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Please cite this page as:
Chen, D. B (2016). Global 4C – Monetary Policy for Climate Change Mitigation.
Youtube videos cited in this webpage do not imply endorsement of Global 4C by the people in those videos or anybody associated with those videos.

Terrestrial Plants Reached ‘Peak Carbon’ 10 Years Ago (and Atmospheric CO2 Passes 400 ppm)

A recent study by Curran & Curran (2016) indicates that trees and plants may have reached ‘peak carbon’ absorption capacity in 2006; and for this reason the Earth’s terrestrial carbon sink appears to be weakening. This has been termed ‘peak carbon’ for land vegetation because, since about 2006, the carbon-appetite of land plants appears to have decreased. The amounts of carbon involved are enormous – comparable to the emissions of whole nations. A conclusion is that drastic actions are needed to wrestle global warming under control.

The Mauna Loa observatory shows that for the first time since mankind arrived on Earth, the atmospheric CO2 levels have passed 400 ppm all year round. We have entered into a new period of greenhouse gas driven climate change.


Climate models have underestimated Earth’s sensitivity to CO2 changes

Yale News, By Jim Shelton (April 7, 2016)

A Yale University study says global climate models have significantly underestimated how much the Earth’s surface temperature will rise if greenhouse gas emissions continue to increase as expected.

The Yale team’s estimate of climate sensitivity is much higher than that presented in 2013 by the Intergovernmental Panel on Climate Change (IPCC). Revised estimates of global warming could have dramatic implications for climate change policy, climate damages, and mitigation costs.

“It goes to everything from sea level rise to more frequent and extreme droughts and floods,” said Ivy Tan, a Yale graduate student and lead author of the study.


North American forests at high climate risk and adversely affected by clearing

Climate News Network, Tim Radford (March 6, 2016)

The warming effect on forests is most pronounced within between 20 and 100 metres of the forest’s edge, where temperatures can be as much as 8°C higher than deep in the forest interior. Professor Clark puts it more bluntly:

Our analysis shows virtually all US forests are now experiencing change and are vulnerable to future declines. Given the uncertainty in our understanding of how forest species and stands adapt to rapid change, it’s going to be difficult to anticipate the type of forests that will be here in 20 to 40 years.

Carbon dioxide causing ‘intoxication’ of ocean fish sooner than expected

Sydney Morning Herald
Future levels of carbon dioxide in the oceans could end up being higher than previously expected. The new research finds that fish in up to half the world’s surface oceans could suffer from behavioural impairment because of the rising carbon dioxide levels. The study is based on a global database of seawater carbon dioxide concentrations from the past 30 years and projections for 2100. The Ellen MacArthur Foundation also reported that the world’s oceans may contain more plastics than fish (by weight) by 2050.

Essentially, the fish become lost at sea

Ben McNeil, of UNSW.

Democracy Now! – Kevin Anderson (Deputy Director, Tyndall Centre for Climate Research)

Anderson comments on the COP21 meeting in Paris, and explains why the risks are generally greater than indicated in the mainstream narrative on climate science and economics.


Guardian – Ian Sample (Science editor)

Collapsing Greenland glacier could raise sea levels by half a metre, say scientists

See: Huge Zachariae Isstrom glacier has begun to break up, starting a rapid retreat that could continue to raise sea levels for decades to come.

See: Newly Discovered Greenland Melting Could Accelerate Sea-Level Rise at New Scientist.


John Church, Chris Roberts, Axel Timmerman, Michael Mann, Byron Steinman, Sonya Miller, et al.

Consider yourself warned. We can expect a burst of supercharged warming when the pause in rising global temperatures finally ends.

See: A major surge in ocean warming may be coming in the next five years at Motherboard.

See: Burst of warming may end lull in rising temperatures at New Scientist.


Johan Rockström

 “we as humanity are now in a position to disrupt the stability of the entire world system” by driving climate change. … “we need a new relationship between people and the planet”.

see Reuters

Understanding and Addressing Infinite and Existential Climate Risks | Stockholm Resilience Center, Stockholm university, Stockholm, Sweden |

“Scientific evidence indicates humanity has entered a new geological epoch, the Anthropocene, where the world entreprise constitutes the largest driver of change at the planetary scale. Furthermore, we increasingly find evidence that the social and environmental response to rising human pressures on the planet are non-linear, and that the globalized world of the 21st century is associated with rising social-ecological turbulence. This raises the need to better understand risks of facing infinite or existential risks, i.e., risks that may affect a significant proportion of the global population or the entire world community…”

see International Scientific Conference (7-10 July 2015) Paris, France

Prof. Peter Wadhams

Cambridge University May 2015

Prof. Wadhams discusses the status of sea ice and likelihood of abrupt climate change in the Arctic region. The implications of an ice-free summer includes methane release from the ocean floor and permafrost. Prof. Wadhams estimates that the chances of runaway warming in the Arctic at about 50%. This would imply that there is a 50% chance that our civilisation will be undermined by methane-driven global warming this century.

Prof. Hans Joachim Schellnhuber

Stockholm Food Forum 2015 | EAT

Peter Sherwood

“4C would likely be catastrophic rather than simply dangerous.”

Peter Sherwood referring to potential temperature rise by 2100

(The Guardian, 2013).


“Global average temperatures will rise at least 4 degrees Celsius by 2100 and potentially more than 8 degrees C by 2200 if carbon dioxide emissions are not reduced,..”

Article in the Science Daily based on an interview with Peter Sherwood (Science Daily, 2013)


See Journal Paper and a discussion paper is found here.

Steven C. Sherwood, Sandrine Bony, Jean-Louis Dufresne. Spread in model climate sensitivity traced to atmospheric convective mixing. Nature, 2014; 505 (7481): 37 DOI: 10.1038/nature12829


The Apollo-Gaia Project

In this video,David Wasdell gives his summary of concerns and issues regarding the IPCC’s current presentation and application of the Earth’s short-term climate sensitivity and the assumed carbon budget to avoid 2 degrees Celsius warming.

David Wasdell discusses the Charney Sensitivity or Equilibrium Climate Sensitivity which is a transient sensitivity used by the IPCC, and the long-term Earth System Sensitivity which defines the long-term surface temperature over a period of centuries or millennia.

Recorded Video Conference


Long-term decline of the Amazon carbon sink

by Brienen et al (2015).

“The amount of carbon the Amazon’s remaining trees removed from the atmosphere fell by almost a third last decade, leading scientists to warn that manmade carbon emissions would need to be cut more deeply to tackle climate change.

Trees in untouched areas of the forest have been dying off across the basin at an increasing rate, found the study, published in Nature on Wednesday. Meanwhile the tree growth produced by higher CO2 levels in recent decades levelled off.”

The Guardian Article

see Journal Paper

Nature 519, 344–348 (19 March 2015) doi:10.1038/nature14283
Received 09 April 2014 Accepted 04 February 2015 Published online 18 March 2015


Climate Sensitivity Somewhere Between 2 and 3.2 degrees-C, But….

see Article at Carbon Brief

Knutti tells Carbon Brief:

Those [energy balance] methods assume that the feedbacks in the present day are the same as those in the future“.

There’s evidence that feedbacks depend on the climate state and increase in strength as we go towards higher temperatures, Knutti explains, with the result that climate sensitivity inferred from the observed warming is very likely too low. He says:

If existing feedbacks change because the climate changes, or if new feedbacks like permafrost or methane hydrates become relevant, then that would not be captured by this method.”

Prof. Reto Knutti –


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