this video is brought to you by Squarespace in 2006 researchers first detected a strange peak in the amount of methane in Earth's atmosphere a greenhouse gas more powerful than carbon dioxide while the scientific Community rushed to explain the sudden rise they found to their surprise that for once at least it didn't match any relative increase in human fossil fuel use it looked as if overnight a big new source of methane had simply turned on something happening on a global scale but no one could determine what was actually causing it these methane spikes happen every 100,000 years or so and are usually an indication of an Ice Age termination event a rapid warming at the end of an ice age that within just a couple of decades transitions the planet from largely ice covered to The Climate that we experience today but the last one only happened 12,000 years ago at the end of the last glacial maximum so why are we seeing another rise in methane so soon and what is is causing it and 16 years later as the peak continues to grow year on year are we on track for a major climate reversal this is a topic that I find absolutely fascinating it's rare we find such a predominant Smoking Gun of something happening on a global scale that we fundamentally don't understand that also isn't the result of our direct impact on the planet to answer the question of what is actually going on here we need to understand some of the history of the planet and its climate currently we're in the quaternary period spanning from about 2.58 million years ago to the present day the quaternary period has broken into two different epochs the first is the place theine Epoch from about 2 and a half million years ago to 11,700 years ago and it was known for its cyclical ice ages where during glaciation periods vast ice sheets would expand to cover much of North America northern Europe and Asia then after several tens of thousands thousand of years they would Retreat over just a few thousand years to a period of warmer Global Climate the pine also saw significant evolutionary developments and migrations for humans for instance Homo erectus emerged in the early Pine and the atomically analogous modern Homo Sapien appeared later in the epoch eventually colonizing most of the planet the pine also witness the megap foral extinctions where many large animals like Willy mammoths mastadons saber-tooth cats eventually went extinct this was partly due to human hunting pressures but it was thought mostly to be driven by the significant climate shifts that could have disrupted habitats and food sources in many of the megal foral species as the planet transitioned into its second Epoch the hollene we've had one yes what about second Epoch from about 12,000 years ago to the present day marks the most recent period where the glaciers retreated and the planet has seen relatively stable and warm climate conditions here's where the terminology gets I think a little bit confusing we are still technically in an ice age just an ice age where the glaciers don't cover as much of the planet as they can do we call this period an interglacial period 50 million years ago the planet was too hot for any ice to form at the poles so relative to that the Earth is definitely still in an ice age this most recent Hollen Epoch is significant for human history as the stable and comparatively warm climate allowed for the development of Agriculture and consequently the growth of large human settlements and complex societies culminating obviously in the creation of social media the transition that brought us from the holos scene and from all glacial to interglacial periods are called Ice Age termination events again we're still in the Ice Age yes it's confusing these termination events are typically made up of three distinct phases though exactly the demarcations between each phase kind of vary depending on what researcher you're actually talking to the first phase is called the deglacial onset its slow but steady increase in global temperatures marking the beginning of the end for the glacial period it usually lasts several tens of thousands of years this is often driven by changes to Earth's orbit called malanovic Cycles these predominantly relate to how the Earth is angled or orbiting around the Sun starting with eccentricity it describes the Earth's orbit around the Sun and measures how much the orbital path deviates from A Perfect Circle this can vary from zero it's a perfect circle to around 0.067 it's more of an oval or an ellipse currently the eccentricity is around 0.017 so we are pretty circular in our orbital nature when the Earth's orbit is more elliptical though the difference in solar energy that the Earth receives called insulation which is a word I have to look up every single time I need it between the closest approach and the most distant approach can vary tremendously this effect has a periodicity of roughly 100,000 years and over the past 800,000 years for which we've got data from Ice records termination events have been pretty well aligned with this cycle leading to Major glacial to interglacial shifts approximately 100,000 years apart but actually we don't think that this particular factor is the predominant milankovich driver of a termination event as the Earth rotates around the Sun it is tilted at an angle of 23.5° but over time this oscillates between approximately 22.1 and about 24.5 in a period of 41,000 years from minimum to maximum or about 82,000 years for a full oscillation from 21° all the way up and then all the way back down again when the Tilt is greater what this does is expose a larger polar region and means that it receives more solar radiation during the summer which can ultimately lead to more rapid melting of the ice sheets this in turn can have various feedback effects on the global climate looking at these events over the last 800,000 years you can see there's a huge amount of correlation between when they occur and when we are triggered into an Ice Age termination event today the axial tilt is decreasing from its maximum value and is moving towards the lower end of the range which should in theory be reducing the amount of melting effects on the ice caps the final effect I want to talk about is procession the wobble of the Earth's axis and affects the timing of the seasons relative to the position of Earth's orbit around the sun this possession cycle operates on time scales of approximately 19,000 to 23,000 years and we again see pretty regular alignment between these occurrences and termination events it obviously isn't perfect though it seems to be a combination of all these factors working together that actually drive a termination event to start these three malanovic factors drive a feedback loop which further propagates warming of the planet as the ice begins to melt darker Ocean or land surfaces are exposed these darker surfaces are better absorbers of sunlight which leads to further warming and more melting as the process continues the Earth enters a rapid warming period called full deglaciation with significant further ice melt and a corresponding rise in sea levels over a very short period usually over a matter of just decades this process is driven by the Rapid Release of greenhouse gases like CO2 and methane which were previously dissolved in cold oceans or in the Now Melting permafrost ice layers the release of these gases drives further warming accelerating the process and often driving reorganization and strengthening ocean currents which serve to distribute heat more evenly around the planet it's only after this second rapid heating phase that global temperatures begin to stabilize marking the onset of an interglacial period which is the period that we are in now these ice sheets will also stabilize and start to reduce reduce their size and sea levels will broadly come into some level of equilibrium while the system is still influenced by continuing effects of increased greenhouse gases milanovich Cycles negative feedback loops begin to play a more substantial role for instance as temperatures increase the growth of vegetation in previously ice covered areas acts as a carbon sink absorbing CO2 out of the atmosphere over a longer time scale weathering processes on land can then start to draw down atmospheric CO2 and lock it away in sediments and deposits while it also equilibrates with the now warmer oceans all of which serve to stabilize CO2 and temperature levels in the atmosphere this is the phase we're in now the hallene the interglacial period so why as of 2006 have we started to see this huge methane increase that we would only typically usually see in deglaciation phases of an Ice Age termination event it has been just 12,000 years since the last one not the usual 100,000 years that we usually see between the two what is going on but first I have to thank today's sponsor Squarespace Squarespace is the reason why I am where I 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down predominantly by hydroxy radicals to form CO2 and water while there is a much shorter lifetime for methane by comparison to something like CO2 it has a much higher warming potential for a couple of reasons methane's bonds and its structure are very effective at absorbing and emitting infrared radiation heat specifically at about 3.5 and 8 microns wavelength that 3.5 and 8 Micron band is also in an atmospheric window that usually can make its way freely out to space whereas CO2 absorbs around the 4 Micron and 15 Micron waveband which the atmosphere already absorbs effectively this makes methane's contribution to the greenhouse effect much more pronounced in the past few years we've become significantly better at detecting where methane is actually coming from both from the ground and from space as in measuring it from satellites not leaks from space there are a few ways of doing this passively and active approaches but one that I want to talk about that I think is particularly interesting is by firing a laser at the ground if you pick a wavelength of laser that's either 3.5 or 8 Micron in the infrared the earth looks a bit like a mirror and actually a lot of this light bounces off of the ground and some small fraction of it will make its way back up into the sky to your satellite by sweeping the laser over the ground if you suddenly see much less laser light coming back to you you know that it must have been absorbed and most likely it was absorbed by methane because nothing else in that band really absorbs those wavelengths this can help you create a map of methane levels around the planet in one search for methane that I saw teams from NASA's jet propulsion laboratory detected a plume of methane at least 3 miles long in the sky above an Iranian landfill this new found super emitter is pumping out about 18,700 lb or 8,500 kg of methane into the air every single hour that's a lot but interestingly it pales in comparison to a cluster of 12 super spotted in Turkmenistan all of them associated with oil and gas infrastructure and some of those plumes are up to 20 M long and together they're adding about 111,000 lb or 50,000 kg of methane to Earth's atmosphere every hour but these are reasonably recent events the most recent findings published in global biog geochemical Cycles which is a mouthful points to methane emissions increased from tropical and Wetland regions as increased temperatures and CO2 levels have driven faster growth this has meant that when trees and plants grow and then die and start to decompose it drives a higher rate of methane release we've touched on this already but also permafrost regions store vast amounts of carbon estimated to be about twice as much carbon as there currently exists in the atmosphere but they also contain trapped organic material as the permafrost Thor the organic material within it begins to decompose also releasing methane and fur further CO2 similarly while many modern landfills have methane capture systems not all of that methane is captured and some is released into the atmosphere the methane sensing technology I described previously is actually being deployed to both oil and gas infrastructure as well as landfills to help better map leaks and collect methane emerging from the ground and I would like to say that this is because we care about the environment and the climate but actually I think the stronger motivator is that if you can stop leaks you save money or if you can capture methane emerging from the ground you can pump it into a gas electric plant and burn it to produce electricity then sell that electricity to the grid to make money turning a literal pile of hot garbage into cash and yes this also generates CO2 burning methane but that's the lesser of two greenhouse gases to emit so what does all this actually mean for us although Agriculture and waste sources have increased between 2006 and 2022 to account for about half of the methane increase that we see the other half of recent growth in methane emissions is believed to be driven by natural biogenic processes especially the Wetland feedback loop and although the increase in global biogenic methane emissions is within the multicentury range of historic emissions meaning that it's not totally unusual that the planet could be producing this level of methane the speed and acceleration of this most recent trend is Extreme by all historical standards even during the post 1800s rise driven by fossil fuel use this component of methane's current change is likely outside anything Nature has ever done before at least in recent history all that to say it's not that we can't account for the methane increase we're getting increasingly sophisticated at understanding where it is exactly being emitted from it's more that we don't know what line this trend will follow and if it isn't directly us producing methane but nature itself it's potentially much harder to slow down or interfere or to stop this process capturing methane is really difficult even compared to capturing Co CO2 out of the air this is partly because methane is about 200 times less abundant in the atmosphere than CO2 there are some approaches out there that I've seen things like zeolites which are porous minerals that can convert methane to CO2 this approach and other ones like it though have largely gone underexplored because producing CO2 isn't a very useful byproduct at the moment but if it means that less potent greenhouse gases are emerging into the atmosphere some development in this area might actually be worthwhile the question remains though what is driving the change in our biomes that has moved them to this Mass methane output and will it slow down or will it get worse question two is what does this actually mean for our planet and there the honest answer is we don't really know the only thing we have to compare it to is past Ice Age termination events as a somewhat proxy of what might be happening here but this isn't a termination event driven by the usual mechanisms so we are totally off book in terms of what that actually means and what could be expected to happen here if we are in a termination like event given that we're in an interglacial period at the moment where the Glaciers are already receded could this knock us out of an Ice Age entirely at the moment like I said we really don't know in the words of the researchers in the most recent study it remains possible that methane's current growth is within the range of holine variability but it is also possible that this shift May indicate a large scale reorganization of the natur natural climate and biosphere is already well underway has merely a single pandemic or only a handful of financial crashes left you wanting more termination like events in your life I just did a video on NASA's work to deflect City destroying asteroids you can check it out here if you like this sort of content please do consider subscribing or if you 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