Media release

From: Springer Nature

Penguin guano may help reduce effects of climate change in Antarctica

Ammonia released from penguin guano may help to reduce the effects of climate change in the Antarctic by contributing to increased cloud formation, according to an analysis published in Communications Earth & Environment. The conclusion is the result of measurements taken downwind of a colony of Adelie penguins (Pygoscelis adeliae).

Antarctic ecosystems are facing significant pressures because of human-driven climate change, including a recent decreasing trend in the area covered by sea ice. Penguins are key species in the Antarctic ecosystem whose habitat is threatened by this ongoing ice loss. They are also, along with other seabirds, major emitters of ammonia in the region. Ammonia can increase cloud formation by reacting with gases containing sulphur to increase the creation of aerosols — particles which give water vapour a surface to condense upon, leading to cloud formation. The resulting clouds can act as insulating layers in the atmosphere, often helping to reduce surface temperatures and subsequently affecting the extent of sea ice coverage. However, the specific interaction between penguins and the Antarctic climate is currently poorly understood.

Matthew Boyer, Mikko Sipilä, and colleagues measured the concentration of ammonia in the air at a site near Marambio Base, Antarctica, between 10 January and 20 March 2023. They observed that when the wind blew from the direction of a 60,000-individual Adelie penguin colony around 8 kilometres away, the ammonia concentration increased to as high as 13.5 parts per billion — more than 1,000 times higher than the baseline value (less than 10.5 parts per trillion). Even after the penguins migrated from the area towards the end of February, the ammonia concentration was still more than 100 times higher than the baseline, as the penguin guano left at the colony site continued to emit the gas.

To confirm that the increase in ammonia concentration affected aerosol particle concentration, the authors recorded several additional atmospheric measurements on a single day. When the wind blew from the penguin colony, the number, and size, of aerosol particles recorded at the site sharply increased, with the authors later (approximately three hours after the wind changed) observing a period of fog which they say was likely a result of the increased aerosol particle concentration.

The results suggest that penguin guano may be helping to reduce the effects of climate change on the penguins’ own habitat of Antarctica. The authors say that their work emphasises the importance, and benefits, of protecting seabirds and their habitats from the effects of climate change.