Bird poop helps cool the Arctic in summer, new study finds
Seabird researcher calls discovery of birds' impact on climate 'mind-boggling'
A study released this month shows bird poop might be cooler than you think.
Thousands of tonnes of seabird feces deposited in the Canadian Arctic help keep the Arctic climate cooler in the summer, according to one of the study's lead authors Greg Wentworth, an atmospheric scientist with Alberta Environment and Parks.
Wentworth said he was surprised when his team measured an unexpectedly high concentration of ammonia in the "pristine, summertime Arctic atmosphere" back in July 2014.
"We were scratching our heads a little bit."
Turns out, it was courtesy of the tens of millions of seabirds that migrate to the Arctic every summer.
Their guano — or poop — produces enough ammonia to affect the atmosphere.
"And this is important because no one had actually tried to measure ammonia in the Canadian Arctic before," said Wentworth.
Ammonia — a prevalent chemical in lower parts of Canada from agriculture and industrial emissions — is an anomaly in the Far North, he said.
How does it work?
Seabirds have a very nitrogen-rich diet and their feces, through a breakdown of particles, releases ammonia into the air.
The ammonia then reacts with other particles and gases and forms "tiny liquid and solid droplets suspended in the atmosphere," said Wentworth.
These particles can grow and affect cloud formation.
"Typically, the more of these particles you have, the brighter the clouds are. And brighter clouds reflect more sunlight," said Wentworth.
Wentworth called it a "brighter umbrella" where bird-poop-infused clouds reflect sunlight away from the Arctic.
"So the birds provide this key link that sort of kick starts this poop-to-particle-to-cloud chemistry… and as we found, had a cooling effect on the Arctic."
Small cooling effect
But bird poop won't solve global warming, said Wentworth.
"It's not like it's going to mitigate the warming in the Arctic or solve it," he said. "But it's an important factor and now birds are in the equation."
The estimated 40,000 tonnes of seabird excrement each summer "in the grand scheme of things, isn't very much," said Wentworth. It has an impact of -0.5 watts per square metre; to put that into perspective, the natural greenhouse effect is +150 watts per square metre, said Wentworth.
"So it's a small cooling effect, but it's a significant one especially for a region that's experiencing such a rapid warming as the Arctic."
'Dire situation' for birds with warming climate
"This [study] goes beyond our previous understanding. This is revolutionary," said Ian L. Jones, a seabird researcher and a professor of biology at Memorial University.
"Holy moly. Seriously, holy moly."
Jones said although he's lived and worked around seabird colonies for years, this chemical cooling effect has never occurred to him before.
"People, when we visit seabird colonies, are kind of wincing at all the ammonia smell," he said, describing the odour as unpleasant and strong, comparing it to "stale urine."
"This study is mind boggling because it shows that the impact of the birds go beyond biological nature, and affects the climate. It emphasizes the need to drastically understand Arctic animals and birds."
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But Jones warned that this slight cooling effect may be short-lived if rapid warming of the Arctic continues. Seabird populations have adapted to the cold and a warmer Arctic will make the area unsuitable for the birds to live in.
"It's a dire situation," he said.
"They don't have a mechanism for 'Oh, it's warm here so we're going to move.' So they stick it out where they are and they suffer death by heat exhaustion.
"The birds are in deep trouble. So this effect described in this paper will decline."
The excrement of other Arctic animals like caribou and muskox may or may not contribute to the ammonia levels in the Arctic, said Wentworth. Further studies must be done to measure their effect on the climate, he said.
with files from Garrett Hinchey, Loren McGinnis