Dr. from the CLICCS Climate Research Excellence Group at the University of Hamburg. As shown in a recently published study by Armineh Barkhordarian, marine heat waves will become a regular occurrence in the Arctic in the near future and will be a product of higher anthropogenic greenhouse gas emissions. .

Conditions in the Arctic have changed since 2007, as data published today (February 13) in the journal show. Nature Communication Earth and Environment. Between 2007 and 2021, there were 11 marine heat waves in the fringes of the Arctic Ocean, causing the average temperature to rise 2.2 degrees Celsius above seasonal norms and lasting an average of 37 days. Polar sea temperature has been observed every year since 2015.

The most intense heat ever in the Arctic Ocean was experienced in 2020; It lasted 103 days and the peak temperature intensity was four degrees Celsius above the long-term average. The probability of such heat occurring without the influence of anthropogenic greenhouse gases is less than one percent, Barkhordarian’s team from the CLICCS cluster of excellence estimates. So they narrowed down the number of possible climate scenarios in the Arctic. According to the research, annual sea temperature will be normal.

The Arctic has entered a new phase

In the study, Barkhordarian also proves for the first time that heat waves occur when sea ice melts early and quickly after winter. When this occurs, significant amounts of heat energy can accumulate in the water until solar radiation reaches its maximum in July.

“A new phase began in the Arctic in 2007,” says climate statistics expert Barkhordaryan. “The percentage of thin, seasonal ice is gradually increasing, while thicker, multi-year ice is decreasing.” But thin ice is less durable and melts faster, allowing incoming solar radiation to warm the water surface.

Officially, sea temperature is considered when the water surface temperature exceeds 95 percent of the last 30 years’ values ​​for at least five consecutive days.

“Not only the continued loss of sea ice, but also warmer waters could have serious negative consequences for the Arctic ecosystem,” says Barkhordaryan. Food chains may collapse, fish stocks may decline, and overall biodiversity may decline.

Are people responsible?

The study of attribution allows us to compare how the world would develop without human influence. Calculations for this study focused on the probability of each heat wave occurring in a world without anthropogenic greenhouse gases. Additionally, Barkhordarian and his team examined satellite data and used relevant climate models for their analysis.