Narwhals can be disturbed faraway noises
A new study from Greenland found the whales reacted to noises from as far away as 20 or 30 kilometers.
A new study shows that narwhals are disturbed by noise originating as far as 20 to 30 kilometers away, reports Greenland national broadcaster KNR.
The noise may disturb them so much that they avoid foraging, according to a recent study from Copenhagen University and Greenland’s Nature Institute.
[Noise from ships in Nunavut waters could change whale behavior, research suggests]
Tests were conducted in East Greenland in which scientists spent one week conducting tests using a ship engine and a seismic air cannon, which is used in petroleum exploration. In one case, the scientists observed an influence from noise originating 40 kilometers away.
“The narwhals’ reactions indicated that they get scared and stressed,” marine biologist Outi Tervo of Greenland’s Nature Institute, one of the scientists behind the study, told KNR. “They stop transmitting clicking sounds that they use when the forage, they no longer dive deep, and the swim close to the coast, a thing they would otherwise only do when feeling threatened by killer whales. This behavior means they have no means of finding food as long as the noise goes on.”
The Arctic’s highest latitudes saw a huge spike in lightning last year
There was almost twice as much lightning north of 80 degrees in 2021 as in the previous nine years combined, a Finnish firm said.
Scientists have long known that lightning is becoming more common in the Arctic, but a new report shows that the trend is increasing especially fast at the highest latitudes.
In 2019, a dramatic set of lightning event near the North Pole made headlines.
Then in the spring of 2021, a paper reported that lightning had tripled in the Arctic over the previous decade — an increase that climate scientists had predicted would come with rapid warming.
As if on cue, later that summer, unusual lightning events struck over sea ice off Northern Alaska and near Iqaluit in Nunavut.
Now, the Finnish weather information company Vaisala, it its annual lightning report, has documented a dramatic increase in lightning at the highest latitudes.
In 2021 there were 7,238 lightning events north of 80 degrees North latitude, the company said. That’s almost twice as many as in the preceding nine years combined. Even further north — north of 85 degrees — the company recorded a record high 634 events. (Areas of the Arctic further south, where lightning is a little more common, didn’t see such dramatic increases.)
The spike was linked to “a series of low pressure systems exiting northern Siberia and crossing the Arctic Ocean,” the company’s lightning applications manager, Chris Vagasky, told Gizmodo, combining high temperatures and humidity to create conditions more like those “seen over the Great Plains of the United States during severe weather outbreaks.”
Because the thunderstorms that generate them require heat to form, lightning strikes are one variable scientists use to track climate change.
It’s long been known that the Arctic is warming faster than the rest of the planet.
Early in 2021, the Arctic Council confirmed that the Arctic is warming three times as fast as the global average — but by last month a new study revised that figure upward again, to a staggering four times as fast.
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