How CO2 travels through the ocean, packaging made from pollution and 6 online climate communities

Issue No5

Did you know that shrimps build their shells from CO2? Today we have a look at how carbon gets from the air to the ocean and how too much of it threatens marine life. All stories in this issue:

  • How CO2 travels through the ocean

  • Knowledge snack: A great whale is worth 1000 trees

  • How they do it: Plastic packaging made from pollution

  • Best pick: 6 online climate communities

  • Future fantasy: Babies for space (with illustration)

My favourite discovery of this edition are tiny little organisms called coccoliths and  foraminiferans – they look super cool and capture atmospheric carbon.

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Thank you for your support in 2020. I wish you limitless energy in the new year!

Ocean sinks: Pumps and projects that transport carbon through the seas

The oceans are considered natural carbon ‘sinks’ since they take up more CO2 than they release. The main story in bullet points:

  • The ocean absorbs a quarter of man-made greenhouse gases.

  • CO2 enters the ocean on the surface and then follows three major paths:

    • Carbon enters the marine food chain through phytoplankton.

    • Coral, oysters, shrimps and shells are built from carbon.

    • Cold water transports dissolved CO2 down to the deep ocean.

  • The ocean balances out the carbon in the atmosphere: the more there is, the more the ocean absorbs.

  • The more CO2 seawater absorbs, the warmer and more acid it gets. These effects threaten many marine organisms.

  • The enhancement of coastal ecosystems, addition of nutrients to the sea surface to stimulate phytoplankton photosynthesis or spreading of rock particles intent to ‘heal’ oceans and accelerate carbon uptake.

Carbon travels between the atmosphere and the earth. Venting volcanoes and decomposing plants boost billions of tonnes of carbon dioxide into the atmosphere. In return the biosphere absorbs large amounts of carbon. We already looked into how plants store carbon in the soil. Now we want to know more about how the seas are soaking up CO2. 

CO2 enters the ocean on the surface when it winds or rains. The carbon dioxide then follows down three distinct paths

  1. The biological carbon pump: When the sun hits the sea, tiny marine organisms called phytoplankton capture atmospheric carbon. Just like plants, phytoplankton sequester carbon through photosynthesis. Phytoplankton are the beginning of the marine food chain: they are eaten by small fish, who are consumed by larger fish. These fish poop and die(if they are not eaten). Dung and carcasses sink and settle in the sediments on the seabed. The process is also called marine snow (I hope you continue enjoying snow falling from the sky).

  2. The carbonate pump: some chemical process that I honestly don’t understand enough, but this site explains it quite well. Basically, the ocean carbonate system helps to form coral, oysters, shrimps and shells.

  3. The physical carbon pump, also called solubility pump: carbon dioxide is soluble and can dissolve into water. Water doesn't just stream around the globe, it also travels up and down. Cold water sinks and transports dissolved CO2 down to the deep ocean. It can stay there for hundreds of years before it returns to the surface and releases some of the dissolved CO2 back to the atmosphere.

The pumps can also interact with each other, since seawater is like a soup in a big bowl. In total the ocean bowl absorbs about a quarter of all CO2 we release into the atmosphere. In fact, the ocean balances out the carbon in the atmosphere: as emission levels increase, the amount of carbon dioxide absorbed by the ocean also increases. This makes oceans more acid, which reduces the amount of carbonate and makes it harder for marine organisms like shrimps to grow their shell. Vicious cycle.

Knowledge snack: A great whale is worth 1000 trees

A great whale can absorb 33 tons of CO2 throughout his lifetime: “Whales accumulate carbon in their bodies during their long lives. When they die, they sink to the bottom of the ocean; each great whale sequesters 33 tons of CO2 on average, taking that carbon out of the atmosphere for centuries. A tree, meanwhile, absorbs only up to 48 pounds of CO2 a year.” The National Geographic estimates protecting whale populations could be equalising the annual carbon emissions of Brazil. If the 1.3 million great whales could be increased to the pre-commercial population level of 4-5 million, they could capture about 1.7 billion tons of carbon dioxide each year.

The question is, can we manipulate the ocean carbon cycle to take more or release less CO2? The short answer is yes. Climate engineering approaches to ‘heal’ oceans and accelerate carbon uptake include:

  • Ocean fertilization: adding nutrients to the surface ocean to stimulate photosynthesis.

  • Blue carbon: growing mangroves, salt marshes, seagrasses and macroalgae.

  • Oceanic enhanced weathering: spreading rock particles, also reduces ocean alkalinity.

Much of the risks and side effects remain to be examined. Here are a variety of projects that are working on better understanding and utilising the oceans to accelerate the removal of carbon from the atmosphere: 

  • GreenWave is growing a mix of seaweeds and shellfish while sequestering carbon and rebuilding reef ecosystems, bringing a centuries old industry back.

  • Project Vesta is creating green sand beaches from olivine rocks. Spreading the sand on 2 % of the coastline could remove 100% of man-made GHG.

  • Econcrete produces concrete units that enhance biological life of oceans and coasts.

  • Urchinomics is harvesting sea urchins to make space for kelp to grow.

  • Ocean-based develops an oxygenator pump to facilitate downwelling of CO2 seawater. 

  • Saildrone is not directly removing CO2, but delivering important information via a fleet of self-surfing boats.

  • Coral Vita restores dying coral reefs. (Netflix’s Chasing Coral is a great documentary on the bleaching phenomena of corals).

  • Arc Marine is accelerating reef creation by building marine habitat structures.

There is much potential. The ocean covers 70% of earth's surface. Our natural and technological climate solutions are often by default focused on land. I have a feeling the ocean needs more attention and we should promote both efforts – protecting whales and trees – whilst we continue to understand the risks and implications of our interactions. There is no way back, voluntarily or involuntarily, we are engineering the climate.

The “How they do it” section explores how businesses are tackling climate change

How they do it: Plastic packaging made from pollution

In France three firms managed to turn carbon emissions into a packaging material. The  companies Lanzatech, Total and L'Oréal announced their breakthrough this October. This is how they do it: 

  1. LanzaTech recycles industrial carbon emissions into ethanol.

  2. Total converts the ethanol into ethylene before polymerizing it into polyethylene.

  3. L’Oréal uses this polyethylene to produce plastic cosmetic bottles.

L’Oréal Packaging & Development Director Jacques Playe said that “We have the ambition to use this sustainable material in our bottle of shampoo and conditioner by 2024 and we hope other companies will join us in using this breakthrough innovation.”

The “Best pick” section present a selected article, podcast, video or other resource

Best pick: 6 online climate communities

If you are into technology and climate change, here are half a dozen great communities to join on slack, discord and the like:


  2. Tomorrow

  3. Impact Makers

  4. Yale Openlab Collabathon

  5. My Climate Journey (paid)

  6. Witnesses Of Climatology

See you there!

The “Future fantasy” section provides a fictional short story

Future fantasy: Babies for populating space

28.03.2041 - Earlier this century the theory circulated that having children is the most harmful thing people do to the world. This notion no longer sounds odd. Today, the members of the United Nations have passed a global one-child policy. There are more plans. According to the Population Bureau, women can now even sell their surplus eggs. The eggs will be frozen and sent to the moon, where they are kept in the Space Colonization Center. The center is a launching hub to reach unpopulated planets. The eggs will be transported on spaceships alongside people and medical equipment to guarantee genetic variance and healthy population growth. No one knows yet if and how the concept of a family remains, will there even be brothers, sisters, mothers and fathers? Back on earth it seems the plans are well received by the UN officials, Miguel Fernandéz from Mexico said to the press “This is the best solution for both, the earth and space. We need babies to colonize the universe”.

In the next issue

Artificial intelligence and climate change, a Knowledge snack, How they do it, Best picks and another Future fantasy will wait for you. In the meantime you can also get updates on your preferred social channel: Linkedin, Instagram, Twitter, Facebook or Youtube. If you want to receive the next issue, subscribe now. Together we can help reverse climate change.