Our approach to climate analysis places
highest priority on data. Climate forcing (see the definition at the end
of this communication) by GHGs is a good place to start, as it is the
drive for global warming. GHG amounts are well-measured. Our calculated
forcings are in close agreement[2] with those of IPCC and we also agree
with IPCC that the uncertainty in absolute GHG forcing is about
10%.[3] We show the 60-month (5-year) running-mean of GHG forcing change
(Fig. 1) to smooth out short-term variability of sources and sinks of
the gases. Thus, results for the last 2.5 years are shaded, because they
are <60-month means and will therefore change as more data are
added, likely decreasing the current peak value a bit. [HGs are 45
halogenated gases, including the HGs covered by the Montreal Protocol
and other HGs.]
One implication of the increased growth rate of GHG forcing in the last
15 years is that the goal to keep global warming under 2°C is now
implausible. IPCC defined a GHG scenario (RCP2.6) intended to provide a
66% chance of keeping global warming below 2°C. Actual growth of GHG
forcing has diverged dramatically from that scenario (Fig. 1), with
reality being close to the extreme RCP8.5 scenario. The gap between
reality and RCP2.6 could be closed by capturing and storing CO2 (carbon capture and sequestration, CCS), but the annual
cost for the gap at January 2023 (the time of the last 60-month mean)
would be $2.4-5 trillion[4] with current technology, and the gap and
annual cost are increasing.
RCP2.6, in fact, was never plausible, as it relied on assumption of
large-scale biomass-burning at powerplants with carbon capture and
permanent storage of the captured CO2, a scheme that would
ravage nature and threaten food security.[5] We scientists must share
the blame, if we allow policymakers to believe that such scenarios
provide a realistic projection of climate change.
Missed opportunities
to phase down the growth of GHGs are worth understanding because that
knowledge can aid development of future policies. Useful information on
climate change and energy policy was already available in 1988, when
IPCC was formed. Global reserves of conventional fossil fuels (coal,
oil, gas) clearly were enough to cause climate change, albeit of
uncertain magnitude. The science community had been asked, at least
implicitly, if it made sense to develop unconventional fossil fuels to
succeed coal, oil, and gas as a major source of world energy. The famous
Charney report[6] on climate change was requested by the Science
Adviser of U.S. President Jimmy Carter because of concern about
potential climate effects of Carter’s plans for coal gasification and
the fossil fuel industry’s budding efforts in hydrofracturing of rock
formations (fracking) to extract “tight” oil and gas. In subsequent
decades, scientific concern about the threat of human-caused climate
change grew continually.
Given a desire to limit fossil fuel emissions, economics recognizes
superiority of honest pricing as the efficient means to achieve change,
as opposed to arbitrary political dictates. The price of fossil fuels
should include their costs to society, which implies the merit of a
slowly rising carbon fee to achieve competition among clean energies,
energy efficiency, and carbon capture. Instead, the 1997 Kyoto Protocol
and 2015 Paris Agreement are precatory (wishful thinking) agreements to
try to reduce future emissions. The Paris meeting was preceded by
substantial effort to inform the delegates about the need for a simple,
honest, rising, carbon fee, but the response of the Executive Secretary
of the United Nations Framework Convention on Climate Change dismissed
this with “(Many have said) we need a carbon price and (investment)
would be so much easier with a carbon price, but life is more complex
than that.”[7] In fact, a carbon price is the simple approach; it only
requires agreement of the nations with largest emissions; it can be made
near-global by border duties on products from nations without a carbon
price. The reason a global carbon price does not exist is that
governments are under the corrupting thumb of special interests and give
little weight to the interests of young people and future generations.
A second missed opportunity, although less fundamental than the failure
to promote a carbon fee or tax, is egregious because it was
self-inflicted by the COP (Conference of the Parties) process. In 2001
at COP 6-2 in Bonn, Germany used its position as host nation to push
through exclusion of nuclear power from support as a Clean Development
Mechanism (CDM). Indeed, failure to support development of nuclear power
as a carbon-free source of energy was widespread. In President Bill
Clinton’s first State-of-the-Union speech after the 1992 United States
election, he announced that research and development of nuclear power
was unnecessary and would be terminated. Almost unlimited subsidy of
renewable energies was adopted in many U.S. states and some other
nations via “Renewable Portfolio Standards,” requiring utilities to
obtain a growing fraction of their energy from renewable energies. This
approach, as contrasted with “Clean Energy Portfolio Standards,” spurred
the development of natural gas as the complement to intermittent
renewable energy, and, as a consequence, expansion of fracking,
pipelines, and methane leakage. Nuclear power, given the costs of the
fuel and materials to build a power plant, has potential to be the least
expensive among the firm, dispatchable, energy sources, but attainment
of its potential, as with other sources, requires extensive R&D and
experience. Thus, it is ironic that the COP now suddenly asks for
nuclear energy output to be tripled.[8]
How effective is IPCC?
Is IPCC expected to be a source of scientific advice for the United
Nations? If so, how is it that the Secretary General continues to assert
that it is still feasible to keep global warming from exceeding the
1.5°C limit?
Does IPCC operate under the rules of science? We ask because the paper Ice
melt, sea level rise and superstorms: evidence from paleoclimate data,
climate modeling, and modern observations that 2 C global warming could
be dangerous,[9] which we submitted and published a decade ago, is
not mentioned in the most recent (2021) IPCC assessment report
(AR6).[10] Our Ice Melt paper addresses the objective of the United Nations Framework Convention on Climate Change,[11] to
“…prevent dangerous anthropogenic interference with the climate
system,” concluding that continued high GHG emissions are likely to
cause shutdown of the AMOC (Atlantic Meridional Overturning Circulation)
near mid-century and multi-meter sea level rise on the century
time-scale, conclusions that strongly conflict with IPCC’s AR6
assessment. Our paper – because of its strong conclusions – faced and
passed extensive peer-review. IPCC seems to believe that it has been
granted special powers and does not need to follow the scientific
method.
Does IPCC explain the core issues in a transparent fashion,
understandable to policymakers? Despite great progress in clean energy
development (solar, wind, geothermal), global warming has accelerated,
as the growth rate of the human-made climate forcing is increasing, not
declining (Fig. 1). The changing drive for climate change exposed by the
colorful diagram – climate forcing caused by greenhouse gas (GHG)
changes – is only part of the story, but it is the most important part
and deserves greater exposure. However, IPCC’s method for projecting
future GHG forcing – “integrated assessment models (IAMs)” that produce
the RCP scenarios – are dark boxes. We must, and will, produce more
transparent projections that are more clearly related to feasible policy
choices.
Policy choices in the next 5-10 years will be crucial for determining
the world that today’s young people and their children will live in.
Although that was also true 10 years ago and 20 years ago, the situation
is different now. Now we are well into the period of consequences and
now the danger of passing the global irreversible point-of-no-return has
increased markedly.
The present global approach for addressing climate change is not only
ineffectual wishful-thinking, it is irresponsible. Phasedown of GHG
emissions requires effective policies on decadal time scales, not
mid-century targets that permit obfuscation of the absence of effective
policy.
Reassessment of the climate change situation requires quantification of
policy alternatives. Reassessment must be based on the scientific
method.
Note: the link to our last communication, which did not work for some people, is now on YouTube at A Climate Talk in Helsinki
Definition:
a climate forcing is an imposed perturbation of Earth’s energy balance.
For example, if the brightness of the Sun increased 2%, that would be
an effective climate forcing of about +4 W/m2, where W/m2 is watts per square meter averaged over Earth’s surface. The forcing caused by doubling the amount of carbon dioxide (CO2) in Earth’s atmosphere is also about +4 W/m2, because the added CO2 reduces Earth’s heat radiation to space by about 4 W/m2.
The net human-made climate forcing is probably about +2.5-3 W/m2,
because human-made aerosols (fine airborne particles) increase
reflection of sunlight to space by an amount that is not well-measured,
but is probably[12] 1-1.5 W/m2.
Earth responds to this energy imbalance (more energy coming in than
going out) by warming. Warming continues until Earth is radiating to
space as much energy as it is absorbing from the Sun, and thus
equilibrium (energy balance) is restored. Because of the large heat
capacity of the ocean, it takes a long time to approach a new
equilibrium. Today, Earth is still out of energy balance by about +1 W/m2, so there is still substantial warming “in the pipeline,” even without further increase of atmospheric greenhouse gases (GHGs).
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