Published on the Doomstead Diner on September 27, 2015
Discuss this article at the Environment Table inside the Diner
Besides the ongoing collapse of the monetary system which fill the Newz headlines every day with a plethora of stories of bankrupt countries and mass layoffs, ever more people on Food Stamps and living out of their cars even if they have a full time job, probably the hottest topic in the collapse blogosphere is the question of Near Term Human Extinction. I've covered it in rants and I've done surveys to see what the readers think on this topic also, but it's the collapse gift that keeps on giving.
The most well known person throuh the collapse blogosphere hawking this concept is Guy McPherson who runs the blog Nature Bats Last, but by no means is he the only one these days. In his Encyclical, even the POPE insinuated this as a possibility in his Encyclical on Climate.
Before beginning here on debunking this idea, let me state for the record that NTHE is possible, and the longer you go out on the timeline the more possible it becomes. Go out far enough on the timeline, it's inevitable and always has been. As the tagline goes on Zero Hedge, "On a long enough timeline, the survival of everyone drops to Zero". The issue is about the likelihood this can occur on short timelines. In Guy's case, he has the timeline down to as soon as 2030 now. That means every last Homo Sap on the planet is DEAD in 15 years.
For our purposes in this examination though, we'll consider "Near Term" to be anything under a Century.
The second caveat to this examination is that it is looking strictly at the Climate Change problem, not at the possibility we are on a collision course with Planet X or that the numbskulls with their Fingers on the Nuke Buttons will push them and set off Global Thermonuclear War. Either of those as well as a few other scenarious could vastly accelerate the extinction of Homo Sap.
The question we are looking at here is:
Will a rise in Average Global Temperature (AGT) by 4C exterminate all Homo Saps inside the Next Century due to loss of Habitat and die off of many species we currently depend on?
Let's begin with what the current Average Global Temperature (AGT) actually IS at the moment.
Climatologists prefer to combine short-term weather records into long-term periods (typically 30 years) when they analyze climate, including global averages. Between 1961 and 1990, the annual average temperature for the globe was around 57.2°F (14.0°C), according to the World Meteorological Organization.
Now, according to the NOAA, as of August 2015, the current Average Global Temperature is 1.14C over the 20th Century Average.
The average global land surface temperature for August 2015 was 1.14°C (2.05°F) above the 20th century average
So let us be generous on the warming side and say the current AGT is up to 16 C now. Let us warm this up further by another 4C over the next 15 years to 20 C.
Now, Guy's hypothesis states that no Homo Saps have ever been alive when the AGT was that warm, and that is true. However, can you draw the conclusion from that it is IMPOSSIBLE for Homo Sap to survive at such an AGT? Other mammals (our ancestors) survived an even warmer time period, the Paleocene-Eocene Thermal Maximum (PETM) when the AGT went up to about 25 C or so. If other mammals could do it back then, why in principle can we not do it again this time?
The Paleocene–Eocene Thermal Maximum (PETM), alternatively "Eocene thermal maximum 1" (ETM1), and formerly known as the "Initial Eocene" or "Late Paleocene Thermal Maximum" refers to a climate event that began at the temporal boundary between the Paleocene and Eocene epochs. The absolute age and duration of the event remain uncertain, but are thought to be close to 55.8 million years ago and about 170,000 years of duration The PETM has become a focal point of considerable geoscience research because it probably provides our best past analog by which to understand impacts of global warming and massive carbon input to the ocean and atmosphere, including ocean acidification.
The onset of the PETM has been linked to an initial 5 °C temperature rise and extreme changes in Earth’s carbon cycle. The PETM is marked by a prominent negative excursion in carbon stable isotope (δ13C) records from around the globe; more specifically, there was a large decrease in 13C/12C ratio of marine and terrestrial carbonates and organic carbon.
Numerous other changes can be observed in stratigraphic sections containing the PETM. Fossil records for many organisms show major turnovers. For example, in the marine realm, a mass extinction of benthic foraminifera, a global expansion of subtropical dinoflagellates, and an appearance of excursion, planktic foraminifera and calcareous nanofossils all occurred during the beginning stages of PETM. On land, there was a sudden appearance of modern mammal orders (including primates) in Europe and North America. Sediment deposition changed significantly at many outcrops and in many drill cores spanning this time interval.
Although it is now widely accepted that the PETM represents a “case study” for global warming and massive carbon input to Earth’s surface, the cause, details and overall significance of the event remain perplexing.
Guy's case is that Habitat will be so destroyed globally by such a rise in AGT, that there simply will be NOWHERE Homo Sap can survive on the planet. Is that necessarily true?
Well, first off you have to remember this is an AVERAGE taken over the whole globe, it is not the average for a given region in any given time period. Right now, TODAY, many people live in neighborhoods which have yearly average temperatures quite a bit warmer than this. Lagos in Nigeria is one such place, but there are many in the equatorial regions of the Earth.
February is the hottest month in Lagos with an average temperature of 29°C (84°F) and the coldest is July at 25°C (77°F)
There are a LOT of people currently living in Lagos, like around 20M of them and that's just one Big Shity in Nigeria too! They don't all have HVAC either, in fact most of them live in slums with no electricity at all! So clearly, Homo Sap can survive at these temperatures.
Granted though, this is rather sweaty and uncomfortable weather overall, but if the AGT is 20C, does that mean every neighbohood is 20 C? Of course not, because the average temperature for any given location depends on its Latitude and its Altitude.
Starting with Altitude, you drop almost 2C for every 1000' in altitude you gain
Although the actual atmospheric lapse rate varies, under normal atmospheric conditions the average atmospheric lapse rate results in a temperature decrease of 6.4 °C/km (3.5 °F or 1.95 °C/1,000 ft) of altitude above ground level.
So, all you need to do in any given latitude is situate yourself 2000' above sea level and you have already knocked off 4 C tempeature rise on a global average.
The situation is similar with Latitude:
Temperature also decreases as latitude becomes more northward in the Northern Hemisphere and more southerly in the Southern Hemisphere. Latitude in this sense simply refers to a measurement of movement north or south across the surface of the earth. The general rule is that temperature changes three (3) degrees Fahrenheit for every 300 mile change in latitude at an elevation of sea level. If you are in the Northern Hemisphere, you can expect temperatures to be 3 degrees cooler 300 miles north, 6 degrees cooler 600 miles north, and so on, until you reach the North Pole. The same is true for the Southern Hemisphere, except that temperatures cool the further you travel from the equator toward the South Pole.
So, depending where you are in the Northern or Southern Hemisphere, you can knock off aroun 1.5C for every 300 Miles you move from your current location. Can you stand the heat where you currently live without HVAC? If you can, each time the AGT goes up by 1.5C, you just need to move another 300 miles north or south and you are back to where you started, and that is WITHOUT gaining altitude!
So clearly even with a projected 4 C rise in AGT, there are still going to be zones on the earth with still livable climate for Homo Sap. It is also by no means clear that we will get 4 C inside of 15 years either. So it has no good basis in scientific reasoning to suggest that Homo Sap will go extinct in such a short period of time, simply due to a 4 C rise in AGT.
Can Homo Sap experience an extreme Knockdown event in such a short time? That is much more possible, and perhaps even probable at this point. The number of neighborhoods that would have both good temperatures and enough water would be vastly reduced from what is available today. However, a Knockdown event is not an Extinction, and Homo Sap has experienced Knockdowns before and rebounded from them.
Although the cause is disputed, somewhere between 75-200K years ago Homo Sap DNA evidence shows that the population of Homo Sap around at the time experienced a severe bottleneck, which may have been quick or it may have gone on for some time, but the bottleneck is still there:
The Toba catastrophe theory as presented in the late 1990s to early 2000s suggested that a bottleneck of the human population occurred c. 70,000 years ago, proposing that the human population was reduced to perhaps 10,000-30,000 individuals when the Toba supervolcano in Indonesia erupted and triggered a major environmental change. The theory is based on geological evidence of sudden climate change and on coalescence evidence of some genes (including mitochondrial DNA, Y-chromosome and some nuclear genes) and the relatively low level of genetic variation in humans.
However, coalescence times for Y-chromosomal and mitochondrial DNA have been revised to well above 100,000 years since 2011. In addition, such coalescence would not, in itself, indicate a population bottleneck, because mitochondrial DNA and Y-chromosome DNA are only a small part of the entire genome, and are atypical in that they are inherited exclusively through the mother or through the father, respectively. Genetic material inherited exclusively from either father or mother can be traced back in time via either matrilineal or patrilineal ancestry.
In 2000, a Molecular Biology and Evolution paper suggested a transplanting model or a 'long bottleneck' to account for the limited genetic variation, rather than a catastrophic environmental change. This would be consistent with suggestions that in sub-Saharan Africa numbers could have dropped at times as low as 2,000, for perhaps as long as 100,000 years, before numbers began to expand again in the Late Stone Age.
So whether this bottleneck was fast or slow, whether the Toba Supervolcano caused it or not, whether the numbers dropped to 30,000, 10,000 or 2000, it's pretty clear the population of Homo Sap can rebound from a very small number to quite a large one, as today there are over 7B who reproduced up from that number.
So not a whole lot of people need to make it through this Zero Point to avoid an Extinction Level Event for Homo Sap.
So we have established now 2 things:
1- The climate in all places on earth is unlikely to become unfit for human habitation
2- The number of people who need to survive in order to avoid extinction is quite small
The next question to address is that of Positive Feedback Loops, which some folks suggest will send the planet into a Venusian style Global Cooking Event, with runaway heating that exceeds even the PETM. If that were to occur, most certainly Homo Sap and most other living things besides Extremophiles like the Tardigrades would not be able to make it through such an event. However, does the scientific record of Global Atmospheric Carbon content and Average Global Temperature suggest that is likely? No it does not.
As you can see, basically regardless of how much of the Global Carbon Reservoir gets dumped into the atmosphere for whatever reason, the AGT always plateaus out around 25C. So for all the Positive Feedback Loops that are out there, at 25C some Negative Feedback Loops must start to kick in. Unidentified as of yet what they are, but they must be there, otherwise we should have turned into Venus 170M years ago when global atmospheric CO2 was at around 2300 ppm. We got a lot of carbon to burn to get there in any event, and lots of clathrates have to melt too! That is not going to happen in 15 years.
The other issue here is what happens to the oceans and all the fishies during this period? Well, the Ocean is going to continue to acidify, and many current species are going to die off. Phytoplankton are of particular concern here, since they are in large part responsible for dropping molecular oxygen back into the atmosphere for the animals on the planet to breathe, including you and me. Can the atmosphere go Anoxic inside 15 years? No, not even if every last phytoplankton died could that occur, because the atmosphere is a very large sink. As more animals die off, less oxygen is consumed. So it takes some time to deplete the atmosphere of oxygen down to say 10% where it would be real difficult to survive. Although, well acclimated people such as the Sherpas can do OK at 8%. Obviously, as oxygen levels in the atmosphere decline, only people who can survive with such low concentrations would be selected for. In any event it takes some time for this to occur, a lot longer than 15 years. There are at least 3 currently living communities of people who can survive these low oxygen concentrations.
Prehistoric and contemporary human populations living at altitudes of at least 8,000 feet (2,500 meters) above sea level may provide unique insights into human evolution, reports an interdisciplinary group of scientists. Indigenous highlanders living in the Andean Altiplano in South America, in the Tibetan Plateau in Asia, and at the highest elevations of the Ethiopian Highlands in east Africa have evolved three distinctly different biological adaptations for surviving in the oxygen-thin air found at high altitude.
Above 25,000', fuhgettabboudit, not even Sherpas can last long up there. It's the DEATH ZONE. However, below 8000' or so, even with steady atmospheric oxygen concentrations depleting, it will take a good deal longer than 15 years for that one to occur.
The Death Zone on Everest
However, the likelihood that all the phytoplankton die off within 15 years itself is quite small. Remember, they all did not Buy their Ticket to the Great Beyond TM in the PETM, 5-10% of ocean species survived that event. Phytoplankton are single cell and they reproduce and adapt to changing environmental conditions rapidly. There has been a dieoff of around 50% of them over the last 40 years or so, but it is unlikely they ALL will die off inside even another 40 years, because this is asymptotic.
Land based ecosystems have their own set of parameters, and some will collapse quickly, others will persist for quite some time to come. As the population of Homo Sap dwindles, it will migrate to those zones that still have functional ecosystems. Then in addition, Homo Sap being Sentient can further augment what is available in the local ecosystem, through techniques like Hydroponics and Aquaculture.
This Greenhouse is on the North Slope of Alaska:
So you clearly can feed SOME number of people this way, it's a Non-Zero number, which by definition means you don't have Extinction. How big that number is remains open to question, but it is certainly more than 100,000, which is more than enough to provide genetic diversity for the species to recover over time.
Now, despite the fact the evidence above shows that Guy's 15 year timeline to Near Term Human Extinction is quite preposterous, does this mean we are not in BIG TROUBLE?
HELL NO! WE ARE IN THE DEEP DOO-DOO HERE!
We are going to have a LOT of DEAD PEOPLE!
What is important given this incontravertable fact of life is that the sooner we get started on addressing this problem realistically, the better we can make it possible for not only more people to survive this crash, but more of the rest of the ecosystem too!
For right now, making any changes on the gross geopolitical level is impossible. The Chinese are going to keep burning coal to keep their electric power plants running as long as they can. Happy Motorists in the FSoA will keep driving around willy nilly as long as they can too. The carbon will be burned, the climate will continue to become more inhospitable, for at least the next 40 years no matter what due to the lag time for many effects to show themselves.
However, individuals can begin the process of learning how to survive in a drastically changed environment, and communities can begin to form to handle it as well. It is up to each person to begin this process inside your own small sphere of influence. My small sphere is the Doomstead Diner , collapse.global & Sun4Living websites. That's my effort, that is all an old cripple can do.
If you have talent, knowledge and/or experience, you too can make a difference, and this is no time to be a QUITTER. Resigning yourself to an inevitable fate of EXTINCTION in the Near Term is QUITTING. Accepting this situation as HOPELESS is QUITTING.
This is a battle that can be fought, and it is a battle that can be WON! Not without a lot of pain and a lot of loss, to be sure, but giving up is not an option, unless you really WANT to die, or you want our whole species to die because you think we are so awful and bad to have around on the planet. If you want to LIVE, you look for means and methods to SURVIVE.
This battle has been waged before by the ancestors of Homo Sap in the PETM, and they won it.
DONE ONCE, IT CAN BE DONE AGAIN.