|[ The once-thickest sea ice has gone - click on images to enlarge ]|
The loss of this sea ice indicates that the buffer is gone. Sea ice acts as a buffer that absorbs heat, while keeping the temperature at the freezing point of water, about zero degrees Celsius. As long as there is sea ice in the water, this sea ice will keep absorbing heat, so the temperature doesn't rise at the sea surface.
Once the buffer is gone, further energy that enters the Arctic Ocean will go into heating up the water. The amount of energy absorbed by melting ice is as much as it takes to heat an equivalent mass of water from zero to 80°C.
|[ The Latent Heat Buffer has gone, feedback #14 on the Feedbacks page ]|
|[ Albedo Change, feedback #1 on the Feedbacks page ]|
Numerous feedbacks are associated with sea ice loss. As the temperature difference between the Arctic and the Equator decreases, changes are taking pace to the Jet Stream that in turn trigger a multitude of further feedbacks, such as more extreme weather and a more scope for heat to enter the Arctic Ocean (see feedbacks page).
A further huge danger is that, as warming of the Arctic Ocean continues, heat will reach methane hydrates at the seafloor of the Arctic Ocean, causing them to get destabilized and release methane.
Adding up all warming elements associated with disappearance of the sea ice could result in additional global warming many times as much as the current global warming, all in a few years time.
|[ Seafloor methane, feedback #2 on the Feedbacks page ]|
Meanwhile, for the first time in human history, mean global methane levels as high as 1900 ppb have been recorded. The measurements were recorded by the MetOp-1 satellite on the morning of August 22, 2018, at 280 mb, 266 mb, 307 mb and 321 mb, as shown by the images below.
At 293 mb, MetOp-1 recorded an even higher level, i.e. mean global methane level was 1901 ppb on the morning of August 22, 2018.
The situation is dire and calls for comprehensive and effective action, as described in the Climate Plan.
• It could be unbearably hot in many places within a few years time
• Latent Heat
• Albedo and more
• How much warming have humans caused?
• The Threat
• Climate Plan