Remember those questions I told you to have your kid think about in the last post? One of them was, “Can you find any reason other than climate change that can cause the oceans to warm?” How successful were they? This post may seem a little “nerdy,” but it will give your kids some ammunition if their science teacher throws anthropogenic climate change at them. (By the way, all emphases in italics are mine.)
At skepticalscience.com I read:
Data from Antarctic ice cores reveals an interesting story for the past 400,000 years. During this period, CO2 and temperatures are closely correlated, which means they rise and fall together. However, based on Antarctic ice core data, changes in CO2 follow changes in temperatures by about 600 to 1000 years, as illustrated in Figure 1 below. This has led some to conclude that CO2 simply cannot be responsible for current global warming.
I believe scientists can read thermometers. And while I believe many of
them have a predisposition, if not a solid predetermined conviction, that climate change and all its incidental effects are caused by us humans, there may be some who are honestly inquiring. Therefore, when they say the temperature of the ocean is rising, I’m willing to begin by believing them but perhaps from a different point of view. The thought that came to my mind was, if the ocean is actually warming, could heat from the earth’s core cause it? And could the oceans’ warming cause an increase in atmospheric temperature?
I validate my thought process for you with quotes from another article titled, “Antarctica’s Delicate Face.” Here are a couple for your pleasure: “When climate change causes Antarctica’s glaciers to flow out to sea faster, it’s not good news:” The article then goes on to provide some good information about other factors that could cause the glacier to melt. Then it drops back to its default position: “If now, thanks to climate change, warm seawater begins melting the glacier from underneath, the grounding line begins shifting further inland.”
Sometimes I think they get together for a Vulcan-type mind meld (which is described as “a state of deep compatibility in opinion or plans between two people” for you non-Trekkies.)
So I did some research. (Did your kids?) I found an article on the CIRES (Cooperative Institute for Research in Environmental Sciences) website that referred to a statement by Erin Pettit (you met her in the previous post): “The ice shelf acts like a brace that prevents faster flow of the upstream ice. But the brace of ice slowing Thwaites won’t last for long.”
The same article said, “Anna Crawford, a postdoctoral researcher at the University of St. Andrews, and her team use computer modelling to study ice cliff failure: a process by which ice can break off the ends of the glacier into the open ocean. The process can take on many forms, but all of them could lead to very rapid retreat of the massive glacier.”
It seems someone held CIRES’ feet to the fire because at the end of the article is the following disclaimer. I’m including the entire paragraph so I don’t seem to be misleading in any way.
STATEMENT (added 1/31/2022):
Due to some inaccuracies in media coverage following our press release, the team would like to clarify the timeline of estimated impacts from the potential collapse of Thwaites Glacier. The “chain reaction,” beginning with the potential collapse of Thwaites’ Eastern Ice Shelf would set in motion a long-term process which would eventually result in global sea level rise. While the initial steps of ice shelf collapse, glacier speed-up, and increased ice-cliff failure might happen within a couple of decades, the “2 to 10 feet” of sea level rise will require centuries to unfold—and impacts can still be mitigated depending on how humans respond in coming decades. Risk of multiple feet of sea level rise will not happen this decade (and likely not even in the next few decades). NOTE: the ITGC science community does not use the term ‘Doomsday Glacier’ when referring to Thwaites, because it gives the inaccurate impression that the disaster is sudden, and inevitable, and akin to nuclear war, which is not the case.
I admire their honesty. “. . . the “2 to 10 feet” of sea level rise will require centuries to unfold—and impacts can still be mitigated depending on how humans respond in coming decades.” You can read another opinion about this in the article “How to Scare and Deceive without Lying: JPL Cries Wolf about Polar Glacial Melt.” by E. Calvin Beisner.
A Newsweek article reports, “Scientists have discovered three channels of warm water under Antarctica’s Thwaites Glacier mixing underneath the ice, threatening the glacier’s collapse.”
The International Thwaites Glacier Collaboration tells us “New high resolution images of the seafloor in West Antarctica show past retreat of Thwaites Glacier. They reveal that at times in its past, retreat of the massive Thwaites Glacier was even quicker than it is today, heightening concerns for its future.”
No matter how scientists interpret the data, this is all very interesting. I still want to know what is causing the ocean to become the temperature of bath water (well, almost.)
I found Nature magazine carried in an Abstract, dated February 11, 1993, which reads in part:
It is widely understood that the collapse of the West Antarctic ice sheet (WAIS) would cause a global sea level rise of 6 m, yet there continues to be considerable debate about the detailed response of this ice sheet to climate change. Because its bed is grounded well below sea level, the stability of the WAIS may depend on geologically controlled conditions at the base which are independent of climate.
And now, I offer you the final and, hopefully, conclusive excerpt regarding the warming of the ocean and the melting of the Thwaite glacier. It is from the Abstract
published by Nature August 18, 2021, and titled “High geothermal heat flow beneath Thwaites Glacier in West Antarctica inferred from aeromagnetic data.”
Geothermal heat flow in the polar regions plays a crucial role in understanding ice-sheet dynamics and predictions of sea level rise. Here we analyse geophysical data to estimate geothermal heat flow in the Amundsen Sea Sector of West Antarctica. We show that the rapidly retreating Thwaites and Pope glaciers in particular are underlain by areas of largely elevated geothermal heat flow, which relates to the tectonic and magmatic history of the West Antarctic Rift System in this region. Our results imply that the behavior of this vulnerable sector of the West Antarctic Ice Sheet is strongly coupled to the dynamics of the underlying lithosphere.
Yea! I was right. Okay, I’ll admit this is just the beginning of learning about the cause of ocean warming. But it’s a good first step.