Showing posts with label existential. Show all posts
Showing posts with label existential. Show all posts

Friday, September 24, 2021

The dilemma of climate scientists

by Andrew Glikson

“in private conversations, many climate scientists express far greater concern at the progression
of global warming and its consequences than they do in public” - Andrew Glikson (2016)

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

A climate chain reaction is believed to have pertained about 55 million years ago (Paleocene-Eocene Thermal Maximum [PETM]).

During the Anthropocene (post-1750 and in particular post-1900) greenhouse gas and temperature growth rates levels exceeded those of the PETM and of the end of the last glacial termination (LGT). During 2010-2020 an acceleration of global warming is reflected by an anomalous rise in greenhouse gas levels and temperatures (Figure 1).
Figure 1. 1880-2020 temperature anomalies relative to the 1951-1980 base line (NASA, NOAA, Hadley, Berkeley)

According to Peter Ward and others early examples of mass extinctions triggered by biological processes were related to ocean anoxia and acidification leading to CH4 and H2S release by “purple” and “green” algae and sulphur bacteria. Likewise, anthropogenic global warming constitutes a geological/biological process for which the originating organisms (humans) have not to date been able to discover an effective method of control.

The critical criterion definitive of global warming is the atmospheric concentration of greenhouse gases, rising from 280 to 419 ppm, i.e. by about 49% since pre-industrial time, only rarely mentioned by the media and politicians. Other parameters of climate change, such as the level of methane and nitrous oxide, have risen about 3-fold. While opinions by journalists, politicians, economists and social scientists proliferate, less attention is given to what is indicated by climate science, rendering the global response to the looming calamity increasingly irrelevant.

Thus, whereas most models portray linear rise in temperature, the evidence for the breading of the circum-Arctic jet stream, allowing cold and warm fronts to cross the boundary, would result in high storminess in high latitudes.

“Most scientists agree that climate change is happening faster than predicted. More than one-third of the world’s soil, which produces 95% of the world’s food supply, is currently degraded. By 2035, outdoor air pollution is projected to be a top cause of environmentally-related deaths worldwide, and half the world’s population will face water shortages.” However, many scientists are reluctant to warn the public about the full consequences of accelerating global heating. Namely, as Joachim Schellnhuber, Germany’s chief climate scientist has stated, the existential risk to the life support systems of the planet.

There is a heavy price to pay for communicating distressing evidence, Cassandra-like, including psychological factors and/or social and professional isolation. Personal optimism may overcome realism. Some scientists are either self-censored or have their work suppressed or dismissed within institutions or by the media, including in government and academia. Some scientists have lost their position.

As cited in the article titled “When the End of Human Civilization Is Your Day Job“ … “Among many climate scientists, gloom has set in. Things are worse than we think, but they can't really talk about it”, and elsewhere “in private conversations, many climate scientists express far greater concern at the progression of global warming and its consequences than they do in public”. It is not uncommon to hear people criticizing climate scientists for not telling them more about the future climate, although when they are told, many recoil. Then there is the plethora of false promises by politicians.

As the world continues to spend $trillions each year on military preparation for war or nuclear war, resources needed if serious attempts are made for protection of life on Earth, despair sinks in.

But the world is now waking up to the climate calamity.

There must be hope.

Andrew Glikson
A/Prof. Andrew Glikson

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

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
Climate, Fire and Human Evolution: The Deep Time Dimensions of the Anthropocene
https://www.springer.com/gp/book/9783319225111
The Plutocene: Blueprints for a Post-Anthropocene Greenhouse Earth
https://www.springer.com/gp/book/9783319572369
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 Event Horizon: Homo Prometheus and the Climate Catastrophe
https://www.springer.com/gp/book/9783030547332
The Fatal Species: From Warlike Primates to Planetary Mass Extinction
https://www.springer.com/gp/book/9783030754679




Wednesday, September 4, 2013

Existential risks to our planetary life-support systems

By Andrew Glikson

Figure 1. The future of Earth’s living environment is a non-issue in the current
Australian election - NASA image: Earth rising over the Moon
“We’re simply talking about the very life support system of this planet.”– Hans Joachim Schellnhuber, chief climate advisor to the German Government
It is not news that we are over stretching our planetary support systems: we have known for some time. In a 2009 keynote paper in Nature titled “A safe operating space for humanity”, a group of 26 prominent scientists showed three of nine interlinked planetary boundaries – boundaries we must stay within to keep Earth safe – have already been overstepped (see figure 2. below).

Those boundaries include:
  • climate change
  • biodiversity loss
  • the biogeochemical cycles.

Kevin Trenberth, chief scientist of the National Center for Atmospheric Research in Boulder, Colorado, states:
“Some of the human-induced changes are occurring 100-times faster than they occur in nature … And this is one of the things that worries me more than climate change itself. It’s actually the rate of change that’s most worrying … Ecosystems are not prepared for this jolt … And neither are many human endeavours, built around assumptions about how hot it’s going to be, how much it’s going to rain on our croplands, and how high the seas will rise.”

Figure 2. Planetary boundaries - the colored star-like area represents the estimated current state and the corners of the red octagon circumscribed by the Earth are the estimated boundaries. Systems whose safe operating space could not yet be determined were left out. Image from: Wikipedia / A safe operating space for humanity, Rockström et al, 2009.

This observation is dramatically demonstrated by the current rise of atmospheric greenhouse gases: this is at an unprecedented rate of 2 to 3 parts per million per year (see figure 3. below). This renders our era – the Anthropocene – a major oxidation event.

Such a growth rate of atmospheric greenhouse gases is extremely rare in geological history. The only analogue is the excavation of billions of tons of carbon from carbonate and shale formation hit by asteroids, such as the K-T impact 65 million years ago and massive global volcanic eruptions.

The consequences for the biosphere – the sixth mass extinction of species – threatens to become a tragedy for human ideals and for nature.

What or who is responsible for the unfolding calamity?

As defined, the Anthropocene is a new geological era triggered by a species which has uniquely mastered ignition. We are using it to excavate and release hundreds of billions of tons of carbon accumulated in Earth’s crust over geological eras into atmosphere.

Once a species masters sources of energy larger by orders of magnitude than its own physiological process (for Homo Sapiens this has been fire, electricity and nuclear fission), the species can hardly be expected to have the wisdom and degree of responsibility to stop its inventions from getting out of control.

Figure 3. Estimates of fossil fuel resources and equivalent atmospheric CO2 levels, including (1) emissions to date;
(2) estimated reserves, and (3) recoverable resources (1 ppm CO2 ~ 2.12 GtC). 
Hansen, 2012, figure 1; http://www.columbia.edu/~jeh1/mailings/2012/20120127_CowardsPart1.pdf
Unique among all species, humans adopted fire and combustion as their source of energy and power over nature. Over the last two million years, camped around fires, watching the flames, human imagination has grown to inquire, perceive future possibilities, develop fears, the craving for immortality, and the concept of gods. Fire has imparted a mythological quality to the human mind.

Once a stable climate was established in the Holocene (about 10,000 years ago), allowing cultivation and production of surplus food, this craving for omnipotence and omniscience was expressed by the building of monuments to immortality, the pyramids, as well as endless wars acquiring loot for this purpose.

Spiritual pantheism by pre-historic people such as the Australian Aboriginals has been transformed into admiration of sky gods and monotheism, then into crass materialism and the space cult.

But space exploration has taught us no other planet exists in the solar system on which the conditions exist for advanced life of the type hosted by Earth.

Since the greenhouse effect and its underlying laws of physics and chemistry were decoded in the 19th century, the question has arisen: to what extent will societies and their leaders accept the implications of the science for human industry and human future? Will the scientific method itself and the enlightenment form the basis of future decisions?

In 21st century Australia, the answer has been a resounding “no”.

Government and corporate decisions on climate change are being influenced by misrepresentations of the evidence. What began some 20 years ago as demonstration of solid empirical evidence has deteriorated to media-controlled debate replete with misunderstandings of the basic laws of physics, paleo-climate science, climate science, biological and ecological principles.

Figure 4. Relations between CO2 rise rates and mean global temperature rise rates during warming periods,
including the Paleocene-Eocene Thermal Maximum, Oligocene, Miocene, late Pliocene, Eemian (glacial termination),
Dansgaard-Oeschger cycles, Medieval Warming Period, 1750-2012 and 1975-2012 periods.
A multitude of media outlets and hundreds of websites proliferate notions ignorant of peer-reviewed science. The lesson of numerous attempted debates with those who deny the reality of global warming, or attempt to attribute it to natural non-human factors, is that those entertaining these notions cannot be dissuaded by any amount of scientific evidence.

Climate change misconceptions include claims that:
  • temperature rise came before CO2 rise during the glacial terminations and that therefore the current rise of temperature is not the result of CO2 rise. However, the effects of CO2and temperature variations are intertwined. During the last ~400,000 years glacial eras were terminated by periods of intense solar activity, affecting decreased CO2 solubility in warming water and thereby a rise in CO2 levels of the atmosphere. By contrast climate developments since the 18th century, when there was negligible or no rise in solar energy hitting the earth, were triggered by the anthropogenic greenhouse effect of the release of 560 billion tonnes of carbon, consistent with the basic laws of physics.
  • global warming is a recovery from the Little Ice Age. However, the Little Ice Age was caused when sunspot activity nearly ceased between 1650 and 1700, depressing global temperatures by 0.2-0.3C relative to preceding periods. By contrast, global warming from about 1975 has tracked toward more than 1.5C over the continents relative to pre-industrial temperatures.
  • cosmic rays flux affects warming. However, a dominant solar effect on the climate since 1970 is ruled out by measurements of solar radiation. The incidence of cosmic rays, which oscillate reciprocally with the 11 years sunspot cycle, has been shown to have minor effects on cloud nucleation and has not varied significantly since the mid-20th century.
  • carbon dioxide is emitted mainly from volcanoes. However, according to the United States Geological Survey (2012), sub-aerial and sub-marine volcanism emits approximately 150–260 million tons of CO2 a year. Anthropogenic emissions total about 35 billion tons CO2 a year.
Meanwhile, the unthinkable consequences of 4 degrees Celsius and higher temperature rise on the terrestrial atmosphere-ocean system have already begun. We are seeing a series of extreme weather events, reflecting the rise in energy/temperature of the atmosphere-ocean system – the “new normal”.

Andrew Glikson
Does responsibility lie with vested interests and fossil fuel lobbies promoting carbon saturation of the atmosphere? Does it lie with media barons and their mouthpieces hijacking the information systems of democracies, or with cowardly political “leaders” – presiding over extensive demise of future generations? Or does responsibility lie with all of us, with the species?

Deceived by pseudoscientific misconceptions, Homo “sapiens” continues to march toward a cliff, taking much of nature with it.

Earlier published at The Conversation.