Whale songs and war: The less talked-about climate change impacts

Near Antarctica, whales are singing in deeper tones to cut through the noise of melting icebergs. In California, a big college football rivalry game was postponed until Saturday because of smoky air from wildfires. And Alaskan shellfish were struck by an outbreak of warm water bacteria.

That's global warming in action.

Climate change is more than heat waves, hurricanes, floods, droughts, sea level rise, melting ice and ever-increasing temperatures.

Sometimes global warming has a hand — directly or indirectly — in something quirky, such as the pitch change in five baleen whale populations in the Southern Ocean. It can be annoying, such as having to reschedule the Big Game between California and Stanford, or seeing plants bloom too early in the spring.

More often the influence of climate change is ominous, like oceans becoming more acidic and eating away at clam shells and coral reefs, which already got bleached by warmer waters.

Or even out-of-place and dangerous, like the Vibrio bacteria outbreak in Alaska or once-tropical, disease-carrying mosquitoes arriving in Canada.

It could be a bit unexpected, like a study linking warmer climate to a rise in winter crimes in the United States. Northeastern University criminologist James Fox says that actually makes sense because more people outside means more opportunity for foul play.

And climate change has altered global politics. Numerous studies have said it was a factor in record-setting drought in Syria — one of several causes of the country's civil war that triggered a massive refugee crisis.

The military calls this a multiplier effect. Problems combine, pile up and worsen each other. Climate change does that, even in matters of national security, said Richard Alley, a climate scientist at Pennsylvania State University.

"Climate change didn't cause the Syrian civil war" but in a place that's unhappy, a drought arrives, farmers move to an overcrowded city and problems multiply and lead to war, Alley said. "It was the straw that broke the camel's back."

Conflict over climate change impacts is not confined to Syria, says University of Oklahoma meteorology professor Renee McPherson. It also applies to thousands of Nigerians "killed in conflicts between farmers and cattle herders who are competing for diminishing water supplies and fertile lands," she said.

"It's like a domino effect," said University of Hawaii geographer Camilo Mora. "You go three steps backward and you realize that climate change was part of the equations."

Mora scoured scientific literature to see how often global warming influenced some of society's ills and came up with 467 examples. Australian underground electrical transmission wires, for example, short-circuited because of heat and planes were grounded in Arizona because hotter air is thinner, making take-offs and landings more difficult.

"The laundry list of cases is just mind-blowing," Mora said.

Messing with timing of nature

A changing planet has messed with the timing of nature.

"There are hundreds of changes of the flowering of plants, the leafing out of trees, the migrations of birds" that can be attributed to climate change, said Boston University biologist Richard Primack. 

And when that happens, sometimes it creates "mismatches."

In Europe, for instance, oak trees now leaf earlier. Caterpillars hatch and eat leaves earlier. But birds migrate based on hours of daylight while insects emerge according to temperature, said climate scientist Jennifer Francis of the Woods Hole Research Center.

So the birds show up late for dinner and may have little to eat.

And in maple trees, the "whiplash" between cold and hot weather is "screwing up the sap flow," Francis said. 

A study found the weather changes, including drier conditions, and more nitrogen from human activities are stunting maple growth, which can affect syrup production. 

Global warming has changed how some male whales attract females.

Jean-Yves Royer, a geophysicist at the French National Centre for Scientific Research, and colleagues compared male baleen whale songs from 2002 to 2015 and found the sound frequency changed in areas where icebergs melt due to warmer water and air. When icebergs melt, that's the loudest sound around, he said.

So the whales deepen their song, Royer said, to penetrate through the sound of melting ice.

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