Is humanity dying? Christian Mihatsch, Climate reporter, June 9, 2019.
The climate crisis is becoming increasingly apocalyptic. It is unlikely that our civilization will end soon — but possible. And this possibility is still receiving too little attention.
The perception of the climate problem is currently changing rapidly. The term "climate change" is increasingly being replaced by "climate crisis", and instead of "warming", what will probably prevail is "climate overheating" or a similar term. But is it appropriate to speak of the end of our civilization or even the extinction of humanity?
Some of the most important climate movements are doing just that. Extinction Rebellion is already carrying extinction in its name and the movement's first call is: Tell the truth and explain the state of emergency.
Fridays for Future's Greta Thunberg also clearly states what options humanity has: "Either we choose to preserve our civilization or we do not." And addressing world leaders, Thunberg says: "I want you to panic."
But is there really a reason to panic? The IPCC says that overheating can theoretically be stopped at 1.5 degrees. The IPCC reports are considered the "gold standard" of climate science because they summarize the findings of thousands of studies.
But the reports are also criticized, for example, because of their language. Prof. Hans Joachim Schellnhuber, ex-head of the Potsdam Institute for Climate Impact Research and an IPCC author, says that among IPCC authors a trend has developed "to err on the side of least drama". So you may present a better situation than exists in order not to sound alarmist.
The “probability obsession" of the IPCC
In addition, the IPCC assumes that warming will continue in a linear fashion. However, many climate models show that warming is accelerating. The difference: Instead of 2040, the 1.5-degree threshold will be reached in 2030 (see diagram).
In addition, the IPCC does not take into account feedback processes such as permafrost thawing, whichmay [will] cause climate overheating to increase.
According to Schellnhuber, however, the biggest drawback is the IPCC's "probability obsession" because it means not enough attention is paid to the most dangerous developments: "Calculating probabilities has little meaning in the most critical areas, such as the thawing of permafrost or the possible collapse of entire states."
In addition, the damage of, for example, the collapse of our civilization cannot be quantified. A recent study by the Australian think tank Breakthrough states: "A risk is usually calculated by multiplying the probability of an event by the expected damage, but if the damage can no longer be quantified, this method breaks down."
But even in the quantifiable realm, one underestimates the risk by focusing on relatively probable warming and masking worst-case scenarios. For these damages increase exponentially (see chart below).
Unlikely, but catastrophic
Schellnhuber calls for less attention be paid to "probabilities" and more to "possibilities". "This corresponds to the scenario planning in the economy, where the consequences of possible developments are examined, which seem unlikely, but have far-reaching consequences."
That's exactly what the authors of the Breakthrough study, David Spratt and Ian Dunlop, have done, developing a scenario that will raise the climate by three degrees by 2050. That's not extreme. For the 30 years to the middle of the century, there is a five percent chance that the climate will warm up by 3.5 to 4 degrees.
How sensitive is the climate to the warming of the atmosphere
(climate sensitivity) and what are the consequences?
The probability (likelihood) multiplied by the damage (impact)
gives the risk (risk). The light blue bar shows that very
unlikely developments are the biggest risk.
(Graphic from the study).
To show how this can happen, Spratt and Dunlop tell a "story": In the coming decade, the climate crisis is still receiving too little attention, and emissions will continue to rise until 2030, only to decline thereafter. Then it is already too late and the climate warms by 2050 by three degrees.
In retrospect, scientists then find that several tipping points have been reached, such as the thawing of permafrost and droughts in the Amazon rainforest. One-third of the earth is now too hot for at least 20 days a year to allow people to survive outdoors. Food production is no longer enough to feed all people, and there are more than a billion climate refugees.
As I said: The probability of this development is around five percent.
The climate crisis is becoming increasingly apocalyptic. It is unlikely that our civilization will end soon — but possible. And this possibility is still receiving too little attention.
The perception of the climate problem is currently changing rapidly. The term "climate change" is increasingly being replaced by "climate crisis", and instead of "warming", what will probably prevail is "climate overheating" or a similar term. But is it appropriate to speak of the end of our civilization or even the extinction of humanity?
Some of the most important climate movements are doing just that. Extinction Rebellion is already carrying extinction in its name and the movement's first call is: Tell the truth and explain the state of emergency.
Fridays for Future's Greta Thunberg also clearly states what options humanity has: "Either we choose to preserve our civilization or we do not." And addressing world leaders, Thunberg says: "I want you to panic."
But is there really a reason to panic? The IPCC says that overheating can theoretically be stopped at 1.5 degrees. The IPCC reports are considered the "gold standard" of climate science because they summarize the findings of thousands of studies.
But the reports are also criticized, for example, because of their language. Prof. Hans Joachim Schellnhuber, ex-head of the Potsdam Institute for Climate Impact Research and an IPCC author, says that among IPCC authors a trend has developed "to err on the side of least drama". So you may present a better situation than exists in order not to sound alarmist.
The “probability obsession" of the IPCC
In addition, the IPCC assumes that warming will continue in a linear fashion. However, many climate models show that warming is accelerating. The difference: Instead of 2040, the 1.5-degree threshold will be reached in 2030 (see diagram).
In addition, the IPCC does not take into account feedback processes such as permafrost thawing, which
According to Schellnhuber, however, the biggest drawback is the IPCC's "probability obsession" because it means not enough attention is paid to the most dangerous developments: "Calculating probabilities has little meaning in the most critical areas, such as the thawing of permafrost or the possible collapse of entire states."
In addition, the damage of, for example, the collapse of our civilization cannot be quantified. A recent study by the Australian think tank Breakthrough states: "A risk is usually calculated by multiplying the probability of an event by the expected damage, but if the damage can no longer be quantified, this method breaks down."
But even in the quantifiable realm, one underestimates the risk by focusing on relatively probable warming and masking worst-case scenarios. For these damages increase exponentially (see chart below).
Unlikely, but catastrophic
Schellnhuber calls for less attention be paid to "probabilities" and more to "possibilities". "This corresponds to the scenario planning in the economy, where the consequences of possible developments are examined, which seem unlikely, but have far-reaching consequences."
That's exactly what the authors of the Breakthrough study, David Spratt and Ian Dunlop, have done, developing a scenario that will raise the climate by three degrees by 2050. That's not extreme. For the 30 years to the middle of the century, there is a five percent chance that the climate will warm up by 3.5 to 4 degrees.
(climate sensitivity) and what are the consequences?
The probability (likelihood) multiplied by the damage (impact)
gives the risk (risk). The light blue bar shows that very
unlikely developments are the biggest risk.
(Graphic from the study).
To show how this can happen, Spratt and Dunlop tell a "story": In the coming decade, the climate crisis is still receiving too little attention, and emissions will continue to rise until 2030, only to decline thereafter. Then it is already too late and the climate warms by 2050 by three degrees.
In retrospect, scientists then find that several tipping points have been reached, such as the thawing of permafrost and droughts in the Amazon rainforest. One-third of the earth is now too hot for at least 20 days a year to allow people to survive outdoors. Food production is no longer enough to feed all people, and there are more than a billion climate refugees.
As I said: The probability of this development is around five percent.
[MW: nope: its higher... this estimate of probability is based on the IPCC stuff, which, as mentioned above, is plagued by "conservatism" and "scientific reticence"... how can you properly calculate the probabilities if you ignore the positive feedback effects that you can't include in your models because you don't understand them well enough yet?! next gen climate models are increasingly showing that ECS, or earth climate sensitivity, is higher than previously assumed. see the Ian Welsh article posted June 16 about everything happening faster, in a bad way, than scientific consensus said it would. UN is always too optimistic (in the same way the consensus of economists always is)]
Extinction Rebellion and Greta Thunberg invoke such scenarios with their apocalyptic language. Still, it is more likely that our civilization will not end and humanity will not die out.
Extinction Rebellion and Greta Thunberg invoke such scenarios with their apocalyptic language. Still, it is more likely that our civilization will not end and humanity will not die out.
[says you, and your optimism bias, i.e. wishful thinking not based on facts... but under business as usual, we are f'd; and even if we transform everything NOW (As Naomi Klein says, This Changes Everything), it may still be too late due to tipping points, in particular methane release from permafrost and seafloor]
Nevertheless, it is possible if our protection from climate change continues to be only half-hearted.
These "possibilities" must be given more attention, says Schellnhuber: "This is especially true when it comes to the survival of our civilization."
These "possibilities" must be given more attention, says Schellnhuber: "This is especially true when it comes to the survival of our civilization."
Existential climate-related security risk. David Spratt and Ian Dunlop, Breakthrough Institute.
A scenario approach
Understanding climate-driven security risks relies on climate impact projections, but much knowledge produced for policymakers is too conservative. Because the risks are now existential, a new approach to climate and security risk assessment is required using scenario analysis.
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