In 2015, 196 countries signed the Paris Agreement, which aims to reduce CO2 emissions. This obliges the states to take their own steps and enact regulations, such as the introduction of a carbon tax levy or the abolition of coal mines. Despite these measures, the targets put forward in the agreement have so far not been met. According to the Climate Change Report 2021 of the UN Intergovernmental Panel on Climate Change (IPCC), global surface temperatures will, given current emissions, continue to rise until mid-century. Global warming will thus surpass 1.5°C and 2°C respectively during the 21st century if CO2 and other greenhouse gas emissions are not sharply reduced in the coming decades.
 
The consequences of global warming are becoming increasingly clear: floods, droughts, hurricanes, glacier shrinkage or the rapid melting of the ice dominate the way we see the world. Images of polar bears on floating ice floes, detached from the permanent pack ice, are disturbing and thought-provoking. Such images make global warming more visible and give us an idea of its profound consequences.

The book featured in the current newsletter, "Slime - How Algae Created Us, Plague Us, and Just Might Save Us," addresses not only the history and unique properties of algae, but also their potential benefits in the fight against climate change. Ruth Kassinger describes how vital algae are, as well as how, if used and cultivated wisely, they could help us out of the climate crisis. Ruth Kassinger describes how vital algae are, as well as how, if used and cultivated wisely, they could help us humans out of the climate crisis. Even a single sip of salt water contains several thousand different algae, which are the most vital source of food for microscopic animals and thus make up the foundation of the marine food chain.

A die-off of all algae would therefore result in the starvation of all marine animals. Without algae, life on land would not have been able to evolve 500 million years ago. Algae are not only a source of food for many living organisms; they also ensure that the earth does not heat up too much and that it remains habitable. This is because dead algae and their carbon-rich husks remain in sea-floor sediments for a long time, thereby storing carbon dioxide from the atmosphere long term. In doing so, algae our planet from becoming an unbearable greenhouse.

The book introduces various projects aimed at cultivating algae, for example, to produce biofuel or compostable packaging. One example is the American shoe company Vivobarefoot, which replaces its foam components with algae and even makes some shoes entirely from algae, like its "Ultra III Bloom" model.  Other products made from algae include standup paddle boards and surfboards.

Algae extracts have also been in our food and cosmetic products for several years, serving as texturizers or gelling agents in shampoos, toothpaste, and yogurts.

Agar agar, a type of algae, even serves as a substitute for animal gelatin and has been used in medical laboratories as a growth medium for bacterial cultures for more than 150 years.

The freshwater algae chlorella or nori algae also contain vitamin B12, which is otherwise only found in animal products. However, B12 quantities can vary, depending on whether it is found in cultured or wild growing algae. Even if the latter contains larger B12 quantities, its is also often contaminated with pollutants that can be traced back to industrial wastewater, agricultural fertilizers, or waste degradation products. Unfortunately, these pollutants also promote uncontrolled and damaging algae growth. In this context, one also speaks of algae bloom or algae plague, since the algae produce toxic substances that can lead to life-threatening poisoning in humans and animals.

Algae farms supply the food or pharmaceutical industries and can be found all over the world. One of the largest algae farms (Algomed) in Europe is in Germany. Here, chlorella algae grow in a closed 500-kilometer-long tube system that is protected from pollutants. Another project in the field of algae exploitation is the so-called iron fertilization, which aims to reduce carbon dioxide by selectively fertilizing iron-deficient areas in the ocean with iron, which in turn promotes algae growth.

If we were to rely more on algae as part of our diet and that of livestock, this would undoubtedly have a positive impact on the climate. The article "Algae - raw material of the future?" published in the current Mondberge magazine also confirms this, according to which 50 times less land and 300 times less water is needed for one kilogram of Spirulina-based protein than for one kilogram of beef protein.

For us to continue to benefit from algae's properties, it is essential that we drastically reduce CO2 emissions. Currently, one of the largest sources of emissions is still rainforest clearing. Efforts to save the planet's lungs are therefore imperative. By buying food and cosmetic products without palm oil, avoiding air travel as far as possible, using electricity from renewable energy sources, and greatly reducing meat consumption, we can all contribute to reducing CO2 emissions.

Ruth Kassinger is the author of several scientific and historical books. She lives in the USA and holds degrees from Yale and Johns Hopkins University.

Her book "Slime - How Algae Created Us, Plague Us, and Just Might Save Us" is available in stores and can also be read upon advance notice at the TIR library, where reading and workstations are available. Recent additions to the TIR Library will each be featured in our library newsletter.