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Anthropogenic Climate Change is a Form of Secular Apocalypticism: 3

July 18, 2019 13 comments

In the previous part of this series, I wrote about how there is lots of paleontological evidence that Antarctica (as late as 2.6-2.3 million years ago) was much warmer than it is today. This becomes extremely relevant to any debate about anthropogenic climate change since its ardent believers keep harping about how greenhouse gases released by human activity will, directly and indirectly, cause the ice sheet at both poles to melt and causes sea level rises not seen in many millions of years. As readers have probably figured out by now, the biggest problem with this argument is that Antarctica was far less glaciated until the last two million years. To put it another way, that continent was much warmer over millions of years when the atmospheric CO2 was either equal to or less than current levels. And this occurred while the continents were at their current positions.

So let us talk about paleontological evidence for the most recent forests on that continent. But before that, have a look at first figure (below) to familiarize yourself with its major geographical features- as they appear today. As you can see, Antarctica looks like two continents smushed together and that is sorta correct. Based on surveys using ice-penetrating radar, the larger part aka East Antarctica looks like just another continent with plains, hills and mountain ranges. West Antarctica, on the other hand, is dominated by a striking series of parallel mountain ranges and an unusually wide continental shelf. Note that removing all that ice would cause some of the land currently below sea level to rebound due to isostatic rebound. Here is another link to what lies under that thick ice sheet. Antarctica is like a larger and more mountainous version of Australia.

The 2nd longest mountain range in Antarctica, which partially sticks above the ice, is known as the Trans antarctic mountains or TAM. FYI, the longest one in that continent is found in West Antarctica and is known as the Antarctandes Anyway, back to TAM. You might notice that parts of this range runs pretty close to the geographical south pole. One of the main passages through this range to the polar plateau beyond is a very long and large glacier known as the Beardmore Glacier. One of first famous and tragic attempts to reach the south pole used this route, and oddly enough, is relevant to this topic. The exposed fossil bed of interest aka Oliver Bluffs is located near this glacier. While the plant fossils at this site were first reported in the late 1980s, there is good evidence that Robert Scott of the ill-fated expedition in early 1910s might have discovered this site since he described finding fossilized leaves similar to northern beeches.

Anyway, as you can see in the third figure (below) this area is now very cold, icy and devoid of plant life. While a few coastal areas of Antarctica, especially north of 65 degrees South do have some vegetation- most of it is of the non-vascular type. To date, only two species of vascular plants (Deschampsia antarctica and Colobanthus quitensis) have been found on that continent and they look like stunted shrubs. Oliver Bluffs, on the other hand, is at 85 degrees South and less than 500 km from the south pole. So why did a site that is 20 degrees south to the most southerly parallel currently capable of supporting any vascular plant life host a forest with decent sized southern beech trees and an undergrowth of other plants. More importantly, how was this possible as late as 2-3 million years ago when atmospheric CO2 levels were lower than today?

The fourth figure (below) is a composite of some photographs taken at that site. You might notice that the quality of fossilization is pretty good and one of the layer containing them is sandwiched between two glacier-derived layers implying that that the region went through repeated rounds of glaciation and reforestation. And this brings us to the next question- where did all those seeds for regrowth of these trees come from? While it is not totally impossible that those seeds were dispersed by birds from other continents, the nearest place with such trees (New Zealand) is about 4,000 km away. In other words, it is far more likely that there were more local and permanent forests containing such trees on the Antarctic mainland. But this would mean that a significant part of Antarctica , especially north of 75-70 degrees South and near the ocean was not covered by an ice sheet. Moreover, even the inland ice sheets at that time must have been significantly thinner and smaller than today. So what was going on?

Here is one recent and accessible paper which goes into some detail about various methods used for reconstructing temperature conditions at the Oliver Bluffs site. As you can see, these plant fossils have been dated to the Pliocene (5.3-2.6 million years ago) for past thirty years. Also scientists have been talking about their implication on the climate of that region for almost that long. While some have tried to dispute the dating of these fossils, it is increasingly clear that they do indeed come from somewhere between 4 and 2.6 million years. For example, analysis of pliocene marine sediments from an offshore drill core dated to between 5 to 2.2 million years and over a thousand km from the site with those plant fossils has revealed the presence of fossil nothofagous pollen including from the species found at Oliver Bluffs.

To quickly summarize, there is evidence that many coastal regions of Antarctica were about 30 degrees Celsius warmer than today and resembled parts of Northern Canada, Inland Alaska and Northern Russia during the late Pliocene (2.6-2.3 million years ago). It is also likely that the inland icesheets during that era were significantly thinner and smaller than those present today. Let me remind you that this was during a time when atmospheric CO2 levels were identical or lower than those seen today. Are you beginning to see the problem with current propaganda driven narratives about “global warming” and “anthropocentric climate change”?

What do you think? Comments?

Anthropogenic Climate Change is a Form of Secular Apocalypticism: 2

July 14, 2019 5 comments

In the previous part of this series, I wrote that over the past 540 million years, there hasn’t been much correlation between atmospheric levels of CO2 and average global temperatures. Believers in the secular religion of anthropogenic global warming might attribute this to continents having different relative and absolute positions in the past due to plate tectonics. Therefore, I urge you to have a look at this YouTube clip of the reconstructed positions and movements of continents over that period. As you will notice pretty quickly, the relative and absolute positions of many continents does change a lot over that period. FYI- relative positions of these continents (more precisely their constituent cratons and shields) over that time-span has been deduced via a combination of techniques ranging from geology, paleontology, chemical and isotope analysis etc.

The fact that atmospheric levels of C02 ranging from 20x to 2-3x those seen today had little effect on average global temperature over such a long time-span and variety of continental arrangements, if anything, bolsters the argument about it being a relatively minor player in the larger scheme of things. Also note that most modern continental landmasses, except India and Australia and to some extent South America were near their current latitudes by 80 million years (at 5:10 in first clip) or about 15 million years before dinosaurs went extinct. Furthermore, the Eocene Thermal Maximum (at 5:38) occurred when most major continents were pretty close to their current latitude and longitude. Also, the most recent cycle of ice ages began about 6 million years ago (6:24-6:34) when all continents were, for practical purposes, at their present location.

Let us move to a related topic, namely for how long has the current ice-sheet covering Antarctica been around. As you will soon see, the answer is more surprising and complicated than you might have expected. So let us first talk about the position of that continent relative to the geographical south pole for the past 540 million years, as seen in second clip. Long story short, some part of the modern Antarctic continent has been within the southern polar circle (south of 66.5 degrees S) for the past 400 million years.. which is, geologically speaking, a pretty long time. More surprisingly, the geographical south pole has been within the land mass of Antarctica for at two extended periods within those 400 million years- from 0 to 120 million years ago and 260 to 350 million years ago. To put it another way, Antarctica has been the south polar continent (often along with Australia) for a bit longer than vertebrates first crawled on dry land.

So how was the climate in Antarctica during the past 400 million years? Well.. for a good portion of that period, it was what we would today classify as temperate, albeit with an interesting twist due to being loacted at extreme southern latitudes. It may have been warmer (subtropical?) during the period between 240-400 million years ago, but once again with that peculiar seasonality. The more peculiar and relevant part is that Antarctica has been pretty close to its current position for the past 80 million years and had a cool temperate climate for at least half that period. In other words, having long dark winters and long bright summers did not cause that continent to become a barren and frozen wasteland for many tens of millions of years.

The first evidence of some glaciation on that continent in the past 200 million years seems to have occurred around 40-35 million year ago. So what caused this cooling? Well.. the current explanation is that it was due to the Antarctic Circumpolar Current (see figure below) which started up after both South America and Australia had separated from Antarctica to a point where such a current could form. The popular conventional view is that ACC created a cold barrier around Antarctica about 35 million years ago and it hasn’t ever gotten warmer since then. Indeed, official information sources on the internet try to endlessly repeat this lie. To be clear, nobody is denying that the ACC has been there in its current form for the past two million years. But the evidence for climate on Antarctica for past 35 million years is far more complicated than many “credentialed experts” are willing to admit in public for reasons that will soon be obvious.

As many of you might have guessed, our knowledge about the geology and paleontology of Antarctica is much sparser than for other continents. Nevertheless, a number of surveys for plant and animal fossils have revealed evidence which simply does not fit with the popular version of Antarctica being a frigid wasteland for the past 35 million years. For example, there is decent evidence that parts of Antarctica had extensive tundra like vegetation throughout the Oligocene to the mid Miocene (24-14 million years ago). Even conifers existed on that continent as late as 15 million years ago. But the most striking evidence concerns the last forests in Antarctica, which existed as late as 2.3-2.6 million years ago.

To be clear, the last forests on that continent were restricted to certain regions and their tree biome was largely made up some of most cold-resistant species. Having said that, we can use the types of tree and micro fossils found at those sites to estimate contemporary climatic conditions. A cold-resistant genus of trees known as Nothofagus aka southern beeches are well represented in those fossils. As luck would have it, living members of that genus can be found in the southern Andes, parts of Australia and New Zealand. To make another long story short, the region of Antarctica where those fossils were found would have to be about 30 degrees Celsius warmer than it is today for even the most cold-tolerant species in that genus to exist. Also, there is a lower temperature limit for vascular plants.

In the next part of this series, I will go into some detail about the fossil and chemical evidence for why we think that those southern beech forest in Antarctica were so recent. As you will see, there are other independent lines of evidence to support the contention that Antarctica looked and felt a lot like certain parts of Northern Canada and Siberia as late as 2.3-2.6 million years ago. But such streams of evidence also create a huge problem for the popular model of Antarctica as an icebox in the past 35 million years. I mean.. why did Antarctica go through pretty large and incomplete cycles of partial glaciation and deglaciation within the past 40 million years, when it was close to its current location, isolated from other continents and levels of atmospheric CO2 were in current range or lower. Also, why did the continent become a frozen icebox only in past 2.3 million years? As you will see in next part, reality has a way of derailing theoretical models.

What do you think? Comments?