Models downplay wrath of what they sow

Models that analyze what is driving up the temperature all too often omit specific sources, or when included, models all too often downplay their contribution. Accordingly, policies that are promoted based on such models are all too often ineffective or even counter-productive. 

Methane is all too often referred to as 'natural gas' originating from wetlands, swamps, cows and pigs, as if calling methane 'natural' implied that human activities were not responsible for such emissions. Moreover, people with vested interests all too often suggest that such 'natural emissions' should be captured and used for heating, cooking or industrial purposes, to offset 'human emissions'. Similarly, forest fires are all too often referred to as 'wildfires', as if human activities were not responsible for them. 

The compilation of images below shows forest fires as the largest source of carbon dioxide emissions on October 26, 2024. An image of carbon monoxide is also added (bottom right), as carbon monoxide is an indicator of forest fires. Carbon monoxide is also important since it is a precursor of tropospheric ozone and carbon monoxide depletes tropospheric hydroxyl radicals, thus extending methane's lifetime. 

The methane image (top right) shows a high presence of methane in northern Europe. The cause for this is the high temperatures anomaly in northern Europe on October 26, 2024, resulting in strong decomposition of vegetation, which comes with high emissions of carbon dioxide, carbon monoxide and methane. 

The high temperatures anomaly in northern Europe is illustrated by the above image. The image also illustrates polar amplification of the temperature rise, one of the mechanisms that drives up the temperature rise. Numerous mechanisms driving up the temperature rise are discussed in an earlier post that warns about a Double Blue Ocean Event. Thawing permafrost can cause huge emissions of carbon dioxide (CO₂), methane and nitrous oxide. 

[ from earlier post ]

Rising emissions could originate from many sources, the more so as more sinks turn into sources.

[ from earlier post ]

Many models go back only to 1750, many even use an earlier base, as if concentrations of greenhouse gases only started to rise then. 

The image on the right shows IPCC and WMO values for the rise of methane (CH₄), carbon dioxide (CO₂) and nitrous oxide (N₂O) from 1750. The image shows that: 

- Methane rose to 265% its 1750 value. - Carbon dioxide rose to 151% its 1750 value.
- Nitrous oxide rose to 125% its 1750 value.

Note that values for methane as low as 550 ppb and carbon dioxide as low as 260 ppm have been found in ice cores corresponding with periods thousands of years ago, as illustrated by the image below, from the pre-industrial page, based on Ruddiman et al. (2015). 

According to the Met Office, climate sensitivity is typically defined as the global temperature rise following a doubling of CO₂ concentration in the atmosphere compared to pre-industrial levels. Pre-industrial CO₂ was about 260 parts per million (ppm), so a doubling would be at roughly 520 ppm.

A recent study found that doubling the atmospheric CO₂ levels could cause an increase in Earth’s average temperature of 7 to 14°C (13 to 25.2°F). In the video below, Guy McPherson discusses the study.

How fast could a rise to 520 ppm CO₂ unfold? Models typically put 520 ppm CO₂ far away in the future. The image below shows an analysis based on August 2009 through July 2024 data that has a trend added pointing at 520 ppm CO₂ getting crossed in 2029 and 1200 ppm CO₂ getting crossed in early 2035. In other words, the clouds tipping point could get crossed in early 2035 due to rising CO₂ alone, and because this tipping point is measured in CO₂e, this could occur well before 2035 when including the impact of feedbacks and further mechanisms.

[ from earlier post ]

Another way the danger of rising temperatures is all too often downplayed is to suggest that many feedbacks work only over very long timescales. This narrative may be convenient for politicians who rarely bother about what happens beyond the next election. However, as discussed in a recent post, there are many mechanisms that can push up the temperature rapidly, adding up to a potential rise of more than 18°C within years.

Climate Emergency Declaration

Instead of omitting them, all mechanisms driving up the temperature should be fully included in an action plan that seeks to improve the situation. Multiple policy instruments and combinations of policy instruments should be considered for implementation, preferably through local feebates. 

The situation is dire and the precautionary principle calls for rapid, comprehensive and effective action to reduce the damage and to improve the situation, as described in this 2022 post, where needed in combination with a Climate Emergency Declaration, as discussed at this group.

Links

• Copernicus - Climate Pulse
https://atmosphere.climate.copernicus.eu

• Climate Reanalyzer 
https://climatereanalyzer.org

• World Meteorological Organization (WMO) - Greenhouse Gas Bulletin - No. 20 – 28 October 2024

https://library.wmo.int/records/item/69057-no-20-28-october-2024

• Double Blue Ocean Event 2025? 

https://arctic-news.blogspot.com/2024/10/double-blue-ocean-event-2025.html

• Continuous sterane and phytane δ13C record reveals a substantial pCO2 decline since the mid-Miocene - by Caitlyn R. Witkowski et al. (2024) 

https://www.nature.com/articles/s41467-024-47676-9
discussed on facebook at: 
https://www.facebook.com/groups/arcticnews/posts/10161491643879679

• Guy McPherson - Science Snippets: Earth's Temperature Could Exceed 14 C
https://www.youtube.com/watch?v=7jBWl5s7wzo

• Transforming Society
https://arctic-news.blogspot.com/2022/10/transforming-society.html

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

• Climate Emergency Declaration
https://arctic-news.blogspot.com/p/climate-emergency-declaration.html

Is CMIP6 SSP585 the worst-case scenario?

The image below, adapted from Climate Reanalyzer, shows the temperature in the year 2100, in a CMIP6 SSP585 scenario. The image shows how much the temperature will have risen in 2100, at 2 meters above the surface and compared to the period 1979-2000. 

The image below shows a progressive temperature rise reaching 4.589°C in 2100 compared to the same period, i.e. 1979-2000 and in a CMIP6 SSP585 scenario.

The 1979-2000 period is relatively recent. The temperature has been rising for longer than that. The image below shows a progressive temperature rise reaching 4.91°C by 2100 in a CMIP6 SSP585 scenario when instead using a 1901-2000 period as a base.

The 1901-2000 period is also relatively recent, much later than pre-industrial. When using a pre-industrial base, the temperature rise will be well over 5°C.

As illustrated by the top image, the temperature rise over land will be much higher than over oceans, which makes the situation even more dire, given that most people live on land and could face a rise of  8°C by 2100 in a CMIP6 SSP585 scenario.

In a CMIP6 SSP585 scenario, temperatures are projected to keep rising strongly beyond 2100, as illustrated by the image below, from a 2016 paper by Brian O'Neill et al.

In the study by Brian O'Neill et al., CO₂ emissions keep rising until 2100, to then fall gradually to current levels, while the CO₂ concentration in the atmosphere keep rising, to remain at levels beyond 2000 ppm and result in a temperature rise of 8°C by 2300 in a CMIP6 SSP585 scenario.

Is CMIP6 SSP585 the worst-case scenario?

To check whether CMIP6 SSP585 is indeed the worst-case scenario, one can look at how fast CO₂ is rising. According to the IEA, global energy-related CO₂ emissions grew in 2023, reaching a new record high of 37.4 Gt (or 10.098 GtC). The image below, from a recent post, confirms the recent acceleration in CO₂ concentrations, while showing the potential for CO₂ concentration to cross 1200 ppm before the year 2060.

In other words, CO₂ may well be rising even faster than anticipated in a CMIP6 SSP585 scenario, while this scenario doesn't take into account the potential for CO₂e concentrations to cross 1200 ppm much earlier than 2100 (inset), e.g. before 2060 as illustrated by the red trend in the main image. Furthermore, CMIP6 SSP585 doesn't take into account that, in addition to the temperature rise resulting from high greenhouse gas concentrations, crossing the clouds tipping point at 1200 ppm in itself would push up temperatures by a further 8°C.

Indeed, the clouds tipping point could be crossed even earlier when also taking into account methane, nitrous oxide and further greenhouse gases, while there are additional developments such as organic carbon and inorganic carbon release from soils that could further raise both CO₂ concentrations and temperatures. The Extinction page and posts such as this one and this one warn about the potential for a temperature rise of well over 18°C unfolding as early as 2026. 

In conclusion, the temperature looks set to be rising higher and faster at accelerating rate, dwarfing anything seen in previous extinction events, as illustrated by the image below, from an earlier post.

"Now I am become Death, the destroyer of worlds."

The above image is a screenshot from the video (further above) in which physicist J. Robert Oppenheimer reflects on the first test of the atomic bomb. His haunting words mark the moment when science met conscience.

Similarly, climate change is a destroyer of worlds with unfathomable consequences, yet politicians refuse to heed the warnings, in an unprecedented breach of moral values, neglect of the precautionary principle, betrayal of trust and violation of the duty of care.

As a result, the IPCC persists with downplaying the potential for dangerous developments in efforts to hide the need for the most effective climate action. The IPCC keeps pointing at less effective policies such as support for BECCS and biofuel, while continuing to make it look as if there was a carbon budget to divide among polluters, as if polluters could continue to pollute for decades to come, as discussed in earlier posts such as this one.

Meanwhile, a 2018 study (by Strona & Bradshaw) indicates that most life on Earth will disappear with a 5°C rise. Humans, who depend for their survival on many other species, will likely go extinct with a 3°C rise, as illustrated by the image below, from an earlier post.

Climate Emergency Declaration

The situation is dire and the precautionary principle calls for rapid, comprehensive and effective action to reduce the damage and to improve the situation, as described in this 2022 post, where needed in combination with a Climate Emergency Declaration, as discussed at this group.

Links

• Climate Reanalyzer
https://climatereanalyzer.org

• The Scenario Model Intercomparison Project (ScenarioMIP) for CMIP6 - by Brian O'Neill et al. (2016)

https://gmd.copernicus.org/articles/9/3461/2016

• International Energy Agency (IEA) - CO2 Emissions in 2023 report
https://www.iea.org/reports/co2-emissions-in-2023

• September 2023, highest anomaly on record?

https://arctic-news.blogspot.com/2023/09/september-2023-highest-anomaly-on-record.html

• CO2 keeps accelerating
https://arctic-news.blogspot.com/2024/04/co2-keeps-accelerating.html

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

• Pre-industrial
https://arctic-news.blogspot.com/p/pre-industrial.html

• Clouds Feedback and the Clouds Tipping Point
https://arctic-news.blogspot.com/p/clouds-feedback.html

• The Threat
https://arctic-news.blogspot.com/p/threat.html

• Amplifying feedback loop between drought, soil desiccation cracking, and greenhouse gas emissions - by Farshid Vahedifard et al. 

https://iopscience.iop.org/article/10.1088/1748-9326/ad2c23
discussed on facebook at 
https://www.facebook.com/groups/arcticnews/posts/10161298567849679

• Size, distribution, and vulnerability of the global soil inorganic carbon - by Yuanyuan Huang et al. https://www.science.org/doi/10.1126/science.adi7918
discussed at facebook at 
https://www.facebook.com/groups/arcticnews/posts/10161354439024679

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

• When will humans go extinct? 
https://arctic-news.blogspot.com/2022/02/when-will-humans-go-extinct.html

• Shortcomings of IPCC AR6 WGIII - Mitigation of Climate Change
https://arctic-news.blogspot.com/2022/04/shortcomings-of-ipcc-ar6-wgiii-mitigation-of-climate-change.html

• Transforming Society

https://arctic-news.blogspot.com/2022/10/transforming-society.html

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

• Climate Emergency Declaration
https://arctic-news.blogspot.com/p/climate-emergency-declaration.html

UK MET Office keeps downplaying significance of events in the Arctic

One of the most respected datasets on Arctic sea ice volume is produced by the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS, Zhang and Rothrock, 2003) developed at the Polar Science Center, Applied Physics Laboratory, University of Washington. The graph below shows PIOMAS data for annual minimum Arctic sea ice volume (black dots) with an exponential trend added (in red).

The Arctic Methane Emergency Group (AMEG), in a February 12, 2012, written submission to the U.K.  Environmental Audit Committee (EAC), pointed at the graph:

. . summer volume [is] less than 30% of its value 20 years ago. The trend in volume is such that if one extrapolates the observed rate forward in time, by following an exponential trend line, one obtains a September near-disappearance of the ice by 2015.

The MET Office, in a March 8, 2012, written submission:

Climate models project the Arctic will become ice-free during summer at some point this century – though likely not before 2040. . . In September 2007, sea ice extent reached an all-time low, raising the question of whether the sea ice is likely to melt more quickly than has been projected. There is, however, no evidence to support claims that this represents an exponential acceleration in the decline. Indeed, modelling evidence suggests that Arctic sea ice loss would be broadly reversible if the underlying warming were reversed.

Professor Slingo, Chief Scientist, MET Office, elaborated on this in a March 14, 2012, oral submission:

Q114 Chair: . . when the Arctic will be ice free in summer. . . Professor Slingo: . . Our own model would say between 2040 and 2060 . . Q115 Chair: You would rule out an icefree summer by as early as 2015, for example? Professor Slingo: Yes we would . . . Q117 Chair: . . In terms of the modelling that you are using, does that cover . . . volume of ice? Professor Slingo: We run quite a sophisticated sea ice model. . . and we are looking forward now to the new measurements from CryoSat-2. Q118 Chair: . . evidence that we had suggested that the volume of ice had already declined by 75%, and that further decreases may cause an immediate collapse of ice cover. Professor Slingo: I wouldn’t [give credence to that]. We don’t know what the thickness of ice is across the whole Arctic with any confidence. . . I probably would [rule it out altogether] . . . to say we have lost 75% of the volume is inconsistent with our assessments.

Professor Laxon, director of Centre for Polar Observation and Modelling, where CryoSat-2 data is being analysed, in an August 24, 2012, written submission:

. . [analysis of] CryoSat-2 and ICESat data . . suggest a decrease in ice volume over the period 2003–12 at least as large as that simulated by PIOMAS, and possibly higher.

The Met Office, in an August 31, 2012, supplementary written submission:

The changes in observed sea-ice volume only extends [sic] over a few years and cannot in isolation be interpreted as representative of a long term trend. . . . The extrapolation of short-term trends in ice volume is not a reliable way to predict when the Arctic will be seasonally ice free as negative feedbacks and changing weather patterns may slow the rate of ice loss. . . it is worth noting that climate models can show a period of recovery in ice volume following periods of large ice volume loss.

For some curious reason, some people seek to downplay the significance of the events taking place in the Arctic, as well as the risk of methane releases. Here's more on that.

AMEG added, in its above February 12, 2012 written submission:

The catastrophic risk of global warming leading to very large emissions of methane from large Arctic carbon pools, especially from subsea methane hydrate, is documented in the 2007 IPCC assessment. By collaborating with others to protect the Arctic, a climate of cooperation can be engendered to protect the whole planet for the benefit of ourselves and future generations.

Professor Lenton, in a Feb 21, 2012, oral submission:

. . the Hadley Centre [has] permafrost in the latest state-of-the-art model . . . their best estimate is we may get 0.1°C of extra warming at the end of the century from the loss of methane from the northern high latitudes.

Professor Slingo, in the above March 14, 2012, oral submission:

Q126 Dr Whitehead:. . what sort of modelling factors may be accounted for by the possibility of tipping points or feedback attached to these? For example, the argument that follows very substantially from the extent of continental shelf that there is within the Arctic Basin and, therefore, the particular relationship that warming on that relatively shallow sea has on trapped methane-for example, the emergence of methane plumes in that continental shelf, apparently in quite an anomalous way-leading possibly to the idea that there may be either tipping points there or catastrophic feedback mechanisms there, which could then have other effects on things, such as more stabilised caps like the Greenland ice cap and so on. I rapidly collated all the possible catastrophe theories, but I mean how are those factored into the modelling process? Professor Slingo: . . we are not looking at catastrophic releases of methane. . . We don’t see catastrophic change in the Arctic that would lead to catastrophic releases of methane, or very large changes in the thermohaline circulation, within the next century. Our understanding of the various feedbacks-and it is a very complex system-both through observations and modelling, suggests that we won’t see those catastrophic changes, in terms of the physical system.

Note that the above are excerpts, to make things easier to read. For the full text, click on the respective links.

Below an update of the image, produced earlier this month, with recent volume data for 2012 added. On September 2, 2012, PIOMAS recorded a volume of 3407 cubic km of ice, i.e. very close to what the exponential line projected. The volume is likely to continue to fall further before reaching its final 2012 minimum.

The image below shows Arctic sea ice extent (total area of at least 15% ice concentration) for the last 7 years, compared to the average 1972-2011, as calculated by the Polar View team at the University of Bremen, Germany.