An extreme heat event in the Arctic could cause it to reach the maximum of the extent of its ice for this year “considerably earlier” than usual, a scientist has warned.
Temperature records were broken in Norway last week, with rain falling at Svalbard airport, and unusually warm temperatures recorded in Greenland and the Russian archipelago of Franz Josef Land.
Some stations reportedly reached 30C warmer than usual for the Arctic winter. The situation was echoed at the south pole, with Concordia station, on the Antarctic Plateau, hitting a record -11.8C on Friday, more than 40C warmer than usual for this time of year.
“It is unusual to have such large departures from average occur at the same time at both poles, and in the Arctic it may have led to the maximum sea ice extent reached considerably earlier than average,” said Prof Julienne Stroeve, professor of polar observation and modelling at University College London (UCL).
Arctic sea ice extent was tracking well below the 1981 to 2010 median, according to data published by the US National Snow and Ice Data Center. On 21 March, it spread across 14.5m sq km (5.6m sq miles) compared with a 15.5m sq km historical average.
The NSIDC’s graph showed levels were also tracking below those seen in 2012, when Arctic sea ice hit its lowest ever extent. However, ice extent was greater than that seen at this time of year in 2015, 2016, 2017 and 2018, and broadly in line with levels in 2019 and 2021. Similar extents were also seen in 2005, 2006, 2007 and 2011.
Stroeve was cautious about attributing the extreme heat events to the climate crisis. “While we may expect such warming extremes to occur more frequently under climate change, it is too early to say this particular event is related to climate change,” she said. “Weather is always unpredictable. And it’s important to remember that air temperatures, while warmer than average, remain below zero.”
Dr Lisa Schipper, co-ordinating lead chapter author for the IPCC sixth assessment report and Oxford environmental research fellow, said: “The IPCC report on impacts, adaptation and vulnerability released in February underscores that the window of opportunity to act on climate is rapidly closing.
“If these extreme temperatures don’t wake people up about this urgency, at the same time as war threatens to encourage more fossil fuel extraction and use, I don’t know what will.”
