean may have absorbed significantly more carbon dioxide (CO₂) than previously calculated. A new study by the GEOMAR Helmholtz Centre for Ocean Research Kiel and the Plymouth Marine Laboratory shows that the exchange of gases between air and sea is not symmetric, and that the global ocean has taken up around 15 per cent more CO₂ than suggested by conventional estimates. In windy regions, air bubbles entrained by breaking waves substantially enhance the uptake of CO₂. The results are based on extensive direct measurements from the ocean and have now been published in the journal Nature Communications.

Solar-driven interfacial desalination (SID) offers a sustainable route for freshwater production, yet its long-term performance is compromised by salt crystallization and microbial fouling under complex marine conditions. Zwitterionic polymers offer promising nonfouling capabilities, but current zwitterionic hydrogel-based solar evaporators (HSEs) suffer from inadequate hydration and salt vulnerability. Inspired by the natural marine environmental adaptive characteristics of saltwater fish, we report a superhydrated zwitterionic poly(trimethylamine N-oxide, PTMAO)/polyacrylamide (PAAm)/polypyrrole (PPy) hydrogel (PTAP) with dedicated water channels for efficient, durable, and nonfouling SID. The directly linked N⁺ and O⁻ groups in PTMAO establish a robust hydration shell that facilitates rapid water transport while resisting salt and microbial adhesion. Integrated PAAm and PPy networks enhance mechanical strength and photothermal conversion. PTAP achieves a high evaporation rate of 2.35 kg m⁻² h⁻¹ under 1 kW m^–2 in 10 wt% NaCl solution, maintaining stable operation over 100 h without salt accumulation. Furthermore, PTAP effectively resists various foulants including proteins, bacterial, and algal adhesion. Molecular dynamics simulations reveal that the exceptional hydration capacity supports its nonfouling properties. This work advances the development of nonfouling HSEs for sustainable solar desalination in real-world marine environments.