We are now in the Suicene

The Holocene is the geological epoch that started approximately 11,650 years ago. The demarcation point between the Holocene and the preceding Pleistocene is the end of the last Glacial Period, in line with variations in the Earth's orbit. 

Anthropocene

Instead of going down as would be in line with changes in the Earth's orbit, temperatures and greenhouse gas levels over the past few thousands of years have kept going up as a result of activities by people. In other words, changes in the Earth's orbit were no longer the dominant force causing changes in temperature and greenhouse gas levels, instead, human activities had become more dominant. 

Start of the Anthropocene

It makes sense to name an epoch after the dominant force shaping its climate. An earlier analysis concludes that, from the year 3480 BC, emissions by people have been higher than the amount it takes to negate the natural trend for the temperature to fall. From 3480 BC, forcing due to activities by people was stronger than the natural fall in temperature that would have eventuated in the absence of such activities. This makes the year 3480 BC most significant as a climate marker, and it makes sense to regard this both as the base for the temperature rise from pre-industrial and as the start of the Anthropocene. 

End of the Anthropocene

At the Paris Agreement, adopted in 2015, nations pledged to limit the temperature rise to well below 2°C above pre-industrial levels, with efforts taken to limit it to 1.5°C above pre-industrial levels. The image below illustrates that, despite these pledges, these thresholds may already have been crossed. 

[ from earlier post, click on images to enlarge ]

The earlier analysis concludes that the rise from pre-industrial to 2020 could be as much as 2.29°C, which would mean that the thresholds set at the Paris Agreement have already been crossed and the rise from pre-industrial may well exceed 3°C soon, in turn effectively making 3°C the (new) threshold that should not be crossed, the more so since humans will likely go extinct with a 3°C rise, as illustrated by the image below, from an analysis discussed in an earlier post.

Humans are now functionally extinct

1. The situation is dire in many respects, including poor conditions of sea ice, levels of greenhouse gases in the atmosphere, extreme weather causing droughts, flooding and storms, land suffering from deforestation, desertification, groundwater depletion and increased salinity, and oceans suffering from ocean heat, oxygen depletion, acidification, stratification, etc. These are the conditions that we're already in now. 
   
   
2. On top of that, the outlook over the next few years is grim. Circumstances are making the situation even more dire, such as the emerging El Niño, a high peak in sunspots, the Tonga eruption that added a huge amount of water vapor to the atmosphere. Climate models often average out such circumstances, but over the next few years the peaks just seem to be piling up, while the world keeps expanding fossil fuel use and associated infrastructure that increases the Urban Heat Island Effect.
   
   
3. As a result, feedbacks look set to kick in with ever greater ferocity, while developments such as crossing of tipping points could take place with the potential to drive humans (and many other species) into extinction wirhin years. The temperature on land on the Northern Hemisphere may rise so strongly that much traffic, transport and industrial activity could suddenly grind to a halt, resulting in a reduction in cooling aerosols that are now masking the full wrath of global heating. Temperatures could additionally rise due to an increase in warming aerosols and gases as a result of more biomass and waste burning and forest fires.
   
   
4. As a final straw breaking the camel's back, the world keeps appointing omnicidal maniacs who act in conflict with best-available scientific analysis including warnings that humans will likely go fully extinct with a 3°C rise.

The Suicine

As we keep appointing omnicidal maniacs who act in conflict with best-available scientific analysis, we are now facing a temperature rise that looks set to drive humans into extinction. Humans are now functionally extinct, and another name change is in order. Indeed, we are now in the Suicene. 

Conclusion

In conclusion, we have left the Anthropocene. We are now functionally extinct and we look set to drag most, if not all life on Earth into extinction with us, as we keep appointing omnicidal maniacs who act in conflict with best-available scientific analysis. We are now in the Suicene.

In the video below, Sandy discusses the situation. 

 

The climate change runaway chain reaction-like process

Amplifying feedbacks leading to accelerated planetary temperatures

by Andrew Glikson

“The paleoclimate record shouts to us that, far from being self-stabilizing, the Earth's climate
system is an ornery beast which overreacts even to small nudges” (Wally Broecker)

Many climate change models, including by the IPCC, appear to minimize or even neglect the amplifying feedbacks of global warming, which are pushing temperatures upward in a runaway chain reaction-like process, as projected by Wally Broecker and other:

• Lateral and vertical ice melt, including formation of water films on ice; 
• Reduced CO2 intake by the warming oceans due to warming. Currently the oceans absorb between 35-42 percent of all CO2 emitted into the atmosphere and around 90 percent of the excess heat from the rise in greenhouse gases;
• Warming, desiccation, deforestation and fires over land areas;
• Release of methane from permafrost and polar sediments;

These feedbacks drive a chain reaction of events, accelerating the warming, as follows:

1. Melting snow and ice expose dark rock surfaces, reducing the albedo of the polar terrains and sea ice in surrounding oceans, enhancing infrared absorption and heating.
2. Fires create charred low-albedo land surfaces.
3. An increase in evaporation raises atmospheric vapor levels, enhancing the greenhouse gas effect.
4. Whereas an increase in plant leaf area enhances photosynthesis and evapotranspiration, creating a cooling effect, the reduction in vegetation in darkened burnt areas works in the opposite direction, warming land surfaces.

Figure 1. The 2021 global climate trends (Hansen, 2021, by permission)

The current acceleration of global warming is reflected by the anomalous rise of temperatures, in particular during 2010-2020 (Hansen 2021, Figure 1 above). Consequently, extensive regions are burning, with 4 to 5 million fires per year counted between about 2004 and 2019. In 2021, global April temperatures are much less than in 2020, due to a moderately strong La Nina effects.

Figure 2. The Palaeocene-Eocene Thermal Maximum recorded by benthic plankton isotopic data from sites in the Antarctic, south Atlantic and Pacific (Zachos et al., 2003). The rapid decrease in oxygen isotope ratios is indicative of a large increase in atmospheric temperatures associated with a rise in greenhouse gases CO₂ and CH₄ signifies approximately +5°C warming.

A runaway climate chain reaction-like process triggered by release of methane is believed to have occurred during the Paleocene-Eocene thermal maximum (PETM), about 55 million years ago (Figures 2 above and 3A below).

Analogies between Anthropocene climate change and major geological climate events reveal the rate of current rise in greenhouse gas levels and temperatures as compared to major geological warming events is alarming. A commonly cited global warming event is the Paleocene-Eocene boundary thermal maximum (PETM) at 55 Ma-ago, reaching +5 degrees Celsius and over 800 ppm CO₂ within a few thousand years (Figures 2 above and 3A below).

Figure 3. (A) Simulated atmospheric CO₂ at and following the Palaeocene-Eocene boundary (after Zeebe et al., 2009);
(B) Global CO₂ and temperature during the last glacial termination (After Shakun et al., 2012) (LGM - Last Glacial Maximum; OD – Older dryas; BA - Bølling–Alerød; YD - Younger dryas). Glikson (2020).

The definitive measure of Anthropocene global warming, i.e. the rise in the atmospheric concentration of CO₂, to date by 49 percent since pre-industrial time (from 280 ppm to currently 419 ppm), is only rarely mentioned by the media or politicians. Nor are the levels of methane and nitrous oxide, which have risen by about 3-fold. To date potential attempts toward climate mitigation and adaptation have failed. There is a heavy price in communicating distressing projections, Cassandra-like, where climate scientists have been threatened, penalized or dismissed, including from major institutions. 

The triggering of a mass extinction event by the activity of organisms is not unique to the Anthropocene. The end Permian mass extinction, the greatest calamity for life in geologic history, is marked in marine carbonates by a negative δ¹³C shift attributed to oceanic anoxia and the emission of methane (CH₄) and hydrogen sulphide (H₂S) related to the activity of methanogenic algae (“purple” and “green” bacteria) (Ward, 2006; Kump, 2011). As a corollary anthropogenic climate change constitutes a geological/biological process where the originating species (Homo sapiens) has not to date discovered an effective method of controlling the calamitous processes it has triggered.

Andrew Glikson

A/Prof. Andrew Glikson

Earth and Paleo-climate scientist
The University of New South Wales,
Kensington NSW 2052 Australia

Books:
The Asteroid Impact Connection of Planetary Evolution
http://www.springer.com/gp/book/9789400763272
The Archaean: Geological and Geochemical Windows into the Early Earth
http://www.springer.com/gp/book/9783319079073
Climate, Fire and Human Evolution: The Deep Time Dimensions of the Anthropocene
http://www.springer.com/gp/book/9783319225111
The Plutocene: Blueprints for a Post-Anthropocene Greenhouse Earth
http://www.springer.com/gp/book/9783319572369
Evolution of the Atmosphere, Fire and the Anthropocene Climate Event Horizon
http://www.springer.com/gp/book/9789400773318
From Stars to Brains: Milestones in the Planetary Evolution of Life and Intelligence
https://www.springer.com/us/book/9783030106027
Asteroids Impacts, Crustal Evolution and Related Mineral Systems with Special Reference to Australia
http://www.springer.com/us/book/9783319745442
The Event Horizon: Homo Prometheus and the Climate Catastrophe
https://www.springer.com/gp/book/9783030547332

Links image top

• Seasonal origin of the thermal maxima at the Holocene and the last interglacial - by Samantha Bova et al. (2021)
https://www.nature.com/articles/s41586-020-03155-x

• Could temperatures keep rising? - by Sam Carana (2021)

https://arctic-news.blogspot.com/2021/06/could-temperatures-keep-rising.html

• Blueprints of future climate trends - by Andrew Glikson (2018)
https://arctic-news.blogspot.com/2019/09/blueprints-of-future-climate-trends.html

• Global warming preceded by increasing carbon dioxide concentrations during the last deglaciation - by Jeremy Shakun (2012)
https://www.nature.com/articles/nature10915

• The Last Great Global Warming - by Lee Kump (2011)
https://www.scientificamerican.com/article/the-last-great-global-warming

The Fatal Road To 4 Degrees Celsius

The fatal road to +4°Celsius

Extreme GHG and T°C rise rates exceed climate tipping thresholds

Andrew Glikson

Precis

Global CO₂ rise and warming rates have reached a large factor to an order of magnitude higher than those of the past geological and mass extinction events, with major implications for the shift in climate zones and the nature and speed of current extreme weather events. Given the abrupt change in state of the atmosphere-ocean-cryosphere-land system, accelerating since the mid-20ᵗʰ century, the terms climate change and global warming no longer reflect the nature of the climate extremes consequent on this shift. Further to NASA’s reported mean land-ocean temperature rise to +1.18°C for March 2020, relative to the 1951-1980 baseline, large parts of the continents, including Siberia, central Asia, Canada, parts of west Africa, eastern South America and Australia are warming toward mean temperatures of +2°C and higher. The rate exceeds that of the Last Glacial Termination (LGT) (21–8 kyr), the Paleocene-Eocene hyperthermal event (PETM) (55.9 Ma) and the Cretaceous-Tertiary boundary (K-T) (64.98 Ma) impact event. A principal question arises regarding the relationships between the warming rate and the nature and progression of the current migration climate zones toward the poles, including changes in the atmosphere and ocean current systems. Significant transient cooling pauses, or stadials, are projected as a consequence of the flow of cold ice melt water from Greenland and Antarctica into the oceans.

Figure 1. Global temperature distribution in March 2020, relative to a 1951-1980 baseline. NASA GISS.

The K-T impact and subsequent warming: According to Beerling et al. (2002) the CO₂ change triggered by the K-T impact event 65 Ma years ago involved a rise from about 400-500 ppm to 2300 ppm over 10.000 years from the impact (Fig. 2) at a rate of 0.18 ppm/year. This is less than the mean Anthropocene CO₂ rise rate of 0.415 ppm/year and an order of magnitude less than the 2 to 3 ppm/year rise rate in the 21ˢᵗ century. Likewise the Anthropocene temperature rise rate of ~ 0.0074°C/year is high by an order of magnitude as compared to the K-T impact event rate of~ 0.00075°C/year (Table 1) reported by Beerling et al. (2002).

Figure 2. Reconstructed atmospheric CO₂ variations during the Late Cretaceous–Early Tertiary derived from the SI
(Stomata index) of fossil leaf cuticles calibrated by using inverse regression and stomatal ratios. Beerling et al. (2002).

Beerling et al.’s (2002) estimate, based on fossil fern proxies, implies an initial injection of at least 6,400 GtCO₂  and possibly as high as 13,000 GtCO₂ into the atmosphere, significantly higher than values derived by Pope et al. (1997). This would increase climate forcing by +12 Wm⁻² and mean warming of ~7.5°C, which would have strongly stressed ecosystems already affected by cold temperatures and the blockage of sunlight during the impact winter and associated mass extinction at the KT boundary (O’Keefe et al. 1989).

The PETM hyperthermal event: The Palaeocene–Eocene Thermal Maximum, about 55.9 Ma, triggered the release of a large mass of light ¹³C-depleted carbon suggestive of an organic source, likely methane, has led to a global surface temperature rise of 5 – 9°C within a few thousand years (Table 1; Fig. 3). Deep-sea carbonate dissolution indices and stable carbon isotope composition were used to estimate the initial carbon pulse to a magnitude of 3,000 PgC or less. As a result, atmospheric carbon dioxide concentrations increased during the main event by up to 70% compared with pre-event levels, leading to a global surface temperatures rose by 5–9°C within a few thousand years.

Figure 3. Simulated atmospheric CO2 at and after the Palaeocene-Eocene boundary (after Zeebe et al. (2009).

The last glacial termination: Paleoclimate indices based on ice cores and isotopic evidence suggest temperature rise generally correlates with CO₂ during the Last Glacial Termination between 17.5 kyr to 10 kyr. Whereas the rise rates of CO₂ and temperature are broadly parallel the temperature somewhat lags behind CO₂ (Figure 2). Changes of CO₂ – 186 - 265 ppm and of temperature of T°C -3.3°C - +0.2°C (Fig. 4). A rise rate of ~0.010 ppm CO₂/year and of temperature ~0.00046°C/year are indicated (Table 1) (Shakun et al., 2012). Differences between temperature changes of the Northern Hemisphere and Southern Hemisphere correspond to variations in the strength of the Atlantic meridional overturning circulation.

Figure 4. Global CO₂ and temperature during the last glacial termination (After Shakun et al. 2012).
(LGM – Last Glacial Maximum; OD – Older Dryas; B-A - Bølling–Allerød; YD Younger Dryas).

Trajectories and rates of global CO₂ rise and warming

The rates at which atmospheric composition and climate changes occur constitute major control over the survival versus extinction of species. Based on paleo-proxy estimates of greenhouse gas levels and of mean temperatures, using oxygen and carbon isotopes, fossil plants, fossil organic matter, trace elements, the rate of CO₂ rise since ~1750 (Anthropocene) (CO₂ ᴀɴᴛʜ) exceeds that of the last glacial termination (CO₂ ʟɢᴛ) by an order of magnitude (CO₂ ᴀɴᴛʜ/CO₂ ʟɢᴛ = 41) and that of the Paleocene-Eocene Thermal Maximum (CO₂ ᴘᴇᴛᴍ) by a high factor (CO₂ ᴀɴᴛʜ/CO₂ ᴘᴇᴛᴍ ~ 3.8–6.9)(Table 1). The rise rate of mean global temperature exceeds that of the LGT and the PETM by a large factor to an order of magnitude (Table 1; Figs 5 and 6). It can be expected that such extreme rates of change will be manifest in real time by observed shifts in state of global and regional climates and the intensity and frequency of extreme weather events, including the following observations:

• A shift in climate zones (Fig. 7) including expansion of the tropics and migration of moderate mediterranean-type climate zones toward the poles , estimated at a rate of 56-111 km per decade (Thurton 2017), signifying a fundamental shift in state of the Earth’s climate regime.
• A high rate of ice melt and development of cool ocean pools south of Greenland and around Antarctica (Fig. 8a) developing into cool ocean regions and stadial climate conditions (Fig. 8b).
• Reduced temprature differences between the polar zones and mid-latitudes and thereby weakening of the polar boundaries and the polar jet stream boundary.
• Weakening of the North Atlantic Thermal Circulation.
• Changes in the southern ocean Antarctic oscillation and the Antarctic vortex.

The rapid increase in extreme weather events,including droughts, heat waves, fires, cyclones and storms.

Figure 5. Cenozoic and Anthropocene CO₂ and temperature rise rates.

Figure 6. A comparison between rates of mean global temperature rise during:
(1) the last Glacial Termination (after Shakun et al. 2012);
(2) the PETM (Paleocene-Eocene Thermal Maximum, after Kump 2011);
(3) the late Anthropocene (1750–2019), and
(4) an asteroid impact. In the latter instance, temperature associated with
CO₂ rise would lag by some weeks or months behind aerosol-induced cooling.

Figure 7. An updated Köppen–Geiger climate zones map.

By contrast to linear IPCC climate projections for 2100-2300, climate modelling for the 21st century by Hansen et al. 2016 suggests major effects of ice melt water flow into the oceans from the ice sheets, leading to stadial cooling of parts of the oceans, changing the global temperature pattern from that of the early 21ˢᵗ century (Figs 8, 9a) to the late 21ˢᵗ century (Fig. 9b).

Figure 8. Global temperature patterns during El Nino and La Nina events. NASA GISS

Figure 9. a. An A1B model of surface-air temperature change for 2055-2060 relative
to 1880-1920 (+1 meters sea level rise) for modified forcing (Hansen et al. 2016);
b. A1B model surface-air temperatures in 2096 relative to 1880-1920 (+5 meters sea level rise) for 10 years
ice melt doubling time in the southern hemisphere and partial global cooling of -0.33°C (Hansen et al. 2016).

Summary and conclusions

1. Late 20th century to early 21asrt century global greenhouse gas levels and regional warming rates have reached a high factor to an order of magnitude faster than those of past geological and mass extinction events, with major implications for the nature and speed of extreme weather events.
2. The Anthropocene CO₂ rise and warming rates exceed that of the Last Glacial Termination (LGT) (21–8kyr), the Paleocene-Eocene hyperthermal event (PETM) (55.9 Ma) and the post-impact Cretaceous-Tertiary boundary (K-T) (64.98 Ma). 
3. Further to NASA’s reported mean land-ocean temperature rise of +1.18°C in March 2020, relative to the 1951-1980 baseline, large parts of the continents, including central Asia, west Africa eastern South America and Australia are warming toward mean temperatures of +2°C and higher. 
4. Major consequences of the current shift in state of the climate system pertain to the weakening of the polar boundaries and the migration of climate zones toward the poles. Transient cooling pauses are projected as a result of the flow of cold ice melt water from Greenland and Antarctica into the oceans, leading to stadial cooling intervals.
5. Given the abrupt shift in state of the atmosphere-ocean-cryosphere-land system, the current trend signifies an abrupt shift in state of the atmosphere, accelerating since the mid-20th century. Terms such as climate change and global warming no longer reflect the extreme nature of the climate events consequent on this shift, amounting to a climate catastrophe on a geological scale.

Andrew Glikson

Dr Andrew Glikson
Earth and Paleo-climate scientist
ANU Climate Science Institute

ANU Planetary Science Institute
Canberra, Australian Territory, Australiageospec@iinet.net.au

Books:

The Asteroid Impact Connection of Planetary Evolution
http://www.springer.com/gp/book/9789400763272
The Archaean: Geological and Geochemical Windows into the Early Earth
http://www.springer.com/gp/book/9783319079073
Climate, Fire and Human Evolution: The Deep Time Dimensions of the Anthropocene
http://www.springer.com/gp/book/9783319225111
The Plutocene: Blueprints for a Post-Anthropocene Greenhouse Earth
http://www.springer.com/gp/book/9783319572369
Evolution of the Atmosphere, Fire and the Anthropocene Climate Event Horizon
http://www.springer.com/gp/book/9789400773318
From Stars to Brains: Milestones in the Planetary Evolution of Life and Intelligence
https://www.springer.com/us/book/9783030106027

Asteroids Impacts, Crustal Evolution and Related Mineral Systems with Special Reference to Australia
http://www.springer.com/us/book/9783319745442 

From Stars to Brains: Milestones in the Planetary Evolution of Life and Intelligence

The Plutocene: Blueprints for a Post-Anthropocene Greenhouse Earth

Added below is a video with an August 6, 2019, interview of Andrew Glikson by Guy McPherson and Kevin Hester, as edited by Tim Bob.

Will the Anthropocene last for only 100 years?

On November 9, 2013, methane levels as high as 2662 ppb (parts per billion) were recorded, as indicated by the red dot on the image below.

This image, from an earlier post, gives an idea of the height of this level compared to historic methane levels, and how fast levels of methane (CH4) have been rising compared to levels of two other greenhouse gases, i.e. carbon dioxide (CO2) and nitrous oxide (N2O).

CO2 concentrations in the atmosphere have now risen to levels well above the 400 parts per million (ppm), as illustrated by the graph below, from keelingcurve.ucsd.edu. This 400 ppm is 143% the pre-industrial peak level of 280 ppm.

Paleorecords show that greenhouse gases levels go up and down in lockstep with temperatures in history. The image below shows that carbon dioxide levels back in history typically moved between approximately 180 ppm and 280 ppm, a difference of 100 ppm. Since 1950, CO2 levels have risen by roughly the same difference.

In a fascinating lecture, Dr Jan Zalasiewicz suggests that the Anthropocene started around 1950, when levels of greenhouse gases started to rise exponentially, in line with the rise of fossil fuel use, as also illustrated by the image below.

The image below, from an earlier post, shows that temperatures typically moved up and down by roughly 10 degrees Celsius between a glacial and interglacial phase of the ice ages, suggesting that a 100 ppm rise of carbon dioxide and 300 ppb rise of methane go hand in hand with a 10°C temperature rise.

Many eminent scientists have warned that the high current carbon dioxide levels have already locked us in for a future temperature rise of several degrees Celsius, a rise that is yet to fully manifest itself and that is only held off by the temporary masking effect of sulfur dioxide that is emitted when burning fuel (especially coal) and by the (decreasing) capacity of oceans, ice sheets and glaciers to act as a buffer for heat. Once the masking effect of sulfur dioxide ends and the Arctic sea ice collapses, a huge sudden rise in temperature can be expected, hitting vulnerable pools (see image below) which would accelerate the temperature rise even more and could cause temperatures to rise by another 10°C within decades.

The scenario of such a huge rise in temperature becomes a distinct possibility when considering the combined warming impact of carbon dioxide, methane, nitrous oxide, water vapor and albedo changes, and the vulnerability of some of the terrestrial and marine carbon pools. Also note that, while the above Unesco image gives an estimate of 10⁴ or 10,000 Gt C for ocean methane hydrates, several studies give even higher estimates, as illustrated by the image below, from Pinero et al.

The amount of carbon stored in hydrates globally was in 1992 estimated to be 10,000 Gt (USGS), while a later source gives a figure of 63,400 Gt C for the Klauda & Sandler (2005) estimate of marine hydrates. A warming Gulf Stream is causing methane eruptions off the North American coast. Furthermore, methane appears to be erupting from hydrates on Antarctica, on the Qinghai-Tibetan Plateau and on Greenland. In just one part of the Arctic Ocean alone, the East Siberian Arctic Shelf (ESAS), up to 1700 Gt of methane is contained in sediments in the form of methane hydrates and free gas. A sudden release of just 3% of this amount could add over 50 Gt of methane to the atmosphere, i.e. some seven times what is in the atmosphere now, and experts consider such an amount to be ready for release at any time.

Importantly, methane levels have risen even more strongly than carbon dioxide levels. As the image at the top of this post shows, the current methane level is 250% its pre-industrial peak level, i.e. 1100 ppb above the pre-industrial peak level of 700 ppb. Historically, methane has only moved by some 300 ppb between a glacial and interglacial phase of the ice ages. IPCC/NOAA figures suggest that global mean methane levels have been rising by 5 or 6 ppb annually over recent years and there are some worrying indications that the rise of methane levels might accelerate even further.

To obtain mean methane abundance, measurements are typically taken at an altitude of 586 mb, as methane typically shows up most prominently at this altitude. Indeed, mean methane levels were highest at this altitude in April 2013, at just under 1800 ppb. Looking at mean global methane levels in April 2014 at this altitude, one could at first glance conclude that the situation had not changed much, and that 2014 methane levels had merely risen by a few ppb, in line with IPCC data. So, at first glance one might conclude that there may appear to be only a minimal rise (if any at all) in global mean methane levels when taking measurements at lower altitudes.

The image below illustrates this. What should be added is that the analysis used only selected altitudes and only used part of all data. So, further analysis may be necessary to verify these findings.

Importantly, closer examination of above graph shows that the situation is dramatically different when looking at the rise in methane levels at higher altitudes. A huge rise in mean methane levels appears to have taken place, to the extent that the highest mean level is now reached at 469 mb. Overall, the average rise in methane across the altitudes that are highlighted in the image is no less than 16 ppb.

The table below shows the altitude equivalents in mb (millibar) and feet.

56925 feet	44689 feet	36850 feet	30569 feet	25543 feet	19819 feet	14383 feet	8367 feet	1916 feet
74 mb	147 mb	218 mb	293 mb	367 mb	469 mb	586 mb	742 mb	945 mb

As the image below illustrates, this rise appears to go hand in hand with much higher peak readings, especially at higher altitudes. It appears that the additional methane originates from the higher latitudes of the Northern Hemisphere and has over the past few months moved closer to the equator, which is what typically occurs as methane rises in altitude.

Peak readings in above image are averages over April. On specific days, peak readings could be much higher, e.g. on April 28, 2014, methane levels were recorded as high as 2551 ppb at 469 mb.

As said, there appears to be a 16 ppb rise when comparing global mean methane levels between April 2013 and April 2014. Indeed, the culprit appears to be the rapid rise of methane emissions from hydrates that has been documented by this blog and that I estimated to amount to 99 Tg annually, as illustrated by the image below, from an earlier post.

So, it appears that the rise of methane in the atmosphere is accelerating. What can we expect? As temperatures can be expected to continue to rise and as feedbacks start to kick in, this may well constitute a non-linear trend. The image below shows a polynomial trend that is contained in IPCC AR5 data from 1955 to 2011, so they didn't include this recent steep rise. Nonetheless, the polynomial trendline points at methane reaching mean global levels higher than 3000 ppb by the year 2030. If methane starts to erupt in large quantities from clathrates underneath the seafloor of the Arctic Ocean, this may well be where we are heading.

So, how high could temperatures rise? Worryingly, a non-linear trend is also contained in the temperature data that NASA has gathered over the years, as described in an earlier post. A polynomial trendline points at global temperature anomalies of 5°C by 2060. Even worse, a polynomial trend for the Arctic shows temperature anomalies of 4°C by 2020, 7°C by 2030 and 11°C by 2040, threatening to cause major feedbacks to kick in, including albedo changes and methane releases that will trigger runaway global warming that looks set to eventually catch up with accelerated warming in the Arctic and result in global temperature anomalies of 20°C+ by 2050.

Without action, it appears that the Antropocene will lead to extinction of the very human beings after which the era is named, with the Anthropocene only running from 1950 to 2050, a mere 100 years and much too short to constitute an era. In that case a better name would be the Sixth Extiction Event, as also illustrated by the image below, from an earlier post.

In conclusion, it's high time that we start acting as genuinely wise modern human beings and commit to comprehensive and effective action as discussed at the Climate Plan blog.