The April 2024 temperature is 1.32°C higher than 1951-1980, as illustrated by the above image, adapted from NASA. Local anomalies are as high as 6.2°C.
The image below, created with NASA Land+Ocean monthly mean global temperature anomalies versus a 1900-1923 custom base, further adjusted by 0.99°C to reflect ocean air temperatures, higher polar anomalies and a pre-industrial base.
[ from earlier post ] |
There is no single feedback behind the recent steep rise and acceleration, instead there are numerous non-linear, self-reinforcing feedbacks that can all contribute, interact and start to kick in with greater ferocity, amplifying and further accelerating the rise.
Furthermore, developments such as the reduction in sulfur emissions over the past few years are further pushing up the temperature rise. Altogether, the temperature rise may exceed 18°C from pre-industrial by as early as 2026, as discussed at the Extinction page.
The above image shows that the North Atlantic sea surface temperature was 21.4°C on May 12, 2024. High North Atlantic sea surface temperatures spell bad news for the Arctic, as much ocean heat gets pushed toward the Arctic from the North Atlantic. North Atlantic sea surface temperatures are now getting pushed up strongly from their annual minimum, in line with seasonal changes. Ominously, a peak of 25.4°C was reached in August 2023, i.e. 4°C higher than the current temperature.
One tipping point that threatens to get crossed is loss of Arctic sea ice. Loss of Arctic sea ice comes with albedo change, which constitutes a huge self-reinforcing feedback loop, i.e. the more sea ice disappears, the more sunlight gets absorbed by the Arctic Ocean, further accelerating sea ice melting, while less sunlight gets reflected back into space.
[ Albedo change, from the Albedo page ] |
The amount of energy absorbed by melting ice is as much as it takes to heat up an equivalent mass of water from zero to 80°C. Loss of the latent heat buffer therefore constitutes a tipping point, i.e. once crossed, the Arctic Ocean will heat up at an accelerating pace.
Seafloor methane constitutes a second tipping point. When methane escapes from hydrates that get destabilized by rising temperatures, the methane will expand to 160 times its previous volume and enter the atmosphere with force. Without the buffer constituted by thicker sea ice, an influx of ocean heat could cause large-scale destabilization of hydrates contained in sediments at the seafloor of the Arctic Ocean, resulting in eruptions of huge amounts of methane.
[ from earlier post ] |
Links
• NASA - datasets and images
https://data.giss.nasa.gov
https://climatereanalyzer.org
https://pulse.climate.copernicus.eu
• Pre-industrial
https://arctic-news.blogspot.com/p/pre-industrial.html
• Extinction
https://arctic-news.blogspot.com/p/extinction.html
https://arctic-news.blogspot.com/p/jet-stream.html
• Cold freshwater lid on North Atlantic
https://arctic-news.blogspot.com/p/cold-freshwater-lid-on-north-atlantic.html
https://arctic-news.blogspot.com/2017/01/arctic-ocean-feedbacks.html
• Arctic sea ice set for steep decline
https://arctic-news.blogspot.com/2024/03/arctic-sea-ice-set-for-steep-decline.html
• Did the climate experience a Regime Change in 2023?
• Transforming Society
https://arctic-news.blogspot.com/2022/10/transforming-society.html
• Climate Plan
https://arctic-news.blogspot.com/p/climateplan.html
• Climate Emergency Declaration
https://arctic-news.blogspot.com/p/climate-emergency-declaration.html