When hearing about climate change, do you often think of polar bears or penguins next to icebergs? In fact, the first things in the food chain that climate change affects are phytoplankton and micro-algae – organisms that are considered the actual lungs of the Earth.

In this article, CHANGE will reveal the critical role of phytoplankton and the heavy consequences that ecosystems, including humans, will have to face because of climate change.

Phytoplankton: Phytoplankton (from Greek phyto = plant; plankton = tiny sea creatures) is considered to be the basis for all life in the sea. According to NASA data, phytoplankton is responsible for producing at least 50% of the oxygen we breathe and ensuring that life in the oceans is possible.

Although phytoplankton is not defined as a “plant”, it is still able to perform photosynthesis. This remarkable process harnesses the sun’s energy to use carbon dioxide (CO2) and water to form sugars – the basis for most food chains on Earth.

The main product of photosynthesis is sugar, used in the construction of the cell, but it also has a crucial byproduct – atmospheric oxygen (O2). It is often thought that the trees of the Amazon are the lungs of our planet, but the fact is that half of the oxygen in the atmosphere comes from the sea, for which phytoplankton are primarily responsible. Thus, phytoplankton allows the existence of life in the oceans as well as outside of them; as the main food producers in the oceans, they are the basis for the marine food chain, and as oxygen producers, they are contributing to life at sea and on land.

However, burning fossil fuels and human activities emit a considerable number of greenhouse gases. Luckily, we have the oceans absorb a part of these emissions and decrease the planet’s temperature. However, this causes acidification in the marine environment, and it corrodes everything from shellfish and coral reefs to phytoplankton – organisms that have strong bonds with the ecosystem.

A good example is a krill that feeds on the tiny phytoplankton. Fish eat krill, and they become a food source for mammals, and so on. The food chain continues to the top rank of the chain – humans. Therefore, if one link in the food chain is affected, scientists will compare this issue in the ocean to human getting osteoporosis, because this acidification has an adverse effect on the entire food chain.

Climate change causes a rise in ocean temperature by about 0.2C per decade, on average, which is a crucial change. The warmer water is lighter and tends to stay on top of what is then a layer of colder water (ocean stratification). This affects phytoplankton growth and draws down the surface of CO2.

Once we see the close interconnection between humans and other species in the food chain, we will understand how much all organisms, including humans, will be impacted when climate change wipes out some microalgae from the ecosystem.

It is true that no one wants to experience the scenario that we will run out of fish and seafood sources in the ocean. CHANGE also believes that no one wants the only sound of the sea to be silent when all species’ lives are taken away by climate change.

Stay tuned for the following articles on the fanpage to see what we can do against the impacts of climate change.

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