Climate Change Continues Unabated in the Arctic
Evidence continues to mount that climate change has pushed the Arctic into a new state. Skyrocketing temperatures are altering the essence of the region, melting ice on land and sea, driving more intense wildfires, altering ocean circulation and dissolving permafrost.
A new report chronicles all these changes and warns that even if the world manages to keep global warming below the targeted 2°C threshold, some of the shifts could be permanent. Among the most harrowing are the disappearance of sea ice by the 2030s and more land ice melt than previously thought, pushing seas to more extreme heights.
The findings, released Monday in the Snow, Water, Ice and Permafrost in the Arctic (SWIPA) assessment, come after a winter of extreme discontent for the region. Sea ice receded a bit in November, a rare occurrence, and hit a record-low maximum for the third year in a row. Temperatures averaged 11°F above normal, driven by sustained mild weather that was punctured by periods of almost unheard of heat when temperatures reached up to 50°F above normal.
The decline of sea ice is well documented. It’s disappearing in all seasons with the fastest shrinkage in the summer months. Old ice, which has formed the bedrock of sea ice for decades, is also declining precipitously. That leaves new ice in its place and susceptible to melt.
The new analysis shows that the average number of days with sea ice cover has dropped by 10-20 days per decade since 1979. Some areas, such as the Barents and Karas seas, have seen even steeper declines. Disappearing sea ice means the darker ocean left in its wake absorbs more energy from the sun, speeding the warming in the region.
Arctic soil holds up to 50 percent of the world’s soil carbon. Rising temperatures are melting permafrost, causing it to release some of the carbon into the atmosphere.
While the carbon release so far has been relatively small, rising temperatures have the potential to rapidly reshape the landscape and speed the melt.
The biggest impact for the globe is the melt of land ice from Greenland’s massive ice sheet. It’s the biggest land ice driver of sea level rise, and it’s been melting at a quickening rate since 2011.
The SWIPA report uses new data and findings to update the Intergovernmental Panel on Climate Change sea level rise estimates made just four years ago.
If carbon emissions continue on their current trends, the report indicates 29 inches would be the low end of sea level rise estimates by 2100, roughly 9 inches higher than the minimum IPCC estimate. And that’s just the low end, with more sea level rise possible as scientists untangle the web of melting in Greenland as well as the Antarctic.
The massive rush of freshwater into the Arctic Ocean is also reshaping ocean circulation and the ecology of the region. Researchers have seen a marked slowdown in North Atlantic circulation as cold, fresh water off Greenland’s southern tip has acted as a roadblock to the currents that steer water through the region. That has the potential to mess with ocean circulation as well as weather patterns, particularly in Europe.
Research shows global warming making oceans more toxic
Climate change is predicted to cause a series of maladies for world oceans including heating up, acidification, and the loss of oxygen. A newly published study published online in the April 24 edition of the Proceedings of the National Academy of Sciences titled “Ocean warming since 1982 has expanded the niche of toxic algal blooms in the North Atlantic and North Pacific Oceans,” demonstrates that one ocean consequence of climate change that has already occurred is the spread and intensification of toxic algae.
Toxic or harmful algal blooms are not a new phenomenon, although many people may know them by other names such as red tides. These events can sicken or kill people who consume toxin-contaminated shellfish and can damage marine ecosystems by killing fish and other marine life.
The problem is worsening.
The distribution, frequency and intensity of these events have increased across the globe and this study links this expansion to ocean warming in some regions of the North Atlantic and North Pacific Oceans.
Marine algae are so tiny—50 of them side by side span only the width of a single hair—that they may seem harmless. But when billions of toxic cells come together, they can poison humans, kill marine life, and economically harm coastal communities.