The icy desert of Antarctica is rapidly warming due to human-induced climate change. Meanwhile, scientists have unexpectedly discovered that penguins are allies in the fight against global warming on the continent. A new study from researchers at the University of Helsinki reveals that ammonia released into the atmosphere through penguin droppings creates an additional cloud cover over the Antarctic coast. This cloud cover blocks sunlight and lowers temperatures, as reported by Science Alert.
According to lead author Matthew Boyer, laboratory studies had previously indicated that gaseous ammonia could contribute to cloud formation. However, he noted, “It has been challenging to quantitatively assess this process and observe its impact in Antarctica until now.” Scientists believe Antarctica serves as an ideal natural laboratory. With virtually no anthropogenic pollution and sparse vegetation—meaning few alternative sources of cloud-forming gases—penguin colonies dominate as sources of ammonia.
However, the future of these birds is at risk. The shrinking sea ice disrupts their nesting, feeding, and predator protection processes. Yet, as it turns out, the ecological role of penguins is incredibly significant. Like other seabirds, such as imperial cormorants, they release large amounts of ammonia through their waste. When this ammonia combines with sulfur-containing gases from phytoplankton, tiny aerosol particles form, which eventually develop into clouds.
How did researchers uncover this? Boyer’s team installed instruments at the Argentine Marambio base on Seymour Island, near the northern tip of the Antarctic Peninsula. Over three summer months, when the Adélie penguin colonies were bustling and phytoplankton photosynthesis peaked, scientists monitored wind direction, ammonia levels, and newly formed aerosols. When the wind blew from a colony of 60,000 Adélie penguins located eight kilometers from the base, ammonia levels in the atmosphere surged to 13.5 parts per billion—about a thousand times higher than background levels. Even a month after the birds embarked on their annual migration, the concentration of droppings remained a hundred times higher. The ground, saturated with droppings, resembled land treated with slow-release fertilizers.
The instruments confirmed that aerosol particles were released into the atmosphere every time air masses arrived from the colony, sometimes so dense that fog formed. Chemical traces in the particles indicated ammonia derived from penguins.
Boyer referred to the connection between penguins and phytoplankton as a “synergistic process.” This process facilitates the formation of protective clouds over Antarctica. “We have evidence that a decline in penguin populations could lead to warming in the summer atmosphere of Antarctica,” the researchers stated in their report. On a global scale, clouds have a net cooling effect: they reflect solar radiation back into space. However, this effect also depends on what lies beneath the clouds. Ice sheets and glaciers reflect most solar rays, so additional cloud cover over these bright surfaces could even trap infrared heat. This means that the overall effect depends on where clouds form and drift.
“This is yet another example of the deep connection between ecosystems and atmospheric processes, and why we must care about biodiversity and nature conservation,” Boyer emphasized. The study’s findings were published in the journal Communications Earth & Environment.