The **ocean** harbors organisms invisible to the naked eye that are vital for life on the planet. Among them, the Prochlorococcus, a type of microscopic **[phytoplankton](https://noticiasambientales.com/medio-ambiente/el-deshielo-en-groenlandia-impulsa-la-vida-marina-cientificos-detectan-un-aumento-de-hasta-el-40-en-fitoplancton/)**, stands as the most abundant on Earth and is responsible for generating more oxygen than all the **forests and jungles** combined. Despite measuring less than one-thousandth of a millimeter, it produces around 55% of the dissolved atmospheric oxygen.
Its role is not limited to oxygen production. This phytoplankton constitutes the **base of the marine food chain**, feeding zooplankton, which in turn sustains small, medium, and large fish, eventually reaching humans as the last link. Without this organism, both the **marine and terrestrial balance** would be severely affected as a consequence of climate change.
Recent research warns that the increase in **ocean temperatures** seriously threatens its **survival**. Predictive models indicate that, under scenarios of extreme warming, the abundance of *Prochlorococcus* could decrease by 17% to 51% by the end of this century, especially in **tropical waters**.
A group of American scientists conducted a study over a decade, covering over 278,000 kilometers of ocean and analyzing millions of water samples in real-time. Through flow cytometry techniques, they observed that the **reproduction rate** of this phytoplankton increases with heat but **collapses** when the temperature exceeds **28 to 30 degrees**, as stated in the article published in the journal **[Nature Microbiology](https://www.nature.com/articles/s41564-025-02106-4)**.
## Phytoplankton as an Ocean Thermometer
The Prochlorococcus thus becomes an **indicator organism of environmental disturbances** linked to climate change. Its collapse reflects the fragility of marine food webs in the face of rising temperatures, water acidification, and **biodiversity loss**.
Warmer oceans affect not only this tiny oxygen producer but also the entire chain that depends on it. From zooplankton species to large marine vertebrates, their survival can be compromised, altering the dynamics of marine life **distribution** in extensive regions.
In fact, the disappearance or decline of these populations could lead to a domino effect on coastal and oceanic ecosystems. Scientific evidence suggests that the **loss of key organisms** like **phytoplankton** could trigger global ecological crises, even with repercussions on human food security.
## Tiny yet Essential for the Planet’s Life
Phytoplankton, like terrestrial plants, **photosynthesize** and convert solar energy into oxygen and nutrients. However, their contribution goes beyond: being present in all oceans, they sustain water productivity and serve as initial food for marine life.
This process makes Prochlorococcus and other types of **[phytoplankton](https://noticiasambientales.com/medio-ambiente/cambios-en-el-color-de-los-oceanos-revelan-una-redistribucion-global-del-fitoplancton-como-afecta-esto-al-planeta/)** true **lungs of the planet**, responsible for regulating the climate and maintaining atmospheric stability. Additionally, they play a key role in the carbon cycle by absorbing **carbon dioxide** from the atmosphere and fixing it in the oceans.
The importance of their role transcends the **ecological** realm: the health of marine life, and ultimately that of humans, depends on their balance. Therefore, the threat facing this organism due to **global warming** is an urgent call to strengthen **environmental policies** and reduce **greenhouse gas emissions**.
Source: UNQ Scientific News Agency.
