Here is Margo’s latest video.
According to many, a Blue Ocean Event starts once Arctic sea ice extent falls below 1 million km².
So let’s have another look at how much of the above 4.912 million km² can be regarded as sea ice, by using the NSIDC map with sea ice concentration as a guide.
The roughly-sketched outline drawn over the NASA map below indicates that there may only have been some 991 thousand km² of concentrated sea ice left on September 6, 2022 (inset shows NSIDC sea ice concentration for the day).
As said, it’s a rough sketch, so some cells with a higher concentration of sea ice may have been left out. Having said that, we’re currently in the depth of a persistent La Niña and the associated lower air temperatures contribute to a relatively larger sea ice extent than would otherwise be the case.
In conclusion, depending on what is counted as sea ice, we could already be experiencing a Blue Ocean Event right now.
- a strong El Niño triggers:
- further decline of the Arctic sea ice, with loss of the latent heat buffer, combined with
- associated loss of sea ice albedo and
- destabilization of seafloor methane hydrates, causing eruption of vast amounts of methane that further speed up Arctic warming and cause
- rapid thawing of terrestrial permafrost, resulting in even more emissions,
- while the Jet Stream gets even more deformed, resulting in more extreme weather events
- causing forest fires, at first in Siberia and Canada and
- eventually also in the peat fields and tropical rain forests of the Amazon, in Africa and South-east Asia, resulting in
- decline of snow and ice on mountains, at first causing huge flooding, followed by
- drought, heatwaves and urban collapse,
- collapse of the Greenland and West-Antarctic ice sheets,
- falling away of aerosol masking as civilization grinds to a halt,
- further heating due to gases and particulates from wood and waste burning and biomass decomposition, and
- further heating due to additional gases (including water vapor), cirrus clouds, albedo changes and heat rising up from oceans.
Importantly, depicted above is only one scenario out of many. Things may eventuate in different order and occur simultaneously, i.e. instead of one domino tipping over the next one sequentially, many events may occur simultaneously and reinforce each other. Further events and developments could be added to the list, such as ocean stratification and stronger storms that can push large amounts of warm salty water into the Arctic Ocean.
Here is another example of such a scenario. Recent studies indicate that human-caused climate change will soon increase El Niño frequency and intensity. Accordingly, the upcoming El Niño may well be strong. We’re currently in the depth of a persistent La Niña, which suppresses the temperature rise, whereas the opposite occurs during El Niño, which amplifies the temperature rise, and this especially affects the Arctic, which is already heating up much faster than the rest of the world. Also, the upcoming El Niño may very well coincide with a peak in sunspots in 2025, further pushing up temperatures.
Furthermore, the narrowing temperature difference between the Arctic and the Tropics will further deform the Jet Stream and in turn cause more extreme weather, leading to more loss of sea ice and thus of its capacity to reflect sunlight and act as a buffer against incoming ocean heat.
A huge amount of heat has built up in the North Atlantic off the coast of North America, as illustrated by the image on the right.
As discussed in an earlier post, rising temperatures result in stronger winds along the path of the Gulf Stream that can make huge amounts of warm, salty water travel from the Atlantic Ocean toward the Arctic and reach shallow parts of the Arctic Ocean such as the East Siberian Arctic Shelf (ESAS), where most of the sea is less than 50 m deep. The danger is illustrated by the Argo float compilation below.
The image below, from an earlier post, shows annual global mean methane with a trend added that points at a methane rise that could in 2028 represent a forcing of 780 ppm CO₂e (with a 1-year GWP of 200).
NOAA’s globally averaged marine surface mean for April 2022 was 1909.9 ppb. The above image shows that, on September 4, 2022 am, the MetOp satellite recorded a mean methane concentration of 1904 ppb at 586 mb, which is close to sea level. At 293 mb, however, the MetOp satellite recorded a mean of 1977 ppb, while at 218 mb it recorded a peak of 2805 ppb.
Such high methane levels could be caused by destabilization of methane hydrates at the seafloor of the Arctic Ocean, with large amounts of methane erupting (increasing 160 x in volume) and rising up at accelerating speed through the water column (since methane is lighter than water), concentrated in the form of plumes, which makes that less methane gets broken down in the water by microbes and in the air by hydroxyl, of which there is very little in the Arctic in the first place. Such a methane eruption entering the atmosphere in the form of a plume can be hard to detect as long as it still doesn’t cover enough of the 12 km in diameter footprint to give a pixel the color associated with high methane levels.
• NASA Worldview
• More Frequent El Niño Events Predicted by 2040
Cutting-edge models predict that El Niño frequency will increase within 2 decades because of climate change, regardless of emissions mitigation efforts.
• Emergence of climate change in the tropical Pacific – by Yun Ying et al.
• Monitoring of atmospheric composition using the thermal infrared IASI/MetOp sounder – by C. Clerbaux et al.
https://arctic-news.blogspot.com/p/albedo.html• Latent Heat
• Jet Stream
• Blue Ocean Event
• Climate Plan