One might think that an interested reader would click one or more of the links he provided to see what his underlying evidence amounted to.
Ah I've long given up at being surprised when people persist in arguing from a position of complete ignorance. But it does still rub me up the wrong way
WARNING: this is a
long post, but there are a great many points to cover in countering the wilder claims made by Kamis in his “Climate Change Dispatch” article. The diligent reader will be able to find a lot of additional information with the help of Google and a good textbook or two.
Before we start, it is important to consider where the article posted by Ed was published. Climate Change Dispatch (CCD) one of the main climate change denier/skeptic websites. So when Kamis writes
“Climate scientists […] should broaden their research and analyzation process […]. It’s time for all of us to help these well-intentioned scientists achieve this goal.” the implications are clear: those ‘mainstream’ climate researchers have 1) not yet considered subglacial volcanic activity, 2) therefore their interpretation of what is going on at the West Antarctic Ice Sheet (WAIS) is incorrect, and 3) thus they are wrong about anthropogenic global warming (AGW) in general. His already biased CCD audience will nod and agree, the vast majority ‘blinded by science’. A few might click the links to the original papers cited, but those are highly technical and difficult to understand for the layman. Thus, the duty for scientists to ‘simplify’ the information contained within those papers and convey the message(s) to their audience in a correct and dispassionate manner. So let’s examine whether Kamis has done so.
First, a small personal note and a bit of an introduction to the topic at hand.
As a young lad I was always fascinated by distant lands, exotic cultures, wildlife and landscapes. One particular image that stuck in my mind was a photograph (taken by a colleague-to-be as it turned out) of a 4x4 driving on an empty road in front of an imposing, ice-shrouded mountain range. Something like this (
https://akamina.co/products/icelandic-road-2) but with a car in it. The picture was of the imposing Öræfajökull volcano in southern Iceland. It inspired me to take up Earth Science in university, and later on to spend a year in Reykjavík studying the local geology. In addition to punching well above its weight in international football, Miss World winners and horrible food, few places can compete with Iceland when it comes to the combination of volcanoes and glaciers. Unsurprising therefore that the ways these two interact were a significant topic in my degree, and Iceland hosts some of the world’s experts on subglacial volcanism.
When thinking about ‘volcanism’, it is important to keep in mind that this is not simply the eruption of lava and big clouds of smoke that wreak havoc on international air traffic. Volcanoes occur along weak spots in the Earth’s crust, either where tectonic plates drift apart (rift zones) or collide (subduction zones), or over particularly hot ‘plumes’ of mantle material (hot spots). Examples are the Mid-Atlantic Ridge and East African Rift Valley (both rift zones), the Andes (subduction zone) and Hawaii (hot spot). Iceland is a bit special because it’s a hot spot
on top of a rift zone. The vast majority of volcanic activity occurs underground, but on the surface it leads to two things: geothermal heat and eruptions. Geothermal heat is (more or less) continuous and does what it says on the tin: warm up the surface. Not by an incredible amount, millions of people live in areas of elevated geothermal heat flow, but significant nonetheless and it’s on 24/7. For comparison, geothermal heat flow is only 0.03% of solar irradiance absorbed by the Earth. Volcanic eruptions on the other hand produce vast amounts of surface heat, but only episodically and for a short amount of time (especially geologically speaking). It’s true that some eruptions go on for years and years, but the vast majority don’t. In addition to producing heat and lava, volcanic eruptions also introduce gasses and dust into the atmosphere that can take years to settle down/dissipate (and may lead to temporary global cooling events, e.g. the late 18th century Laki eruption). Some people have argued that there has been a recent increase in volcanic activity, and even that this is what’s driving global warming. However, those claims are not substantiated by the data as eruption levels have remained ‘constant’ for the past 200 years at least (see discussion here:
https://www.metabunk.org/debunked-significant-increase-in-volcano-eruptions.t6225/).
So, on to glaciers and ice caps/sheets. It is important to keep in mind that these are
hydro-meteorological surface features that form wherever accumulation of snow exceeds melting/ablation for a good number of years (enough for the snow to compact and form perennial ice). Typically this is in areas that are cold (high latitude and/or altitude) and receive a lot of precipitation. Thus,
the primary driver for glacier formation and size is climate, specifically the interaction between local climatological conditions and topography, although a few other factors come into play (see below). As an example, Iceland’s relatively low mountains in the south and west have glaciers (due to high precipitation), while similar mountains in the north and east do not (too dry). Note that our weather systems generally move west to east due to the Earth’s rotation, so mountain ranges facing oceans to their west are particularly prone to high precipitation and glacier formation (e.g. Alaska, British Columbia, Patagonia, Norway, Antarctic Peninsula). Glaciers gradually slide downhill, with most of the mass accumulation happening high up, and most of the melt happening lower down. This mass balance is highly sensitive to changes in climatological conditions, and a sustained change in weather pattern over many years will induce significant growth or shrinkage. Again, note that this includes changes in both temperature and precipitation (and in many cases wind). It’s not as simple as saying ‘it got warmer/colder’, therefore the glacier got smaller/bigger’. The rate at which a glacier moves downhill is influenced by its mass balance, the bedrock topography (terrain roughness) and something called basal melt. Basal melt is mostly generated by friction, but can be increased by geothermal heat (more on that below), which creates river systems and sometimes lakes at the glacier bed, literally lubricating its base. However, many high latitude glaciers (Greenland, Antarctica) have very little basal melt, meaning the glacier is frozen to the bedrock and moves only very slowly. Finally, there are marine-based glaciers which terminate directly in the sea. These are particularly sensitive to changes in the marine environment (water temperature, sea level) as this can create a ‘pull’ factor because the end of the glacier literally floats at the sea surface.
How do the two combine? Well, Earth scientists have been studying the effects of subglacial volcanism (volcano under enough ice) on the behaviour of both volcanoes and glaciers for decades. They’ve even looked for them on Mars (
http://www.spacedaily.com/news/mars-volcano-01b.html). And the dynamics are quite well understood, with many recent observations coming from Iceland. So is geothermal heat on its own enough to affect or prevent formation of a glacier? Somewhat, but judging by the number of glaciers
on top of active volcanoes the answer is a firm no, not if the annual snow accumulation rate is sufficient. And seen as geothermal heat flux is insufficient to prevent glaciers from forming even in places like Kilimanjaro, it certainly isn’t enough to completely melt through ice caps hundreds or thousands of meters thick. Elevated levels of geothermal heat do increase the basal melt which makes the glacier slide downhill easier, but remember that the final ‘speed’ depends on basal topography and ice mass balance as well. Volcanic eruptions are easily capable of blasting a hole through a thick layer of ice; for example, in 2010 Eyjafjallajökull melted through a few hundred metres of ice (generating that annoying ash cloud) (
https://volcano.si.edu/volcano.cfm?vn=372020). However, that ice cap is now recovering rapidly despite high geothermal heat flow in the caldera. Eruptions may be powerful, but they are infrequent and do not affect the situation
in the long term. For that the hydro-meteorological conditions which are the driving force behind glaciation need to shift significantly.
After that long introduction, let’s have a look at the Kamis article and the claims made therein:
Climate scientists (including those working on Antarctic ice sheet dynamics)
have not considered geological forces, like subglacial volcanoes
This is clear nonsense. I was taught about subglacial volcanism at uni 20 years ago. The processes involved are well understood, if not always well constrained on a case-by-case basis (more on that below). There is a large body of scientific literature spanning decades of research, some of which is cited in the Loose et al. (2018) paper kindly attached by Ed. What about the rift system beneath the West Antarctic Ice Sheet? Surely that’s ‘new information’? Not really. This study from 2017 gives an in-depth overview of the WAIS and the underlying West Antarctic Rift System (
http://sp.lyellcollection.org/content/early/2017/05/26/SP461.7), which has been known to exist for decades.
Either Kamis truly believes his own statement (in which case he is woefully uninformed), or he made it in order to increase his own apparent authority for the readers of CCD.
The conclusions of the [Loose et al. 2018] research study […] cites bedrock geothermal heat flow as the root cause of Pine Island Glacier melting
Except…the paper doesn’t (surely you spotted that Ed?). The conclusions of the paper are entirely in line with what I discussed above; and they finish with the following:
“The magnitude and the variations in the rate of volcanic heat […] may impact the future dynamics of the Pine Island Glacier, during the contemporary period of climate-driven glacial retreat.”
In other words, either Kamis hasn’t read the entire paper, not understood it, or is lying for the benefit of his climate-sceptic audience. Take your pick.
This research study entitled “Bedrock in West Antarctica rising at a surprisingly rapid rate” shows that the very well-defined Marie Byrd bedrock mantle plume “hotspot” (MB plume) region is rapidly rising and forming an extensive high elevation dome.
Kamis refers here to a press release from the Jet Propulsion Laboratory about one of its own studies. Seroussi et al. 2017 (
https://agupubs.onlinelibrary.wiley.com/doi/epdf/10.1002/2017JB014423) parameterized geothermal heat flux above the MBL mantle plume (which incidentally has been in evidence since the Pliocene) with the following conclusion:
“The experiments show that mantle plumes have an important local impact on the ice sheet, with basal melting rates reaching several centimeters per year directly above the hotspot”.
Significant yes, and with important implications for overall WAIS stability. But several cm losses are easily within the range of glacial accretion rates for the Western Antarctic
under current hydro-meteorological conditions – should those change then the additional basal melt may contribute to instability of the ice sheet, especially given that contains many marine-based glacier systems.
The Technical University of Demark (TUD) spearheaded the study which concluded that rapid elevation rise of the MB plume region is the result of post-glacial rebound. […]There are several problems with invoking post-glacial rebound as the cause of the MB plume region bedrock uplift [because 41 mm/year is] abnormally high when compared to normal post-glacial rebound rates [of] 25 millimeters per year
Kamis again cites a press release, but forgot to include the actual reference. It took a second to find it, because the work was not actually done at the TUD; the postdoc who did the work
while at Ohio State University has since moved to the TUD (whoops, sloppy). Anyway the paper is in Science (
http://science.sciencemag.org/content/360/6395/1335) and suggests the rapid uplift may actually help stabilize the WAIS in future, although this idea is disputed by others. What’s puzzling is Kamis’ assertion that 41 mm/year is too high for post-glacial geostatic rebound over mantle plumes – for example in Iceland rates of up to 92 mm/year have been calculated (
http://jgs.lyellcollection.org/content/167/2/417). Thus, his next assertion is incorrect:
It is here likely that the rapid elevation rise rate of the MB plume region is caused by the uplifting action of geological forces and one has to wonder what other uplifting forces he has in mind? Presumably the mantle plume itself,
but that was already included in the study he refers to, plus fully in line with known rates
over mantle plumes.
Additional information concerning the geologically active Marie Byrd bedrock mantle plume “hotspot” and the giant deep-earth fault that fuels this plume…
Kamis demonstrates that, despite his undergraduate degree in geology, he has no clue what mantle plumes are. Hint: they are not fueled by giant deep-earth faults…
This study, entitled “New study suggests surprising wrinkle in the history of West Antarctic Ice Sheet”, proves that the WAIS significantly melted and retreated 10,000 years ago, then quickly recovered to its full extent. […] This information strongly indicates that ancient ice melting of the WAIS is almost certainly related to underlying bedrock geothermal heat flow from geographically specific geological features and not worldwide atmospheric global warming.
Another press release, not a study, and when you actually read it is says the following:
“The warming after the last Ice Age made the ice masses of West Antarctica dwindle rather rapidly. […] It retreated inland by more than 1,000 kilometers in a period of 1,000 years in this region—on geological time-scales, this is really high-speed. But now we detected that this process at some point got partially reversed. Instead of total collapse, the ice-sheet grew again by up to 400 kilometers. This is an amazing self-induced stabilization.
However, it took a whopping 10,000 years, up until now. Given the speed of current climate-change from burning fossil fuels, the mechanism we detected unfortunately does not work fast enough to save today's ice sheets from melting and causing seas to rise.” (
https://phys.org/news/2018-06-wrinkle-history-west-antarctic-ice.html)
So not at all a rapid reversal as Kamis claims…misreading again or twisting the facts?
Combining the data and conclusions of three brand new research studies with very telling older research studies and previous CCD articles, it becomes very clear that melting of West Antarctica’s Ice Sheet is the result of bedrock geothermal heat flow, not atmospheric global warming.
Leaving aside the scientific ‘credibility’ of previous Climate Change Dispatch articles, this is 100% Kamis’ own interpretation. All his cited sources disagree with him (but who in his audience is going to check?), and his reasoning flies in the face of geological knowledge (and common sense). Instead, I recommend the review article by Van Wijk de Vries et al (2017), which I cited earlier and which discusses the WARS and its impact on the long-term stability of the WAIS in detail:
http://sp.lyellcollection.org/content/early/2017/05/26/SP461.7. As the authors conclude:
“Geological evidence points to the likelihood that the WAIS experienced extensive retreat during Quaternary glacial minima and concurrently contributed several metres to global sea-level rise. Currently, the WAIS may be undergoing another such wholesale retreat, as ice in the Pacific facing sector has consistently been retreating from the time of the earliest aerial and satellite observations.
We do not consider it likely that volcanism has played a significant role in triggering the current retreat, for which there is compelling evidence that the forcing has initiated from the margins, but we do propose that subglacial volcanism has the potential to influence future rates of retreat by (1) producing enhanced basal melting that could impact upon basal ice motion and (2) providing edifices that may act to pin retreat.”
Hopefully my long introduction has provided some background for this conclusion, which makes sense from a scientific point of view.
Finally, I wanted to link to this exhaustive review of the glacial history of Antarctica:
https://www.uni-trier.de/fileadmin/fb6/prof/GEO/Kilian/Ingolfsson_SUMMARY_Antarctica.pdf
Thanks for bearing with me, I hope the post was informative, and I urge everyone following the climate ‘debate’ to always fact check their sources.
Cheers,
Joost
P.S. happy to provide pdf’s or additional info as always!