Penguin droppings ‘delaying' climate change

Telegraph

22-05-2025

Penguin droppings are helping to undo some of the effects of climate change, a study has found.
Excrement of the marine birds contains a high amount of ammonia which rises into the atmosphere and helps form clouds that deflect sunlight and lower temperatures.
Cloud cover has an insulating effect on the immediate environment and in the Antarctic region is thought to have a beneficial impact on the amount of sea ice cover.
Scientists have found that the guano gas reacts with sulphur in the atmosphere to produce aerosols which then attract water vapour to form fog and clouds.
Data from a research station near Marambio Base in Antarctica which was close to a colony of 60,000 Adélie penguins in early 2023 was tracked by researchers at the University of Helsinki.
Analysis of ammonia levels over time revealed that when the site was upwind of the colony there was only a small amount of ammonia detectable.
However, when the wind carried from the penguins to the sensors, ammonia levels jumped 1,000 times higher.
On one day during the study, Feb 1 2023, there was a particularly high amount of ammonia over the research station about five miles from the colony, due to favourable winds.
Data show that for about six hours the amount of particles in the air increased and then a fog was created.
'The chemical composition of the cloud droplet residuals was composed almost solely of ammonia sulphate, which confirms the participation of ammonia sourced from the penguins,' the scientists write.
They add: 'Given that penguin colonies span the coast of Antarctica and that they leave guano/nutrient-rich soils that continue to emit ammonia after migration, we estimate that penguins provide a substantial source of ammonia that enhances particle concentrations across the entire coastal Antarctic region.'
The scientists say that the environmental benefit of the faeces-driven cloud formation is likely to be seen the most around the coastal areas inhabited by the birds, but will also spread further afield.
Ammonia has a short lifespan in the atmosphere but is released from guano over several days, providing a long-term source, the scientists found, which persists after the penguins have migrated.
The researchers say: 'These newly formed particles could be further transported over parts of the Southern Ocean and continental Antarctica on this timescale, which could subsequently affect aerosol concentrations over the larger Antarctic region, including further inland where aerosol sources are limited.
'This suggests that coastal penguin/bird colonies could also comprise an important source of aerosol away from the coast.'
The UK government body, the Advanced Research and Invention Agency, has been looking at ways to form clouds to dim sunlight, having announced £57 million being allocated for 21 'climate cooling' projects, including five outdoor field trials.
The penguin study is published in the journal Communications Earth & Environment.