Skip to main content

Posts

Showing posts with the label Antarctica

Dire situation gets even more dire

Antarctic sea ice extent was 1.788 million km² on February 21, 2023, an all-time low in the NSIDC record. Antarctic sea ice area was 1,050,708 km² on February 22, 2023, as illustrated by the Nico Sun image below. This means that a huge amount of heat that was previously reflected back into space by the sea ice is now instead absorbed by the Southern Ocean, in a self-reinforcing feedback loop that results in further sea ice loss, in turn further speeding up the temperature rise and making the weather ever more extreme. Arctic sea ice extent was 14,271,000 km² on February 19, 2023, the third-lowest extent in the NSIDC record for the time of year, as illustrated by the above image. Global sea ice extent reached a record low of 15,500,000 km² on February 11, 2023, as illustrated by the above image. The situation is dire The dire situation is further illustrated by the image below, showing high sea surface temperature anomalies (from 1...

Antarctic sea ice in rapid decline

Earlier this year, on February 25, Antarctic sea ice extent was at an all-time record low of 1.924 million km², as the above image shows. Throughout the year, Antarctic sea ice extent has been low. On December 14, 2022, Antarctic sea ice was merely 9.864 million km² in extent. Only in 2016 was Antarctic sea ice extent lower at that time of year, and - importantly - 2016 was a strong El NiƱo year. The NOAA image on the right indicates that, while we're still in the depths of a persistent La NiƱa, the next El NiƱo looks set to strike soon. Meanwhile, ocean heat content keeps rising due to high levels of greenhouse gases, as illustrated by the image on the right.  Rising ocean heat causes sea ice to melt from below, resulting in less sea ice, which in turn means that less sunlight gets reflected back into space and more sunlight gets absorbed as heat in the ocean, making it a self-reinforcing feedback loop that further speeds up sea ice loss.  The currently very rapid decline...

Albedo loss in Antarctica

As above image shows, Antarctic sea ice extent was only 1.973 million km² on February 23, 2022, the lowest on record since satellite measurements began in 1979. Earlier, on February 20, 2022, Antarctic sea ice extent was only 1.983 million km². On February 20, 2008, it was 3.783 million km². That's a difference of 1.8 million km², or some 0.36% of the total surface of Earth  (which is 510,072,000 km²). As illustrated by above image,  adapted from IPCC AR5 , incoming solar radiation at Top Of Atmosphere (TOA) is 340.4 W/m². This 340.4 W/m² is an average. The value varies depending on the seasons, i.e. the more the surface of Earth is facing the Sun, the higher this value will be (see image below, from the insolation page ).                        The June Solstice in 2021 occurred on June 21, 2021. Another variable is how many clouds and aerosols are in the sky. Much of this radiation can be reflected or ab...

Accelerating loss of global snow and ice cover

Ocean heat is at record levels. As a result, global sea ice extent was only 16.23 million km² on February 9, 2022, the third lowest extent on record. What makes this even more worrying is that we're currently in the depth of a persistent La NiƱa. Antarctic sea ice at lowest  extent on record since start satellite measurements Ocean heat is a huge threat for Antarctica at the moment. The image below shows that Antarctic sea ice extent was only 2.091 million km² on February 16, 2022, the lowest on record since the start of satellite measurements. Ocean heat is reducing the sea ice around Antarctica and is getting underneath floating sea ice.  The Thwaites Glacier, which is on a retrograde slope, is especially vulnerable to collapse.  The Thwaites Glacier contains enough ice to raise global sea levels  by 65 cm  (25.59 inches)   if it were to completely collapse. The animation on the right, created with images from  Climate Reanalyzer , shows th...

Beyond climate tipping points

Beyond climate tipping points Greenhouse gas levels exceed the stability limit of the Greenland and Antarctic ice sheets by Andrew Glikson Abstract The pace of global warming has been grossly underestimated. As the world keeps increasing its carbon dioxide (CO₂) emissions, rising in 2018 to a record 33.1 billion ton  of CO₂ per year, the atmospheric greenhouse gas level has now exceeded 560 ppm (parts per million) CO ₂ -e quivalent , namely when methane and nitrous oxide are included. This level surpasses the stability threshold of the Greenland and Antarctic ice sheets. The term “climate change”   is thus  no longer appropriate, since what is happening in the atmosphere-ocean system, accelerating over the last 70 years or so, is an abrupt calamity on a geological dimension, threatening nature and human civilization. Ignoring what the science says, the powers-that-be are presiding over the sixth mass extinction of species, including humanity. As conveyed by leading...