Science Snippets: Ice Melting, North and South

Draft script:

According to a headline at earth.com, Glacier melt in Alaska is accelerating at an alarming rate. The article was published 2 July 2024. Here’s the lede: “Recent research led by experts at Newcastle University indicates that glacier melt on Alaska’s Juneau Icefield is accelerating faster than previously thought, potentially reaching an irreversible tipping point sooner.”

Several key points are made in the article at earth.com: (1) “Initially, the glacier volume loss was consistent at 0.65-1.01 km³ per year until 1979. From 1979 to 2010, this rate increased to 3.08-3.72 km³ per year.” This more than tripling of glacier volume loss is an astonishing increase in a short period of time. Worse yet, “the most alarming increase occurred between 2010 and 2020, when the rate of ice loss doubled to 5.91 km³ per year.” In other words, the rate of glacier volume loss more than tripled, and then it nearly doubled. (2) “Overall, the total ice loss across the Juneau Icefield between 1770-2020 … equated to just under a quarter of the original ice volume.” (3) “100% of glaciers mapped in 2019 have receded relative to their position in 1770, and 108 glaciers have disappeared completely.” (4) The lead author of an associated paper in Nature Communications said, “It’s incredibly worrying that our research found a rapid acceleration since the early 21st century in the rate of glacier loss across the Juneau icefield. As glacier thinning on the Juneau plateau continues and ice retreats to lower levels and warmer air, the feedback processes this sets in motion is likely to prevent future glacier regrowth, potentially pushing glaciers beyond a tipping point into irreversible recession.” (5) According to the paper in earth.com, the peer-reviewed, open-access paper in Nature Communications took issue with an important point. The Discussion section of the peer-reviewed paper argued that current published projections for the Juneau icefield “suggest a linear rate of volume loss to 2040 AD and acceleration only after 2070 AD.” As pointed out in the earth.com article, “current published projections for the Juneau icefield that suggest ice volume loss will be linear until 2040 … may need to be updated to reflect the processes detailed in this latest study.”

You think so? The Juneau icefield is obviously undergoing nonlinear change already. As with dozens of other phenomena throughout the world, nonlinear change dominates. Let’s call it what it is: exponential change. Earth is undergoing exponential climate change, and this pattern is matched by exponential changes in many phenomena throughout the world.

Turning from the North Pole to the South Pole, we find a 3 July 2024 article in Popular Mechanics titled Tipping Point in Antarctica Could Trigger Unstoppable Ice Melting. Here’s the subhead: “Rapid changes. Increased sea levels. Nothing good.”

The article in Popular Mechanics begins with three bullet points: (1) “For years, the Greenland and Antarctic ice sheets have been melting faster than predicted by the Intergovernmental Panel on Climate Change.” (2) “A new study published by scientists at the British Antarctic Survey says that insidious ground-based ice melt, caused by warm water seeping between the land and ice sheet, could be the explanation we’ve been looking for.” (3) “Understanding how quickly these ice sheets are melting is vital for preparing coastal communities threatened by sea level rise.”

My brief comment on each of these three bullet points: (1) “For years, the Greenland and Antarctic ice sheets have been melting faster than predicted by the Intergovernmental Panel on Climate Change.” Really? The IPCC, which was designed to fail when it was created by the Ronald Reagan administration, has actually failed? I have pointed to several other failures by the IPCC with my previous work. Suffice it to say that the replacement of the Advisory Group on Greenhouse Gases with the IPCC was, and is, and terrible idea for those of us interested in taking an evidentiary approach.

My brief comment on bullet point number two, which reads “A new study published by scientists at the British Antarctic Survey says that insidious ground-based ice melt, caused by warm water seeping between the land and ice sheet, could be the explanation we’ve been looking for.” If we’re looking for an explanation beyond abrupt, irreversible climate change, then I think we’re wasting time looking for symptoms, rather than seeking the underlying explanation.

My even briefer comment on bullet point number three, which reads “Understanding how quickly these ice sheets are melting is vital for preparing coastal communities threatened by sea level rise.” Duh! However, I doubt sea level rise will be the biggest challenge we face in the months and years ahead.

The article in Popular Mechanics points to a peer-reviewed, open-access paper in Nature Geoscience published 25 June 2024. The peer-reviewed paper is titled Tipping point in ice-sheet grounding-zone melting due to ocean water intrusion. The abstract of the peer-reviewed paper includes this information: “We find that increases in ocean temperature can lead to a tipping point being passed, beyond which ocean water intrudes in an unbounded manner beneath the ice sheet, via a process of runaway melting.” I’ll interrupt my reading of the Abstract to point out that the IPCC concluded that “increases in ocean temperature can lead to a tipping point being passed” by pointing out that a tipping point had already been passed. The IPCC reached this conclusion five years ago this month with its IPCC Special Report on the Ocean and Cryosphere in a Changing Climate. If you’re publishing a paper about an oceanic tipping point, you might want to read some relevant literature.

Back to the peer-reviewed, open-access paper in Nature Geoscience. “[T]his tipping point may not be easily detected with early warning indicators. … Our results point towards a stronger sensitivity of ice-sheet melting, and thus higher sea-level-rise contribution in a warming climate, than has been previously understood.” No, they don’t. Your results indicate something pointed out by the IPCC long ago. In addition, as I’ve pointed out repeatedly in this space, sea level rise is hardly our biggest problem. I recognize that sea level rise is important to people who live near the ocean. However, I suspect loss of habitat by other means will cause a far greater loss of humans than sea level rise.

Speaking of ice melting at the poles, let’s take a look at one plausible outcome. According to an article published by MIT News, Weaker ocean circulation could enhance CO2 buildup in the atmosphere. That’s the headline of the article at MIT News. The subtitle is “New findings challenge current thinking on the ocean’s role in storing carbon.” Here’s the lede for the article at MIT News published on 8 July 2024: “As warming weakens ocean circulation, the seas could increasingly become a source of heat-trapping gas, as new study finds.”

The article in MIT News points to a peer-reviewed, open-access paper in Nature Communications. As with the paper in MIT News, it was published on 8 July 2024. The author of the peer-reviewed paper is quoted in the MIT News article: “What we thought is going on in the ocean is completely overturned. [W]e can’t count on the ocean to store carbon in the deep ocean in response to future changes in circulation.”

The peer-reviewed paper in Nature Communications echoes the article at MIT News. The Abstract of the peer-reviewed paper includes this important line: “reduced Meridional Overturning Circulation nutrient upwelling decreases biological activity.”

You heard me correctly. A slowing of this important ocean circulation pattern decreases biological activity, even if we attempt to dump iron filings into the ocean.

Here’s an idea: Let’s not dump iron filings into the ocean. In fact, let’s not assume we can fix every single thing we destroyed. We have already destroyed habitat for many species on Earth. Let’s not assume our species is so special that we cannot join these other species. After all, as Professor and science advocate Carl Sagan famously said: “By far most of the species of life that have ever existed are now extinct. Extinction is the rule. Survival is the exception.”