The Transpolar Drift is faltering – and sea ice is now melting before it can leave the nursery

The Transpolar Drift is faltering – and sea ice is now melting before it can leave the nursery

SOURCE: AWI DATE: April 2, 2019 SNIP: The shallow Russian shelf or marginal seas of the Arctic Ocean are broadly considered to be the ‘nursery’ of Arctic sea ice: in winter, the Barents Sea, Kara Sea, Laptev Sea and East Siberian Sea constantly produce new sea ice. This is due to extremely low air temperatures down to minus 40 degrees Celsius, and a strong offshore wind that drives the young ice out to the open sea. In the course of the winter, the sea ice is eventually caught up in the Transpolar Drift, one of the two main currents in the Arctic Ocean. In two to three years’ time, it transports the ice floes from the Siberian part of the Arctic Ocean, across the Central Arctic, and into the Fram Strait, where it finally melts. Two decades ago, roughly half the ice from Russia’s shelf seas made this transarctic journey. Today only 20 percent does; the other 80 percent of the young ice melts before it can become a year old and reach the Central Arctic. The ice now leaving the Arctic through the Fram Strait is, on average, 30 percent thinner than it was 15 years ago. The reasons: on the one hand, rising winter temperatures in the Arctic and a melting season that now begins much earlier; on the other, this ice is no longer formed in the shelf seas, but much farther north. As a result, it has far less time to drift through the Arctic and grow into thicker pack...
Sea ice in the central Arctic should be growing. It’s not.

Sea ice in the central Arctic should be growing. It’s not.

SOURCE: Mashable DATE: October 11, 2018 SNIP: In the deep middle of the remote Arctic Ocean, things are amiss. With the passage of summer, the ice — diminished by the warm season — is expected to regrow as frigid temperatures envelope the Arctic. But, this year, it’s not. Specifically, sea ice in the Central Arctic basin — a massive region of ocean some 4.5 million square kilometers in size — hasn’t started its usual rapid expansion, and unusually warm temperatures in both the air and the ocean are largely to blame. “For the most part, Arctic sea ice normally begins rapidly refreezing this time of year,” Zack Labe, a climate scientist and Ph.D. candidate at the University of California Irvine, said over email. In mid-October, the temperatures here should be plummeting. But they’ve gone up. “Both the ocean and atmosphere are warmer than usual,” said Lars Kaleschke, an Arctic scientist at the University of Hamburg’s Center for Earth System Research and...
Arctic’s strongest sea ice breaks up for first time on record

Arctic’s strongest sea ice breaks up for first time on record

SOURCE: The Guardian DATE: August 21, 2018 SNIP: The oldest and thickest sea ice in the Arctic has started to break up, opening waters north of Greenland that are normally frozen, even in summer. This phenomenon – which has never been recorded before – has occurred twice this year due to warm winds and a climate-change driven heatwave in the northern hemisphere. One meteorologist described the loss of ice as “scary”. Others said it could force scientists to revise their theories about which part of the Arctic will withstand warming the longest. The sea off the north coast of Greenland is normally so frozen that it was referred to, until recently, as “the last ice area” because it was assumed that this would be the final northern holdout against the melting effects of a hotter planet. But abnormal temperature spikes in February and earlier this month have left it vulnerable to winds, which have pushed the ice further away from the coast than at any time since satellite records began in the 1970s. Freakish Arctic temperatures have alarmed climate scientists since the beginning of the year. During the sunless winter, a heatwave raised concerns that the polar vortex may be eroding. This includes the Gulf Stream, which is at its weakest level in 1,600 years due to melting Greenland ice and ocean warming. With lower circulation of water and air, weather systems tend to linger...
Barents Sea seems to have crossed a climate tipping point

Barents Sea seems to have crossed a climate tipping point

SOURCE: Ars Technica DATE: June 26, 2018 SNIP: Many of the threats we know are associated with climate change are slow moving. Gradually rising seas, a steady uptick in extreme weather events, and more all mean that change will come gradually to much of the globe. But we also recognize that there can be tipping points, where certain aspects of our climate system shift suddenly to new behaviors. The challenge with tipping points is that they’re often easiest to identify in retrospect. We have some indications that our climate has experienced them in the past, but reconstructing how quickly a system tipped over or the forces that drove the change can be difficult. Now, a team of Norwegian scientists is suggesting it has watched the climate reach a tipping point: the loss of Arctic sea ice has flipped the Barents Sea from acting as a buffer between the Atlantic and Arctic oceans to something closer to an arm of the Atlantic. The Norwegian work doesn’t rely on any new breakthrough in technology. Instead, it’s built on the longterm collection of data. The Barents Sea has been monitored for things like temperature, ice cover, and salinity, in some cases extending back over 50 years. This provides a good baseline to pick up longterm changes. And, in the case of the Barents Sea in particular, it’s meant we’ve happened to have been watching as a major change took place. [N]ot only have we discovered a climate tipping point, but we’ve spotted it after the system has probably already flipped into a new regime. It also provides some sense of what to...
In the Arctic, the Old Ice Is Disappearing

In the Arctic, the Old Ice Is Disappearing

SOURCE: New York Times DATE: May 14, 2018 SNIP: In the Arctic Ocean, some ice stays frozen year-round, lasting for many years before melting. But this winter, the region hit a record low for ice older than five years. This, along with a near-record low for sea ice over all, supports predictions that by midcentury there will be no more ice in the Arctic Ocean in summer. As darker, heat-absorbing water replaces reflective ice, it hastens warming in the region. Older ice is generally thicker than newer ice and thus more resilient to heat. But as the old ice disappears, the newer ice left behind is more vulnerable to rising temperatures. “First-year ice grows through winter and then to up to a maximum, which is usually around in March,” said Mark A. Tschudi, a research associate at the Colorado Center for Astrodynamics Research at the University of Colorado, Boulder. “As summer onsets, the ice starts to melt back.” Some of the new ice melts each summer, but some of it lingers to grow thicker over the following winter, forming second-year ice. The next summer, some of that second-year ice survives, then grows even thicker and more resilient the next winter, creating what is known as multiyear ice. Some ice used to last more than a decade. Today, Arctic sea ice is mostly first-year ice. While the oldest ice has always melted when currents pushed it south into warmer waters, now more of the multiyear ice is melting within the Arctic Ocean, leaving more open water in its wake. “I’ve been on record saying that it may be 2030 that...