Thursday, January 21, 2021

The peril of high atmospheric methane levels

by Andrew Glikson

It is hard to think of a more Orwellian expression than that describing the increase in toxic atmospheric methane gas as “gas-led recovery.”

Several of the large mass extinctions of species in the geological past are attributed to an increase in atmospheric methane (CH₄), raising the temperature of the atmosphere and depriving the oceans from oxygen. Nowadays a serious danger to the atmosphere and for the life support systems ensues from the accelerated release of methane from melting Arctic permafrost, leaks from ocean sediments and from bogs, triggered by global warming. As if this was not dangerous enough, now methane is extracted as coal-seam-gas (CSG) by fracking (hydraulic fracturing) of coal and oil shale in the US, Canada, Australia and elsewhere.

Methane-bearing formations, located about 300m-1000m underground, are fracked using a mixture of water, sand, chemicals and explosives injected into the rock at high pressure, triggering significant amounts of methane leaks into the overlying formations and escaping into the atmosphere (Figure 1).

Figure 1. Schematic illustration of coal-seam-gas fracking (R. Morrison, by permission).

CSG is made primarily of about 95-97% methane, which possesses a radiative greenhouse potential close to X80 times that of carbon dioxide (CO₂). The radiative greenhouse effect of 1 kg methane is equivalent to releasing 84 kg of CO₂ and decreases to 20 and 34 times stronger than CO₂ over a 100-year period.

Global methane deposits (Figure 2) and Australian methane-bearing basins (Figure 3) are proliferating. Fugitive emissions from CSG are already enhancing the concentration of atmospheric methane above drill sites and range from 1 to 9 percent during the total life cycle emissions. The venting of methane from underground coal mines in the Hunter region of New South Wales has led to an atmospheric level in the region of 3,000 parts per billion, with methane levels of 2,000 ppb (parts per billion) extending to some 50 km away from the mines. Peak readings in excess of 3000 ppb represent an amalgamation of plumes from 17 sources. The median concentration within this section was 1820 ppb, with a peak reading of 2110 ppb. Compare this with mean methane values at Mouna Loa, Hawaii, of 1884 ppb.

Figure 2. Global gas hydrate potential regions.

Fugitive methane emissions from natural, urban, agricultural, and energy-production landscapes of eastern Australia. The chemical signature of methane released from fracking is found in the atmosphere points to shale gas operations as the source.


Figure 3. Australian basins, oil and gas resources.

The accumulation of many hundreds of billions tons of unoxidized methane-rich organic matter in Arctic permafrost, methane hydrates in shallow Arctic lakes and seas, bogs, and as emanated from cattle and sheep, has already enhanced global methane growth over the last 40 years at rates up to 14 ppb/year (Figure 4).


Figure 4. Growth of atmospheric methane, Mouna Loa, Hawaii,
between 1980-2020 and 2017-2020. NOAA.

The current methane level of 1884 ppb, ~2.5 times the <800 ppb level in 1840AD, indicating a mean growth rate of ~7 ppb/year (Figure 4), is attributable to in part to animal husbandry, permafrost melting, release from marine hydrates and bogs, and in part emissions from shale gas and fracking. as in the United States and Canada.

High levels of methane reduce the amount of oxygen breathed from the air, with health consequences. The toxicity of methane is corroborated in a 2018 study in Pennsylvania showing children born within a mile or two of a gas well were likely to be smaller and less healthy. New York State, Maryland, and Vermont have banned fracking, as have France and Germany.

According to Hansen (2018) reserves of unconventional gas exceed 10,000 GtC (billion tons carbon). Given the scale of methane hydrate deposits around the world (Figure 5), sufficient deposits exist to perpetrate a global mass extinction of species on a geological scale.¹ 

Figure 5. Estimates of methane held in hydrates worldwide. Estimates of the Methane Held in Hydrates Worldwide. Early estimates for marine hydrates (encompassed by the green region), made before hydrate had been recovered in the marine environment, are high because they assume gas hydrates exist in essentially all the world’s oceanic sediments. Subsequent estimates are lower, but remain widely scattered (encompassed by the blue region) because of continued uncertainty in the non-uniform, heterogeneous distribution of organic carbon from which the methane in hydrate is generated, as well as uncertainties in the efficiency with which that methane is produced and then captured in gas hydrate. Nonetheless, marine hydrates are expected to contain one to two orders of magnitude more methane than exists in natural gas reserves worldwide (brown square) (U.S. Energy Information Administration 2010). Continental hydrate mass estimates (encompassed by the pink region) tend to be about 1 per cent of the marine estimates.


¹ For 2.12 billion ton of carbon (GtC) raising atmospheric CO₂ by 1ppm, and assuming about 50% of CO₂ remaining in the atmosphere, future drilling and fracking could in principle raise atmospheric CO₂ level to about or more than 2000 ppm.


Andrew Glikson

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




Friday, January 15, 2021

2020: Hottest Year On Record

NASA data show that 2020 was the hottest year on record.



The image below shows that high temperature in 2020 hit Siberia and the Arctic Ocean.

In above images, the temperature anomaly is compared to 1951-1980, NASA's default baseline. When using an earlier baseline, the data need to be adjusted. The image below shows a trendline pointing at an 0.31°C adjustment for a 1900 baseline. 



Additional adjustment is needed when using a 1750 baseline, while it also makes sense to add further adjustment for higher polar anomalies and for air temperatures over oceans, rather than sea surface water temperatures. In total, a 0.78°C adjustment seems appropriate, as has been applied before, such as in this analysis. For the year 2020, this translates in a temperature rise of 1.8029°C versus the year 1750.

Three trends: blue, purple and red

Will the global temperature rise to 3°C above 1750 by 2026? The blue trend below is based on 1880-2020 NASA Land+Ocean data and adjusted by 0.78°C to reflect a 1750 baseline, ocean air temperatures and higher polar anomalies, and it crosses a 3°C rise in 2026.



The trend shows a temperature for 2020 that is slightly higher than indicated by the data. This is in line with the fact that we're currently in a La Niña period and that we're also at a low point in the sunspot cycle, as discussed in an earlier post. The blue trend also shows that the 1.5°C treshold was already crossed even before the Paris Agreement was accepted. 



The second (purple) trend is based on a shorter period, i.e. 2006-2020 NASA land+ocean (LOTI) data, again adjusted by 0.78°C to reflect a 1750 baseline, ocean air temperatures and higher polar anomalies. The trend approaches 10°C above 1750 by 2026. The trend is based on 15 years of data, making it span a 30-year period centered around end 2020 when extended into the future for a similar 15 year period. The trend approaches 10°C above 1750 in 2026.

The trend is displayed on the backdrop of an image from an earlier post, showing how a 10°C rise could eventuate by 2026 when adding up the impact of warming elements and their interaction.



The stacked bars are somewhat higher than the trend. Keep in mind that the stacked bars are for the month February, when anomalies can be significantly higher than the annual average.

Temperature rise for February 2016 versus 1900.
In the NASA image on the right, the February 2016 temperature was 1.70°C above 1900 (i.e. 1885-1914). In the stacked-bar analysis, the February 2016 rise from 1900 was conservately given a value of 1.62°C, which was extended into the future, while an additional 0.3°C was added for temperature rise from pre-industrial to 1900.

Later analyses such as this one also added a further 0.2°C to the temperature rise, to reflect ocean air temperatures (rather than water temperatures) and higher polar anomalies (note the grey areas on the image in the right).

Anyway, the image shows two types of analysis on top of each other, one analysis based on trend analysis and another analysis based on a model using high values for the various warming elements. The stacked-bar analysis actually doesn't reflect the worst-case scenario, an even faster rise is illustrated by the next trend, the red line.

The third (red) trend suggests that we may have crossed the 2°C treshold in the year 2020. The trend is based on a recent period (2009-2020) of the NASA land+ocean data, again adjusted by 0.78°C to reflect a 1750 baseline, ocean air temperatures and higher polar anomalies.




Where do we go from here? 

It's important to acknowledge the danger of acceleration of the temperature rise over the next few years. The threat is illustrated by the image below and shows up most prominently in the red trend. 


Of the three trends, the red trend is based on the shortest period, and it does indicate that we have aready crossed the 2°C treshold and we could be facing an even steeper temperature rise over the next few years.

We're in a La Niña period and we're also at a low point in the sunspot cycle. This suppresses the temperature somewhat, so the 2020 temperature should actually be adjusted upward to compensate for such variables. Importantly, while such variables do show up more when basing trends on shorter periods, the data have not be adjusted for this in this case, so the situation could actually be even worse. 

At a 3°C rise, humans will likely go extinct, while most life on Earth will disappear with a 5°C rise, and as the temperature keeps rising, oceans will evaporate and Earth will go the same way as Venus, a 2019 analysis warned. 

Dangerous acceleration of the temperature rise 

There are many potential causes behind the acceleration of the temperature rise, such as the fact that the strongest impact of carbon dioxide is felt ten years after emission, so we are yet to experience the full wrath of the carbon dioxide emitted over the past decade. However, this doesn't explain why 2020 turned out to be the hottest year on record, as opposed to - say - 2019, given that in 2020 carbon dioxide emissions were 7% lower than in 2019.

James Hansen confirms that the temperature rise is accelerating, and he points at aerosols as the cause. However, most cooling aerosols come from industries such as smelters and coal-fired power plants that have hardly reduced their operations in 2020, as illustrated by the image below, from the aerosols page


Above image shows that on December 17, 2020, at 10:00 UTC, sulfate aerosols (SO₄) were as high as 6.396 τ at the green circle. Wind on the image is measured at 850 hPa.

Could the land sink be decreasing? A recent study shows that the mean temperature of the warmest quarter (3-month period) passed the thermal maximum for photosynthesis during the past decade. At higher temperatures, respiration rates continue to rise in contrast to sharply declining rates of photosynthesis. Under business-as-usual emissions, this divergence elicits a near halving of the land sink strength by as early as 2040. While this is a frightening prospect, it still doesn't explain why 2020 turned out to be the hottest year on record. 

Oceans are taking up less heat, thus leaving more heat in the atmosphere. The danger is illustrated by the image below. 


The white band around -60° (South) indicates that the Southern Ocean has not yet caught up with global warming, featuring low-level clouds that reflect sunlight back into space. Over time, the low clouds will decrease, which will allow more sunlight to be absorbed by Earth and give the world additional warming. A recent study finds that, after this 'pattern effect' is accounted for, committed global warming at present-day forcing rises by 0.7°C. While this is very worrying, it still doesn't explain why 2020 turned out to be the hottest year on record. 

Ocean stratification contributes to further surface warming, concludes another recent study
"The stronger ocean warming within upper layers versus deep water has caused an increase of ocean stratification in the past half century. With increased stratification, heat from climate warming less effectively penetrates into the deep ocean, which contributes to further surface warming. It also reduces the capability of the ocean to store carbon, exacerbating global surface warming. Furthermore, climate warming prevents the vertical exchanges of nutrients and oxygen, thus impacting the food supply of whole marine ecosystems."
"By uptaking ~90% of anthropogenic heat and ~30% of the carbon emissions, the ocean buffers global warming. [The] ocean has already absorbed an immense amount of heat, and will continue to absorb excess energy in the Earth’s system until atmospheric carbon levels are significantly lowered. In other words, the excess heat already in the ocean, and heat likely to enter the ocean in the coming years, will continue to affect weather patterns, sea level, and ocean biota for some time, even under zero carbon emission conditions."
Many feedbacks are starting to kick in with greater ferocity, with tipping points threatening to get crossed or already crossed, such as the latent heat tipping point, i.e. loss of the ocean heat buffer, as Arctic sea ice keeps getting thinner. As the above map also shows, the temperature rise is hitting the Arctic Ocean particularly hard. At least ten tipping points are affecting the Arctic, including the latent heat tipping point and the methane hydrates tipping point, as illustrated by the image below.
 
[ from an earlier post ]

A combination of higher temperatures and the resulting feedbacks such as stronger ocean stratification, stronger wind, decline of Arctic snow and ice and a distorted Jet Stream is threatening to cause formation of a lid at the surface of the North Atlantic Ocean that enables more heat to move to the Arctic Ocean. This could cause huge amounts of methane to erupt from the seafloor, thus contributing to cause the 1,200 ppm CO₂e cloud tipping point to get crossed, resulting in an extra 8°C rise, as an earlier post and a recent post warned.

Dangerous acceleration of the temperature rise

The danger is that methane is erupting in the Arctic from the seafloor and that this increasingly contributes to methane reaching the stratosphere. 

While methane initially is very potent in heating up the atmosphere, it is generally broken down relatively quickly, but in the atmosphere over the Arctic, there is very little hydroxyl to break down the methane. 

Methane also persists much longer in the stratosphere, which contributes to its accumulation there. 


Large amounts of methane may already be erupting from the seafloor of the Arctic Ocean, rising rapidly and even reaching the stratosphere

This danger is getting little public attention. The NOAA image on the right shows the globally-averaged, monthly mean atmospheric methane abundance derived from measurements from marine surface sites. Measurements that are taken at sea level do not reflect methane very well that is rising up from the seafloor of the Arctic Ocean, especially where the methane rises up high in plumes. 

Satellite measurements better reflect the danger. The image on the right shows that the MetOp-1 satellite recorded peak methane levels as high as 2715 ppb at 469 mb on the morning of January 6, 2021. 

Most of the high (magenta-colored) levels of methane are located over oceans and a lot of them over the Arctic Ocean. 

The next image on the right shows the situation closer to sea level, at 586 mb, where even less of the high levels of methane show up over land, indicating that the methane originated from the seafloor. 

The third image on the righ shows the situation even closer to sea level, at 742 mb, and almost all high levels of methane show up over the Arctic Ocean and over areas where the Atlantic Ocean and the Pacific Ocean border on the Arctic. 

Because methane is lighter than air and much lighter than water, methane erupting from the seafloor will quickly rise up vertically. While much of the methane that is released from the seabed can get broken down in the water by microbes, methane that is rising rapidly and highly concentrated in the form of plumes will leave little opportunity for microbes to break it down in the water column, especially where waters are shallow,
as is the case in much of the Arctic Ocean.

As methane hydrates destabilize, methane will erupt with an explosive force, since methane is highly compressed inside the hydrate (1 m³ of methane hydrate can release 160 m³ of gas). Such eruptions can destabilize further hydrates located nearby. Because of this explosive force, plumes of methane can rise at high speed through the water column. 

Because methane is so much lighter than water, large methane releases from the seafloor will form larger bubbles that merge and stick together, developing more thrust as they rise through the water.

Because of this thrust, methane plumes will keep rising rapidly after entering the atmosphere, and the plumes will more easily push away aerosols and gases that slow down the rise in the air of methane elsewhere, such as where methane is emitted by cows. 

A further image of another satellite is added on the right. The N2O satellite recorded methane levels as high as 2817 ppb at 487 mb on the morning of January 10, 2021. 

Such sudden and very high peaks can hardly be caused by agriculture or wetlands, but instead they are likely caused by destabilization of methane hydrates in sediments at the seafloor. 

Further contributing to the danger is the fact that little hydroxyl is present in the atmosphere over the Arctic, so it is much harder for this methane to get broken down in the air over the Arctic, compared to methane emissions elsewhere. 

Finally, the edge of the stratosphere is much lower over the Arctic, as discussed in an earlier post.

All this makes that methane that is erupting from the seafloor of the Arctic Ocean is more prone to accumulate in the stratosphere. Once methane is in the stratosphere, it's unlikely that it will come back into the troposphere.

The IPCC AR5 (2013) gave methane a lifetime of 12.4 years. The IPCC TAR (2001) gave stratospheric methane a lifetime of 120 years, adding that less than 7% of methane did reach the stratosphere at the time. According to IPCC AR5, of the methane that gets broken down by hydroxyl in the atmosphere, some 8.5% got broken down in the stratosphere.

Conclusions

The situation is dire and calls for immediate, comprehensive and effective action as described in the Climate Plan.

In the video below, Paul Beckwith discusses the situation: 


For another perspective, Guy McPherson discusses the situation in the video below, Edge of Extinction: Maybe I’m Wrong





Links

• Climate Plan
https://arctic-news.blogspot.com/p/climateplan.html

• NASA Global Land-Ocean Temperature Index
https://data.giss.nasa.gov/gistemp

• What are El Niño and La Niña?
https://oceanservice.noaa.gov/facts/ninonina.html

• Multivariate El Niño/Southern Oscillation (ENSO) Index Version 2 (MEI.v2)
https://psl.noaa.gov/enso/mei 
 
• Temperatures keep rising
https://arctic-news.blogspot.com/2020/12/temperatures-keep-rising.html

• There is no time to lose
https://arctic-news.blogspot.com/2020/11/there-is-no-time-to-lose.html

• Possible climate transitions from breakup of stratocumulus decks under greenhouse warming, by Tapio Schneider et al. (2019)
https://www.nature.com/articles/s41561-019-0310-1

• A rise of 18°C or 32.4°F by 2026?

• Greater committed warming after accounting for the pattern effect - by Chen Zhou et al. 

• Upper Ocean Temperatures Hit Record High in 2020 - by Lijing Cheng et al. 
https://link.springer.com/article/10.1007/s00376-021-0447-x

• How close are we to the temperature tipping point of the terrestrial biosphere? - by Katharyn Duffy et al.
https://advances.sciencemag.org/content/7/3/eaay1052

• Methane hydrates tipping point threatens to get crossed

• Cold freshwater lid on North Atlantic

• Aerosols

• NOAA - Trends in Atmospheric Methane
https://www.esrl.noaa.gov/gmd/ccgg/trends_ch4

•  COVID-19 lockdown causes unprecedented drop in global CO2 emissions in 2020 - Gobal Carbon Project
https://www.globalcarbonproject.org/carbonbudget/20/files/International_FutureEarth_GCB2020.pdf

• Global Average Temperatures in 2020 Reached a RECORD HIGH of 1.55 C above PreIndustrial in 1750 - by Paul Beckwith 
https://www.youtube.com/watch?v=O0lgTAEUYyA

• Edge of Extinction: Maybe I’m Wrong - by Guy McPherson
https://guymcpherson.com/2021/01/edge-of-extinction-maybe-im-wrong

• Extinction
https://arctic-news.blogspot.com/p/extinction.html


Tuesday, December 22, 2020

An Orwellian climate while Rome burns

 by Andrew Glikson

The definition of insanity is doing the same thing over and over and expecting different results. - Albert Einstein.


As the world is trying to hopefully recover from the tragic effects of COVID-19, it is reminded there is no vaccine for the existential threat for its life support systems posed by global warming, nor for the looming threats of future wars and nuclear wars fueled by warmongers and $trillion preparations by military-industrial complexes.

Between 1740 and 1897 some 230 wars and revolutions in Europe suggested war remained deeply ingrained in the human psyche and civilization. The question is whether the currently approaching catastrophes can be averted.

No one wishes to believe in the projections made in the recent book ‘The Uninhabitable Earth’, except that these projections, made by David Wallace-Wells, are disturbingly consistent with the current shift in state of the climate toward +4 degrees and even +6 degrees Celsius above pre-industrial levels, as indicated by the current trends (Figure 1) and conveyed by leading climate scientists and the International Panel for Climate Change (IPCC). 

Figure 1.Global mean temperature estimates for land areas (NASA).

Facing the unthinkable consequences of global warming is pushing climate scientists into a quandary. In private conversations, many scientists express far greater concern at the trend of global warming than they do in public. However, faced with social and psychological barriers, as well as threats of losing positions and jobs, in business, public service and academia, a majority keeps silent, displaying lesser courage than school children.

According to James Hansen (2012), NASA’s former chief climate scientist: “You can’t burn all of these fossil fuels without creating a different planet”. According to Joachim Schellnhuber (2015), Germany’s chief climate scientist: ‘We’re simply talking about the very life support system of this planet’, and ‘If we don’t solve the climate crisis, we can forget about the rest’.

Referring to a phenomenon he termed “scientific reticence”, James Hansen (2007) states: “I suggest that a “scientific reticence” (namely a reluctance to convey worrying news) is inhibiting the communication of a threat of a potentially large sea level rise”.

According to Bajaj (2019): “when it comes to climate change, the need for excessive caution and absolute certainty of the results is manifesting as silence from the mainstream science on the worst yet probable consequences and the worst-case scenarios that are looking increasingly likely”. A paradox emerges where scientists who experience scientific reticence are still accused of being alarmists.

This is because an evaluation of the probability of a risk needs to be related to the magnitude of the risk. For example, the inspection of the engines of a Jumbo Jet carrying 300 passengers need to be even more rigorous than that of a commuter van, or evaluation of the risk posed by a potential failure of a nuclear reactor even more critical than that of a conventional power plant, as is the absolute safety of a particle accelerator.

By analogy with the dictum Those who do not learn from history are doomed to repeat it projections of future climate trajectories need to take account of studies of the past behaviour of the atmosphere-ocean system. The pace of current global warming exceeds those of the last 2.6 million years by an order of magnitude, with calamitous consequences for biological systems.

As indicated by the basic laws of physics, the principles of climate science and empirical observations in nature, under an increase of greenhouse gas concentrations by about 50 percent , global warming is inevitable. While modeled future climate change trajectories may vary, depending whether observations are based on recent measurements, paleoclimate data or models, the consequences of such an increase are inevitably catastrophic. Whereas IPCC models portray linear warming trends to 2300, other models take account of the flow of ice melt water from Greenland and Antarctica into the oceans and thereby irregular warming (Glikson, 2019).

Given the warnings issued by leading climate scientists and the IPCC, while nations keep investing their dwindling $trillions in its military-industrial complexes in preparations for future war/s, our world is losing its last chance to save its planetary life support systems


Andrew Glikson

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




Tuesday, December 15, 2020

Temperatures keep rising


Temperatures keep rising. Above image uses NASA data that are adjusted to reflect a 1750 baseline, ocean air temperatures and higher polar anomalies, while showing anomalies going back to September 2011, adding a blue trend going back to 1880 and a red trend going back to September 2011. 

The map below also shows that in November 2020, especially the Arctic Ocean, again was very hot.


Anomalies in the above NASA image are compared to 1951-1980, while NOAA's default baseline for temperature anomalies is the 20th century average. In the Copernicus image below anomalies are compared to the 1981-2010 average. 

Using a different baseline can make a lot of difference. An earlier analysis pointed out that, when using a 1750 baseline and when using ocean air temperatures and higher Arctic anomalies, we did already cross  2°C above pre-industrial in February 2020.  

Above Copernicus image shows temperatures averaged over the twelve-month period from December 2019 to November 2020. The image shows that the shape of the global anomaly over the past twelve months is very similar to the peak reached around 2016. This confirms that global heating is accelerating, because the peak around 2016 was reached under strong El Niño conditions, whereas current temperatures are reached under La Niña conditions. Furthermore, sunspots are currently low. The La Niña and the low sunspots are both suppressing temperatures, as discussed in a recent post.

Future rise?

By how much will temperatures rise over the next few years?


Above image, from the U.N. Emissions Gap Report 2020, shows that growth in greenhouse gas emissions continued in 2019, with emissions reaching a total of 59.1 GtCO₂e. The commitments promised at the Paris Agreement in 2015 were not enough to limit the temperature rise to 1.5°C and those commentments were not even met, said António Guterres, United Nations Secretary-General, calling on all nations to declare a state of Climate Emergency until carbon neutrality is reached. Earlier, António Guterres had said: "We are headed for a thundering temperature rise of 3 to 5 degrees Celsius this century." 

What could cause a steep temperature rise over the next few years? 

A temperature rise of more than 3°C above pre-industrial could occur, and this could actually happen within a few years time. There are a number of reasons why the temperature rise could take place so fast, as described below.

As said, the temperature is currently suppressed by the current La Niña and the currently low sunspots (Hansen et al. give the sunpot cycle an amplitude of some 0.25 W/m²). Such short-term differences show up more in the red trend of the image at the top, which uses a polynomial trend over a short period. 

Compensating for the fact that sunspots are currently low and the fact that we're currently a La Niña period can already push the temperature anomaly well over the 2°C threshold that politicians at the Paris Agreement pledged would not be crossed.  


The above NOAA image and the NOAA image below illustrate that we are currently experiencing La Niña conditions
 

How long will it take before we'll reach the peak of the next El Niño? NOAA says:
El Niño and La Niña episodes typically last nine to 12 months, but some prolonged events may last for years. While their frequency can be quite irregular, El Niño and La Niña events occur on average every two to seven years. Typically, El Niño occurs more frequently than La Niña.
There are further reasons why the temperature rise could strongly accelerate over the next few years. Loss of cooling aerosols is one such reason. Another reason is the growing frequency and intensity of forest fires, which come with high emissions of methane, of heating aerosols such as black carbon and brown carbon, and of carbon monoxide that causes hydroxyl depletion, thus extending the lifetime of methane and heating aeosols. 

Map from earlier postThe vertical axis depicts
latitude, t
he North Pole is at the top (90° North),
the Equator in the 
middle (0°) and the South Pole 
at the bottom (-90° South). GHCN v4 land-surface
air + ERSST v5 sea-surface water temperature 
anomaly. The Arctic anomaly reaches 4.83°C or 
8.69°F 
vs 1951-1980, and 5.57°C vs 1885-1914.
A hotter world will will also hold more water vapor, a potent greenhouse gas. 
 
Furthermore, many tipping points affect the Arctic, e.g. more methane and nitrous oxide emissions can be expected to result from continued decline of what once was permafrost. 

The temperature rise is felt the strongest in the Arctic, as illustrated by the zonal mean temperature anomaly map on the right, from an earlier post.

As one of the tipping points gets crossed in the Arctic, multiple feedbacks can start kicking in more strongly, resulting in multiple additional tipping points to subsequently get crossed. 
 
At least ten tipping points affect the Arctic, as described in an earlier post, and it looks like the latent heat tipping point has already been crossed, as illustrated by the image below, from an earlier post, which shows two such tipping points. 
 
[ from an earlier post ]

Huge temperature rise

When extending the vertical axis of the image at the top, a picture emerges that shows that a temperature rise of more than 13°C above 1750 could happen by 2026. The trend shows that 10°C is crossed in February 2026, while an additional rise of 3°C takes place in the course of 2026. The temperature could rise this much, in part because at 1200 ppm CO₂e the cloud feedback will start to kick in, which in itself can raise temperatures by an additional 8°C.


And the rise wouldn't stop there! Even when adding up the impact of only the existing carbon dioxide and methane levels, and then adding large releases of seafloor methane, this alone could suffice to trigger the cloud feedback, as described in an earlier post

Of course, there are further warming elements, in addition to carbon dioxide and methane, and they could jointly cause a rise of 10°C by 2026 even in case of smaller releases of seafloor methane, as illustrated by the image below. 
 
[ from an earlier post ]

[ from an earlier post ]
Above image illustrates how a temperature rise of more than as 10°C could eventuate as early as February 2026 when taking into account aerosol changes, albedo changes, water vapor, nitrous oxide, etc., as discussed in an earlier analysis

The joint impact of all warming elements, including the cloud feedback, threatens to cause a total rise of 18°C, as an earlier post warned, adding the image on the right. 

How high could the temperature rise? At a 3°C rise, humans will likely go extinct, while most life on Earth will disappear with a 5°C rise, and as the temperature keeps rising, oceans will evaporate and Earth will go the same way as Venus, a 2019 analysis warned. 

The situation is dire and calls for immediate, comprehensive and effective action, as described in the Climate Plan.



Links

• Climate Plan
https://arctic-news.blogspot.com/p/climateplan.html

• NOAA Global Climate Report - November 2020
https://www.ncdc.noaa.gov/sotc/global/202011

• NASA GISS Surface Temperature Analysis - maps
https://data.giss.nasa.gov/gistemp/maps/index.html

• What are El Niño and La Niña?
https://oceanservice.noaa.gov/facts/ninonina.html

• Multivariate El Niño/Southern Oscillation (ENSO) Index Version 2 (MEI.v2)
https://psl.noaa.gov/enso/mei

• Copernicus - surface air temperature for Novmber 2020
https://climate.copernicus.eu/surface-air-temperature-october-2020

• NOAA ISIS Solar Cycle Sunspot Number Progression
https://www.swpc.noaa.gov/products/solar-cycle-progression

• Secretary-General's address at Columbia University: "The State of the Planet"
https://www.un.org/sg/en/content/sg/speeches/2020-12-02/address-columbia-university-the-state-of-the-planet

• U.N. Emissions Gap Report 2020 
https://www.unenvironment.org/emissions-gap-report-2020

• U.N. Climate Ambitions Summit, December 12, 2020
https://www.climateambitionsummit2020.org/ondemand.php

• U.N. Paris Agreement (2015)
https://unfccc.int/process-and-meetings/the-paris-agreement/the-paris-agreement

• Why stronger winds over the North Atlantic are so dangerous
https://arctic-news.blogspot.com/2020/02/why-stronger-winds-over-north-atlantic-are-so-dangerous.html

• Feedbacks in the Arctic
https://arctic-news.blogspot.com/p/feedbacks.html

• September 2015 Sea Surface Warmest On Record
https://arctic-news.blogspot.com/2015/10/september-2015-sea-surface-warmest-on-record.html

• When will we die?
https://arctic-news.blogspot.com/2019/06/when-will-we-die.html

• A rise of 18°C or 32.4°F by 2026?
https://arctic-news.blogspot.com/2019/02/a-rise-of-18c-or-324f-by-2026.html

• Methane Hydrates Tipping Point threatens to get crossed
https://arctic-news.blogspot.com/2020/08/methane-hydrates-tipping-point-threatens-to-get-crossed.html

• Arctic Hit By Ten Tipping Points
https://arctic-news.blogspot.com/2020/04/arctic-hit-by-ten-tipping-points.html

• Crossing the Paris Agreement thresholds
https://arctic-news.blogspot.com/p/crossing.html

• 2°C crossed
https://arctic-news.blogspot.com/2020/03/2c-crossed.html

• Most Important Message Ever
https://arctic-news.blogspot.com/2019/07/most-important-message-ever.html

• Blue Ocean Event
https://arctic-news.blogspot.com/2018/09/blue-ocean-event.html

• Record Arctic Warming
https://arctic-news.blogspot.com/2016/04/record-arctic-warming.html

• There is no time to lose
https://arctic-news.blogspot.com/2020/11/there-is-no-time-to-lose.html

• Temperatures threaten to become unbearable
https://arctic-news.blogspot.com/2020/09/temperatures-threaten-to-become-unbearable.html

• Warning of mass extinction of species, including humans, within one decade
https://arctic-news.blogspot.com/2017/02/warning-of-mass-extinction-of-species-including-humans-within-one-decade.html

• Extinction
https://arctic-news.blogspot.com/p/extinction.html