Crossing 1.5C - On track toward an uninhabitable Earth

by Andrew Glikson

“… but they can be sure that they won't be recorded for their crimes in history -- because there won't be any history” (Noam Chomsky, 2023)

The macabre criminality of world’s so-called leaders, coupled with the ignorant compliance of a majority of the victims of global heating and potential nuclear annihilation, belong to the inconceivable. It is not clear whether any climate scientists are left to whom governments are listening, for if they did, they would learn that the intensification of extreme weather events currently and later in the century is bound to render large parts of the planet uninhabitable. In particular of islands ravaged by cyclones and sea level rise, extensive tropical and subtropical coastal zones and lands subjected to storms, floods, draughts and fires, in Africa, Australia and India. Polar-sourced cold fronts crossing the weakening jet stream boundary are already disrupting North America, Siberia and Europe, as are warm air masses penetrating the Arctic circle.

Distracted by a series of horrific bloodsheds induced by toxic masculinity of alpha males around the world, propagated by the “media”, the multitudes are only dimly aware of the oncoming climate carnage, orders of magnitude bigger than currently forecast.

According to leading climate scientists like James Hansen and his colleagues: “Without major action to reduce emissions, global temperature is on track to rise by 2.5°C to 4.5°C by 2100” (NASA 2023). It is far from clear whether anything can be done to arrest or reverse global heating, for as temperatures rise so is the production of fossil fuels enhanced by science-ignorant hordes of politicians and economists oblivious to the basic laws of physics. Alternative clean energy without sharp cuts in fossil fuel combustion can hardly stem global heating.

[ Figure. 1. Daily surface temperature analysis from the ECMWF reanalysis version 5 (ERA5). ]

December was the 7th consecutive month of record-shattering global temperature (Figure 1.), driven by the combination of a moderately strong El Nino and a large decrease of Earth’s albedo. Hansen et al. (2024) expect record monthly temperatures to continue into mid-2024, due to the present large planetary energy imbalance, with the 12- month running-mean global temperature reaching +1.6-1.7°C relative to 1880-1920. It will be clear that the 1.5°C ceiling has been passed for all practical purposes, and that the mean global temperature is currently accelerating toward 2.0°C above pre-industrial temperature by the middle of the decade (Figure 2), while the Arctic has been warming nearly four times faster than the rest of the world over the last 43 years, on average around 3℃ warmer than it was in 1980. Over the past 30 years Antarctica has been one of the fastest-changing places on Earth, warming more than 3 times than the rest of the world.

[ Figure. 2. Global temperature relative to 1880-1920 based on the GISS analysis
(Goddard Institute of Space Studies) analysis - by James Hansen et al., 2024. ]

A projection by NOAA states: “While we cannot stop global warming overnight, we can slow the rate and limit the amount of global warming by reducing human emissions of heat-trapping gases and soot (“black carbon”). Unfortunately, this projection takes neither the amplifying feedback, i.e. from warming oceans, melting ice sheets, migrating climate zones and melting of methane, nor the time factor into account.

A factor rarely taken into account emerges from Hansen et al. (1996)'s paper “Ice melt, sea level rise and superstorms: evidence from paleoclimate data, climate modelling, and modern observations that 2°C global warming could be dangerous” (Figure 3). Here the flow of cold ice melt water results in formation of large cold-water pools of in the Atlantic and Southern oceans, inducing a contraction of the tropical climate zone and an overall decline in mean global temperatures. The collision between the cold air and water fronts and the tropical warm air mass would lead to severe storms over large tracts of Earth.

Likely transient respites in global warming (stadials) may take place over the next few centuries or longer, when the flow of cold ice-melt water from the Greenland and Antarctica ice sheets (Bronselaer et al., 2018; Glikson, 2019) reduces the mean rate of warming, although this may occur too late for civilization (Figure 3).

[ Figure 3. Surface air temperature (°C) relative to 1880-1920 for several scenarios - by James Hansen et al. 2016.
Future model transient cooling periods consequent on flow of ice meltwater from Greenland and Antarctica into oceans ]

The criminal insanity of political, military, strategic, economic leaders, matched by the blindness of billions, supports what has been referred to as Fermi’s Paradox ─ where the apparent absence of signals from technological civilizations in the Milky Way, may be explained in terms of a self-destruction of such civilizations.

Having ignored climate science, dismissed or fired climate scientists and repeatedly confected lies, while global heating accelerates with deleterious consequences, Homo “sapiens” is finding itself on track toward carbon poisoning of the atmosphere, the lungs of the inhabitable Earth, acidification of the hydrosphere and coating of the land with carbon and plastics.

A/Prof. Andrew Y Glikson
Earth and Paleo-climate scientist

Andrew Glikson

Books:

The Asteroid Impact Connection of Planetary Evolution
https://www.springer.com/gp/book/9789400763272
The Archaean: Geological and Geochemical Windows into the Early Earth
https://www.springer.com/gp/book/9783319079073
The Plutocene: Blueprints for a Post-Anthropocene Greenhouse Earth
https://www.springer.com/gp/book/9783319572369
The Event Horizon: Homo Prometheus and the Climate Catastrophe
https://www.springer.com/gp/book/9783030547332
Climate, Fire and Human Evolution: The Deep Time Dimensions of the Anthropocene
https://www.springer.com/gp/book/9783319225111
Evolution of the Atmosphere, Fire and the Anthropocene Climate Event Horizon
https://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
https://www.springer.com/us/book/9783319745442
The Fatal Species: From Warlike Primates to Planetary Mass Extinction
https://www.springer.com/gp/book/9783030754679
The Trials of Gaia. Milestones in the evolution of Earth with reference to the Antropocene
https://www.amazon.com.au/Trials-Gaia-Milestones-Evolution-Anthropocene/dp/3031237080