5
degradation are already underway, a phenomenon which could lead to release of
dangerous amounts of methane and CO 2 . This paper also concluded that carbon
emissions from melting permafrost could increase soil carbon emissions by
125–190% compared to gradual thaw alone. This paper also concluded that models
used to predict climate impacts have failed to incorporate abrupt carbon feedbacks
from permafrost decay that recent evidence has revealed is now possible. Carbon
emissions from melting permafrost could increase soil carbon emissions by
125–190% compared to gradual thaw alone.
Another paper published on May 20, 2019 in the Proceedings of the National
Academy of Sciences, “Ice sheet contributions to future sea-level rise from structured expert judgment” (Bamber et al. 2019), concluded that sea level rise could be
2 m by 2100, double the amount predicted by IPCC in its Fifth Assessment Report.
Another paper published in February 2019 in the Journal of Biogeochemical
Cycles, “Very Strong Atmospheric Methane Growth in the 4 Years 2014–2017,”
(Nesbit et al. 2019) warned of greater than expected atmospheric methane levels.
This paper claimed that the rise in atmospheric methane (CH4), which began in
2007, had accelerated in the past 4 years. This growth has been worldwide, especially in the tropics and northern midlatitudes. With the rise has come a shift in the
carbon isotope ratio of the methane. According to this paper, methane’s increase
since 2007 was not expected in future greenhouse gas scenarios compliant with the
targets of the Paris Agreement, and if the increase continues at the same rates it may
become very difficult to meet the Paris goals.
2 Why Is IPCC Underestimating Climate Impacts?
Another paper, “What Lies Beneath: On the Understatement of Existential Climate
Risk” (hereinafter “WLB” 2018) by D. Sprat & I. Dunlap and published by the
Breakthrough Institute, claims both that the risks posed by climate change are far
greater than is evident from the conclusions of IPCC and examines why IPCC has
frequently underestimated threats from climate change.
The WLB report further concludes that climate change is now an existential risk
to humanity, that is an adverse outcome that could either annihilate intelligent life
or permanently and dramatically curtail its potential (WLB 2018, p. 13).
Although the WLB report acknowledges IPCC has done “critical, indispensable
work of the highest standard in pulling together a periodic consensus of what must
be the most exhaustive scientific investigation in world history” however, WLB
claims that the IPCC process suffers from all of the dangers of consensus-building
in such a wide-ranging and complex arena (WLB 2018, p. 5). That is, the report
attributes the overly conservative conclusions of the IPCC to the consensus nature
that IPCC must follow to get governments to approve IPCC final reports and the
pressure that some governments would place on IPCC if some conclusions were not
based on scientifically rigorous evidence.
Lessons Learned from IPCC’s Underestimation of Climate Change Impacts…
degradation are already underway, a phenomenon which could lead to release of
dangerous amounts of methane and CO 2 . This paper also concluded that carbon
emissions from melting permafrost could increase soil carbon emissions by
125–190% compared to gradual thaw alone. This paper also concluded that models
used to predict climate impacts have failed to incorporate abrupt carbon feedbacks
from permafrost decay that recent evidence has revealed is now possible. Carbon
emissions from melting permafrost could increase soil carbon emissions by
125–190% compared to gradual thaw alone.
Another paper published on May 20, 2019 in the Proceedings of the National
Academy of Sciences, “Ice sheet contributions to future sea-level rise from structured expert judgment” (Bamber et al. 2019), concluded that sea level rise could be
2 m by 2100, double the amount predicted by IPCC in its Fifth Assessment Report.
Another paper published in February 2019 in the Journal of Biogeochemical
Cycles, “Very Strong Atmospheric Methane Growth in the 4 Years 2014–2017,”
(Nesbit et al. 2019) warned of greater than expected atmospheric methane levels.
This paper claimed that the rise in atmospheric methane (CH4), which began in
2007, had accelerated in the past 4 years. This growth has been worldwide, especially in the tropics and northern midlatitudes. With the rise has come a shift in the
carbon isotope ratio of the methane. According to this paper, methane’s increase
since 2007 was not expected in future greenhouse gas scenarios compliant with the
targets of the Paris Agreement, and if the increase continues at the same rates it may
become very difficult to meet the Paris goals.
2 Why Is IPCC Underestimating Climate Impacts?
Another paper, “What Lies Beneath: On the Understatement of Existential Climate
Risk” (hereinafter “WLB” 2018) by D. Sprat & I. Dunlap and published by the
Breakthrough Institute, claims both that the risks posed by climate change are far
greater than is evident from the conclusions of IPCC and examines why IPCC has
frequently underestimated threats from climate change.
The WLB report further concludes that climate change is now an existential risk
to humanity, that is an adverse outcome that could either annihilate intelligent life
or permanently and dramatically curtail its potential (WLB 2018, p. 13).
Although the WLB report acknowledges IPCC has done “critical, indispensable
work of the highest standard in pulling together a periodic consensus of what must
be the most exhaustive scientific investigation in world history” however, WLB
claims that the IPCC process suffers from all of the dangers of consensus-building
in such a wide-ranging and complex arena (WLB 2018, p. 5). That is, the report
attributes the overly conservative conclusions of the IPCC to the consensus nature
that IPCC must follow to get governments to approve IPCC final reports and the
pressure that some governments would place on IPCC if some conclusions were not
based on scientifically rigorous evidence.
Lessons Learned from IPCC’s Underestimation of Climate Change Impacts…