Climate change triggers a chain reaction that threatens the heart of the Pacific

Climate change triggers a chain reaction that threatens the heart of the Pacific

SOURCE: Omaha World-Herald DATE: November 16, 2019 SNIP: The salmon catch is collapsing off Japan’s northern coast, plummeting by about 70 percent in the past 15 years. The disappearance of the fish coincides with another striking development: the loss of a unique blanket of sea ice that dips far below the Arctic to reach this shore. The twin impacts – less ice, fewer salmon – are the products of rapid warming in the Sea of Okhotsk, wedged between Siberia and Japan. The area has warmed in some places by as much as 3 degrees Celsius (5.4 degrees Fahrenheit) since preindustrial times, making it one of the fastest-warming spots in the world, according to a Washington Post analysis of data from the nonprofit organization Berkeley Earth. That increase far outstrips the global average and exceeds the limit policymakers set in Paris in 2015 when they aimed to keep Earth’s average temperature rise “well below” 2 degrees Celsius (3.6 degrees Fahrenheit). The rising temperatures are starting to shut down the single most dynamic sea ice factory on Earth. The intensity of ice generation in the northwestern Sea of Okhotsk exceeds that of any single place in the Arctic Ocean or Antarctica, and the sea ice reaches a lower latitude than anywhere else on the planet. Its decline has a cascade of consequences well beyond Japan as climate dominoes begin to fall. When sea ice forms here, it expels huge amounts of salt into the frigid water below the surface, creating some of the densest ocean water on Earth. That water then sinks and travels east, carrying oxygen, iron and other key...
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...