Kategorie: News
Heat wave leads to mass deaths in the sea
The western province of Canada, British Columbia, has been hit by a heat wave in recent weeks. The record-breaking temperature of almost 50 degrees Celsius in the town of Lytton led to a major fire that claimed the entire town. In the province, 500 people died. Hundreds of fires raged in the forests. But also on the coast, temperatures were measured above 45-degree mark....
The effects of the heat wave in coastal waters are dramatic, according to initial studies. According to experts, the high temperatures would have triggered a mass die-off in British Columbia waters. According to marine biologist Christopher Harley of the University of British Columbia, up to one billion marine creatures are believed to have died.
Harley told the Guardian about a walk along the coast near the major city of Vancouver: "The stench of rotting shells has been overwhelming, the beach littered with empty shells. In the shallow water, the remains of snails, starfish and clams were rotting away." Colleagues had also told him of dead sea anemones, rockfish and oysters.
Implications for water quality
While the air temperature in Vancouver was 30 degrees Celsius, the rocky shore heated up to 50 degrees, he said.
Intertidal animals such as mussels, which live where land and sea meet, can endure temperatures in the high 30s for short periods of time, Harley said. But the scorching heat, combined with low tides in the middle of the afternoon, created a dangerous combination for more than six hours at a time.
"When temperatures rise above that range, conditions become hostile. A mussel on the shore in some ways is like a toddler left in a car on a hot day. They are stuck there until the parent comes back, or in this case, the tide comes back in, and there's very little they can do. They're at the mercy of the environment. And on Saturday, Sunday, Monday, during the heat wave, it just got so hot that the mussels, there was nothing they could do," said Harley.
"The mass die-off of shellfish directly impacts water quality," Harley said. "They keep the water clean so sunlight can reach the seagrass. The shellfish colonies also provided habitat for dozens of other species."
Unthinkable without climate crisis
The extreme heat of the past few days in western North America, with temperatures reaching nearly 50 degrees, would have been all but impossible without the climate crisis, according to a study. According to a high-level international group of climate researchers, global warming caused by greenhouse gases made the heat wave in Canada and the United States 150 times more likely.
The trigger for this extreme weather is a so-called heat buildup. In the coming days, an area of high pressure is again expected to build up over the western United States, forming a "heat dome". At the same time, high-altitude winds, also known as the jet stream, are currently stabilizing these extreme weather conditions for humans.
After weeks of heat, it is currently cooler again in western Canada. However, the break will only last for a short time: the next heat wave is expected as early as the upcoming weekend.