The Blue Cooling Initiative (BCI) is at the forefront of efforts to combat global warming through a combination of temporary and long-lasting solutions. By accelerating the development and deployment of Marine Cloud Brightening and other climate cooling strategies, and by addressing the root causes of climate change, BCI aims to pave the way for a sustainable and cooler planet. Immediate and collaborative action is essential to prevent crossing critical climate thresholds and to protect our planet’s biodiverse ecosystem for future generations.

Ocean-based climate cooling solutions

Marine Cloud Brightening (MCB) aims to reflect more sunlight back into space by enhancing the reflectivity of clouds over the ocean. The process involves:

  • Spraying Seawater: Devices over the ocean surface spray fine mist of seawater.
  • Aerosol Formation: These droplets evaporate, leaving salt aerosols that rise into the atmosphere.
  • Cloud Interaction: The salt aerosols act as condensation nuclei, making clouds whiter and more reflective.
  • Increased Albedo: Brighter clouds reflect more sunlight, reducing the amount of solar energy absorbed by the Earth.

Benefits of MCB

  • Rapid Cooling: MCB can quickly reduce temperatures, providing immediate relief from extreme heat and buying time for longer-term solutions.
  • Scalability: This technology can be deployed on a regional basis, targeting specific areas most affected by climate change.
  • Natural Process Mimicry: By enhancing natural sea spray processes, MCB represents a biomimetic approach, minimizing potential ecological disruptions.

Buoyant Flakes Ocean Fertilization

A promising technology in restoring nutritional balance in oceanwater and eventually brightening clouds as a by-product via DMS (dimethyl sulphide). This concept is currently being tested in the Indian Ocean, in a cooperation with the Centre for Climate Repair at Cambridge University. This might be interesting after implementation over very large areas as a natural takeover of MCB. This biomimetic strategy has mostly indirect cooling effetc and contributes to tackling root the cause.

More about buoyant flakes ocean fertilization (external link)

Fizz Tops (Fiztops) 

Fiztops are table sized, floating, lightweight, solar-powered units that are designed to inject nanobubbles into the sea surface microlayer (SSML). They may either be anchored to cool a specific area of ocean, coral reef or aquaculture operation, or else be free-floating. Works with the same ideas as Bright Water technology. Is still in its very conceptual phase. (Harvard University)

SML layer explainer video, courtesy of the Schmidt Ocean Institute

Studying the SML layer, courtesy of the Schmidt Ocean Institute

More about Fiztops (external link)

Ocean Thermal Energy Conversion (OTEC) 

Ocean Thermal Energy Conversion would utilize the temperature difference between surface and deeper ocean waters to cool the planet while generating baseload energy and removing CO2 from the atmosphere. OTEC is operational from a temperature difference of 20 °C. Typical locations are therefore coastal regions of tropical areas. OTEC is different to MCB but quite promising because of the indirect cooling. Could potentially take over the cooling process of MCB in the long run.

TU Delft – OTEC explainer video

More about TU Delft OTEC (external link)

Arctic Ice Management

Artificially thicken the polar ice pack is the ambition of the TU Delft start-up Arctic Reflections. Thicker polar ice could be created by pumping polar sea water to the Arctic Sea ice surface in the winter. Heat released by freezing would be emitted to space during winter, while in the warmer months the increased surface would reflect more Solar Radiation. Arctic Reflections is planning to conduct a test on Spitsbergen.

Artic Reflections explainer video, courtesy: Innovation Quarter

More about TU Delft’s Artic Reflections (external links)

WaterWattS – Ocean Heat Conversion 

WaterWattS offers an innovative way to use the self-ionization in water to enable the conversion of aqueous heat to chemically stored energy. Water constantly splits into its ionic components OH- and H3O+, creating process kinetics and an 80 Watt/liter endothermic reaction. WaterWattS  produces H₂-energy plus cooling.  

More about WaterWattS (external links)

Iron Salt Aerosol (ISA) 

Iron salt aerosol was a main factor in planetary cooling in the ice ages. It mimics natural dust deposition by very diffusely fertilizing large ocean areas, drawing down CO2 and increasing ocean biomass. This increases the ‘smell of the sea’ (dimethyl sulfide or DMS), an aerosol from marine algae that makes clouds, which cool the ocean beneath them. ISA could be dispersed from offshore wind turbines and be combined with MCB.

More about Iron Salt Aerosol (ISA) (external link)