Downplaying the temperature rise from pre-industrial
Instead, when taking the 2020 temperature rise and going back one century, NASA data show a 1.29°C rise from 1920, and this is a conservative figure, as 0.1°C can be added to translate NASA's sea surface temperatures into ocean air temperatures and another 0.1°C can be added for higher polar anomalies, which brings the temperature rise up to almost 1.5°C and this isn't the full rise from pre-industrial by a long shot.
Furthermore, the IPCC uses seasonally-biased data to "reconstruct" the temperature rise that took place prior to its baseline, making it look as if there was no rise before its baseline.
Instead, the rise from pre-industrial to 1920 could be as much as 0.3°C (1750 to 1920) + 0.2°C (1520 to 1750) + 0.29°C (3480 BC to 1520).
|In February 2016, the temperature |
was 1.70°C higher than in 1900
(i.e. 1885-1914, the 30-year period
centered around the start of 1900)
The map on the right shows that the average global temperature was 1.70°C higher in February 2016 than around 1900 (i.e. 1885-1914). The map also shows local anomalies as high as 15.1°C and even higher peaks were reached on specific days.
|When building a bridge, an engineer will calculate how much load it can handle by first looking at how many heavy trucks will be using the bridge at times of PEAK traffic, rather than to average the weight of all vehicles on the bridge over a 30-year period. Caption and image by Sam Carana from earlier post.|
Downplaying the near-term temperature rise
Instead of pointing at the policies that can best be adopted, the IPCC uses Shared Socioeconomic Pathways (SSPs), and the only two scenarios for which the rise remains well below 2°C are SSP1-1.9 and SSP1-2.6 (images right).
So, have methane levels fallen since 2015?
Stronger methane releases from subsea permafrost can be expected, says a paper by Natalia Shakhova et al. A 1000-fold methane increase could occur, resulting in a rise of as much as 6°C within 80 years, with more to follow after that, according to a paper by Atsushi Obata et al.
Seafloor methane releases could be triggered by strong winds causing an influx of warm, salty water into the Arctic ocean (see this earlier post and this page). Since little hydroxyl is present in the atmosphere over the Arctic, it is much harder for this methane to get broken down.
Even relatively small methane releases could cause tremendous heating, if they reach the stratosphere. Methane rises from the Arctic Ocean concentrated in plumes, pushing away the aerosols and gases that slow down the rise of methane elsewhere, which enables methane erupting from the Arctic Ocean to rise straight up fast and reach the stratosphere. IPCC AR6 gives methane a lifetime of 11.8 years. IPCC TAR gave stratospheric methane a lifetime of 120 years, adding that less than 7% of methane did reach the stratosphere at the time.
|[ click on images to enlarge ]|
|[ from earlier post ]|
Such a high mean methane level by 2026 cannot be ruled out, given the rapid recent growth in mean annual methane levels and with double-digit growth sustained beyond 2020 to date. It is deceptive to assume that methane levels have fallen and will continue to fall, the more so since the IPCC doesn't point at the most effective policies to achieve reductions in methane emissions.
Even with less methane, when using a short horizon for the GWP of methane and adding the impact of further greenhouse gases (carbon dioxide, nitrous oxide, water vapor, etc.), the 1200 ppm CO₂e clouds tipping point could get crossed by 2026.
Natural variability acts as a catalyst in this case. Within a few years time, sunspots will be reaching the peak of their cycle, and they are looking stronger than forecast.
An upcoming El Niño could raise surface temperatures significantly. The image below indicates that the difference between the top of El Niño and the bottom of La Niña could be more than half a degree Celsius.
As illustrated by the bar on the right, there are many further elements that could dramatically push up the temperature soon. Altogether, the rise from pre-industrial could increase to more than 18°C by 2026.
|[ from the Quotes page ]|
“There is no carbon budget to divide between polluters, instead there is just a huge debt of CO₂ to be removed from the atmosphere and the oceans. Comprehensive and effective action must be taken to combat run-away warming.”
It should have been obvious by now that there is no “carbon budget”. Instead, there's only a huge and very dangerous carbon debt. There is no room for trade-offs or offsets, and terms such as negative emissions are simply inappropriate. All efforts should be made to cut emissions, including ending current subsidies for fossil fuel and livestock, while carbon could and should additionally be removed from the atmosphere and oceans. And even then, it's questionable whether any species, let alone humans, will be able to survive the coming decade, so additional action will need to be taken as well.
|[ see the extinction page ]|
The IPCC creates a perception that pollution could continue for decades to come, by downplaying the temperature rise and by downplaying the threat of a huge rise within years, while promoting the idea that there was a “carbon budget” to be divided among polluters that would enable polluters to keep polluting for decades to come. Again, the IPCC has failed to do what the Paris Agreement calls for, i.e. for the IPCC to specify the pathways that will give the world a better future, specifically the policies that are needed to facilitate a better future.
This IPCC report should be returned to be rewritten, to instead focus on the best policies to facilitate the necessary changes. The scientific evidence in favor of what needs to be done is overwhelming, from all kinds of perspectives, while it's also simply the right thing to do. Most effective are feebates, i.e. imposing fees on polluting products while using the revenues to support rebates on better alternatives, and feebates are especially effective when implemented locally. Studies on the effectiveness of feebates were made available as early as 2005 and feebates have been discussed by the IMF, the OECD and the UN, and have been implemented in various ways, e.g. in the Clean Car Programme in New Zealand. The situation is dire and calls for the most comprehensive and effective action, as described at the Climate Plan.
• IPCC special report on the impacts of global warming of 1.5 °C above pre-industrial levels and related global greenhouse gas emission pathways (SR1.5)
• Paris Agreement, adopted 2015
• Seasonal origin of the thermal maxima at the Holocene and the last interglacial - by Samantha Bova et al. (2021)
• Changing El Niño–Southern Oscillation in a warming climate - by Wenju Cai et al. https://www.nature.com/articles/s43017-021-00199-z
• IPCC report may have underplayed risk of freak El Nino and La Nina events
• IMF: Chapter 1. What Is the Best Policy Instrument for Reducing CO2 Emissions?, in: Fiscal Policy to Mitigate Climate Change - by Ruud de Mooij et al. (2012)
• How much warming have humans caused?
• A Temperature Rise Of More Than 18 Degrees Celsius By 2026?
• Could temperatures keep rising?
• Overshoot or Omnicide?
• Climate Plan
• Latent Heat
• Can we weather the Danger Zone?
• How much warmer is it now?
• When will we die?
• Most Important Message Ever
• Just do NOT tell them the monster exists
• 100% clean, renewable energy is cheaper
• Negative-CO2-emissions ocean thermal energy conversion
• 'Electrogeochemistry' captures carbon, produces fuel, offsets ocean acidification
• Olivine weathering to capture CO2 and counter climate change
• Biochar group at facebook
• IPCC seeks to downplay global warming
• Blue Ocean Event
• What Does Runaway Warming Look Like?
• Ten Dangers of Global Warming
• AGU poster, AGU Fall Meeting 2011