SIXTH FRAMEWORK PROGRAMME
Project no: 502687
NEEDS
New Energy Externalities Developments for Sustainability
INTEGRATED PROJECT Priority 6.1: Sustainable Energy Systems and, more specifically,
Sub-priority 6.1.3.2.5: Socio-economic tools and concepts for energy strategy.
Delivery n° 5.4 - RS 1b
“Report on marginal external damage costs
inventory of greenhouse gas emissions
Due date of technical paper: Feb 2007
Actual submission date: September 2007
Start date of project: 1 September 2004 Duration: 48 months
Organisation name for this technical paper: David Anthoff
Authors: David Anthoff
Project co-funded by the European Commission within the Sixth Framework Programme (2004-2008) Dissemination Level
PU Public X
PP Restricted to other programme participants (including the Commission Services)
RE Restricted to a group specified by the consortium (including the Commission Services)
CO Confidential, only for members of the consortium (including the Commission Services)
1
Report on marginal external damage costs of greenhouse gas emissions New Results from FUND 3.0
Version 1.1
26 September 2007
David Anthoff
Revision history Version Date Change
0.9 9 September 2007 Initial report 1.0 24 September 2007 Small layout edits 1.1 26 September 2007 Added discussion of unknown damage categories (p. 4-5)
Added tables with discount rates (p. 9-10)
Introduction
Marginal damage cost of greenhouse gas emission estimates are widely used today to inform
decision making on climate change mitigation and adaptation. The marginal damage cost of carbon is
commonly referred to as the Social Cost of Carbon (SCC). Marginal damage figures are not the only
measure used to quantify impacts from climate change, other studies have also presented total
damage costs (e.g. Nordhaus and Boyer 2000; Tol 2002; Tol 2002) and more recently new measures
like changes in the balanced growth equivalent (Stern 2006) have been used. Nevertheless, marginal
damage estimates of carbon emissions seem to be most numerous in the literature, and today meta-
studies of marginal damage estimates give a comprehensive overview of these studies (Tol 2005; Tol
2007).
Estimates of the social cost of carbon differ not only because the underlying integrated assessment
models represent key climate and socio-economic relations differently, but also because there are a
number of assumptions to be made to which these estimates are highly sensitive, which cannot
easily be resolved. Examples include the choice of discount rate, the treatment of uncertainty and
the use of equity weighting. Due to this structure of the problem, one can generate a large range of
2
social cost of carbon estimates even from a single model, by just changing a few key assumptions for
different model runs.
This report discusses a set of new model results from the integrated assessment model FUND 3.0 and
in particular outlines the assumptions made in different model runs.
Model
This paper uses version 3.0 of the Climate Framework for Uncertainty, Negotiation and Distribution
(FUND). Version 3.0 of FUND corresponds to version 1.6, described and applied by Tol (1999; 2001;
2002), except for the impact module, which is described by Tol (2002; 2002) and updated by Link and
Tol (2004). A further difference is that the current version of the model distinguishes 16 instead of 9
regions. Readers familiar with FUND can skip this section.
Essentially, FUND consists of a set of exogenous scenarios and endogenous perturbations. The model
distinguishes 16 major regions of the world, viz. the United States of America, Canada, Western
Europe, Japan and South Korea, Australia and New Zealand, Central and Eastern Europe, the former
Soviet Union, the Middle East, Central America, South America, South Asia, Southeast Asia, China,
North Africa, Sub-Saharan Africa, and Small Island States. The model runs from 1950 to 2300 in time
steps of one year. The prime reason for starting in 1950 is to initialize the climate change impact
module. In FUND, the impacts of climate change are assumed to depend on the impact of the
previous year, this way reflecting the process of adjustment to climate change. Because the initial
values to be used for the year 1950 cannot be approximated very well, both physical and monetized
impacts of climate change tend to be misrepresented in the first few decades of the model runs. The
22nd and 23rd centuries are included to account for the fact that climate change does not stop in
2100.
The period of 1950-1990 is used for the calibration of the model, which is based on the IMAGE 100-
year database (Batjes and Goldewijk 1994). The period 1990-2000 is based on observations (World
3
Resources Institute 2000). The climate scenarios for the period 2010-2100 are based on the EMF14
Standardized Scenario, which lies somewhere in between IS92a and IS92f (Leggett, Pepper et al.
1992). The 2000-2010 period is interpolated from the immediate past, and the period 2100-2300
extrapolated.
The scenarios are defined by the rates of population growth, economic growth, autonomous energy
efficiency improvements as well as the rate of decarbonisation of the energy use (autonomous
carbon efficiency improvements), and emissions of carbon dioxide from land use change, methane
and nitrous oxide. The scenarios of economic and population growth are perturbed by the impact of
climatic change. Population decreases with increasing climate change related deaths that result from
changes in heat stress, cold stress, malaria, and tropical cyclones. Heat and cold stress are assumed
to have an effect only on the elderly, non-reproductive population. In contrast, the other sources of
mortality also affect the number of births. Heat stress only affects the urban population. The share of
the urban population among the total population is based on the World Resources Databases (World
Resources Institute 2000). It is extrapolated based on the statistical relationship between
urbanization and per-capita income, which are estimated from a cross-section of countries in 1995.
Climate-induced migration between the regions of the world also causes the population sizes to
change. Immigrants are assumed to assimilate immediately and completely with the respective host
population.
The tangible impacts are dead-weight losses to the economy. Consumption and investment are
reduced without changing the savings rate. As a result, climate change reduces long-term economic
growth, although consumption is particularly affected in the short-term. Economic growth is also
reduced by carbon dioxide abatement measures. The energy intensity of the economy and the
carbon intensity of the energy supply autonomously decrease over time.
The endogenous parts of FUND consist of the atmospheric concentrations of carbon dioxide,
methane and nitrous oxide, the global mean temperature, the impact of carbon dioxide emission
4
reductions on the economy and on emissions, and the impact of the damages to the economy and
the population caused by climate change. Methane and nitrous oxide are taken up in the
atmosphere, and then geometrically depleted. The atmospheric concentration of carbon dioxide,
measured in parts per million by volume, is represented by the five-box model of Maier-Reimer and
Hasselmann (1987). Its parameters are taken from Hammitt et al. (1992). The model also contains
sulphur emissions (Tol 2006).
The radiative forcing of carbon dioxide, methane, nitrous oxide and sulphur aerosols is determined
based on Shine et al. (Shine, Derwent et al. 1990). The global mean temperature T is governed by a
geometric build-up to its equilibrium (determined by the radiative forcing RF), with a half-life of 50
years. In the base case, the global mean temperature rises in equilibrium by 2.5°C for a doubling of
carbon dioxide equivalents. Regional temperature follows from multiplying the global mean
temperature by a fixed factor, which corresponds to the spatial climate change pattern averaged
over 14 GCMs (Mendelsohn, Morrison et al. 2000). The global mean sea level is also geometric, with
its equilibrium level determined by the temperature and a half-life of 50 years. Both temperature
and sea level are calibrated to correspond to the best guess temperature and sea level for the IS92a
scenario of Kattenberg et al.(1996).
The climate impact module, based on Tol (2002; 2002) includes the following categories: agriculture,
forestry, sea level rise, cardiovascular and respiratory disorders related to cold and heat stress,
malaria, dengue fever, schistosomiasis, diarrhoea, energy consumption, water resources, and
unmanaged ecosystems. There has been some discussion of other damage categories in the
literature (cf. section 3.2.1 in Watkiss, Anthoff et al. 2005), but neither have they been modeled in a
quantitative way, nor can one even strictly say whether they will be damages or benefits. Such
damage categories are not included in FUND, but it would be pure speculation to say that this biases
the damage estimates up or down or whether they would make a large or small difference to the
results. Climate change related damages can be attributed to either the rate of change
5
(benchmarked at 0.04°C/yr) or the level of change (benchmarked at 1.0°C). Damages from the rate of
temperature change slowly fade, reflecting adaptation (cf. Tol 2002).
People can die prematurely due to temperature stress or vector-borne diseases, or they can migrate
because of sea level rise. Like all impacts of climate change, these effects are monetized. The value of
a statistical life is set to be 200 times the annual per capita income. The resulting value of a statistical
life lies in the middle of the observed range of values in the literature (cf. Cline 1992). The value of
emigration is set to be 3 times the per capita income (Tol 1995; Tol 1996), the value of immigration is
40 per cent of the per capita income in the host region (Cline 1992). Losses of dryland and wetlands
due to sea level rise are modelled explicitly. The monetary value of a loss of one square kilometre of
dryland was on average $4 million in OECD countries in 1990 (cf. Fankhauser 1994). Dryland value is
assumed to be proportional to GDP per square kilometre. Wetland losses are valued at $2 million per
square kilometre on average in the OECD in 1990 (cf. Fankhauser 1994). The wetland value is
assumed to have logistic relation to per capita income. Coastal protection is based on cost-benefit
analysis, including the value of additional wetland lost due to the construction of dikes and
subsequent coastal squeeze.
Other impact categories, such as agriculture, forestry, energy, water, and ecosystems, are directly
expressed in monetary values without an intermediate layer of impacts measured in their ‘natural’
units (cf. Tol 2002). Impacts of climate change on energy consumption, agriculture, and
cardiovascular and respiratory diseases explicitly recognize that there is a climatic optimum, which is
determined by a variety of factors, including plant physiology and the behavior of farmers. Impacts
are positive or negative depending on whether the actual climate conditions are moving closer to or
away from that optimum climate. Impacts are larger if the initial climate conditions are further away
from the optimum climate. The optimum climate is of importance with regard to the potential
impacts. The actual impacts lag behind the potential impacts, depending on the speed of adaptation.
The impacts of not being fully adapted to new climate conditions are always negative (cf. Tol 2002).
6
The impacts of climate change on coastal zones, forestry, unmanaged ecosystems, water resources,
diarrhoea malaria, dengue fever, and schistosomiasis are modelled as simple power functions.
Impacts are either negative or positive, and they do not change sign (cf. Tol 2002).
Vulnerability to climate change changes with population growth, economic growth, and technological
progress. Some systems are expected to become more vulnerable, such as water resources (with
population growth), heat-related disorders (with urbanization), and ecosystems and health (with
higher per capita incomes). Other systems are projected to become less vulnerable, such as energy
consumption (with technological progress), agriculture (with economic growth) and vector- and
water-borne diseases (with improved health care) (cf. Tol 2002).
Dimensions of results
The set of results for this model exercise is fairly large. This section will attempt to categorize the
results along various dimensions, explain the parameter choices made for each dimension and give
recommendations on what values should be considered for policy decisions in what way. It will not
attempted to give a full theoretical foundation for all possible parameter choices, but where
adequate references to the appropriate background literature are given. This section is best thought
of as guideline to the result set, it should enable consumers of the accompanying data sets to pick
the right number for further applications from the set of estimates provided.
Physical dimensions
Different gases
This study not only calculates the social cost of carbon, i.e. the marginal damage from an extra ton of
carbon emission, but in addition includes estimates for three other greenhouse gases as well: The
marginal damage of CH4, N2O and SF6 emissions. The procedure to calculate the four marginal
damage figures for the four gases is exactly the same, in each case the model is run twice and the
second run is perturbed by a small, marginal extra emission of the specific gas, after which the
difference in damages between the runs is produced to come to a marginal damage estimate.
7
Recommendation
The proper value to look at depends on what gas is emitted in a project, the corresponding marginal
damage figure for that gas should be used.
Different emission periods
Marginal damage estimates are also calculated for different marginal emission periods, in particular
for various emission periods over the next century. It is well known that an extra ton of greenhouse
gas emission today has a different impact on societies than an extra ton of the same greenhouse gas
emission at a later point in time. The main reason for this is the increase in greenhouse gas
concentrations in the atmosphere due to the baseline socio-economic scenario and the non-linear
response of damages to greenhouse gas concentration changes in the atmosphere.
The marginal damage estimates over time start in the year 2005 for this report and are then
calculated in ten year steps up to the year 2095. Ideally one would want to include damages from the
same time span after the date of the marginal emission for all these estimates. Assuming for example
that one is looking at a 300 year time frame, one would ideally want marginal damage estimates that
include all damages caused by the extra emission that occur in the next 300 years after the marginal
emission, e.g. one would want the marginal damage estimates for the year 2015 to include damages
in the years 2015-2315 and estimates for the year 2045 to include damages in the years 2045-2345.
The results presented in this paper do not follow this theoretical ideal, rather the cut of point is
always the end of the time period the model runs to, i.e. damages are always taken into account up
to the year 2300. This is a pragmatic approach, mainly chosen because the model is not build to run
longer than to the year 2300 and at the same time the wish to not artificially truncate marginal
damage estimates for early periods at an earlier date (i.e. one could have limited the damages
considered for SCC figures to the next 200 years after the marginal emission), in particular given that
significant portions of the damage only occur in later time periods.
8
Recommendation
In a cost-benefit analysis one should look at the precise year a particular emission is expected to
happen and use the marginal damage emission for that time period when calculating the damages
caused by the project.
Preference dimensions
Implicitly or explicitly any marginal damage estimate of climate change is based on some ranking of
outcomes, i.e. is based on some preference ordering that a potential decision maker is assumed to
hold. There is no consensus on what the “right” or correct preference order should be, and indeed it
is commonly assumed that this question is one that cannot be answered by simple scientific
investigation. In particular, economics as a discipline can only to some degree help with the choice of
preference ordering a decision maker should hold: It can mainly test a given preference ordering for
consistency with for example opinions hold by the public or consistency with other decisions already
made.
For this reason this report presents a variety of results assuming different preference orders, mainly
along two dimension of choice: Discounting and equity weighting.
Discounting
FUND uses the usual Ramsey style discounting, that is the actually discount rate used for discounting
the marginal damage figures is calculated as a combination of the consumption growth rate, the risk
aversion or more general curvature of the utility function parameter and the pure rate of time
preference (also called the utility discount rate). Following most of the literature, the risk aversion
parameter is always set to 1, so that the final discount factor 𝐷𝐹𝑡 ,𝑟 for time 𝑡 and region 𝑟 is
𝐷𝐹𝑡 ,𝑟 =1
1 + 𝜌 + 𝑔𝑖 ,𝑟𝑡𝑖=0
where 𝑔𝑡 ,𝑟 is the per capita consumption growth rate in region 𝑟 at time 𝑡 and 𝜌 is the pure rate of
time preference. The results presented in this report are calculated for three different choices of
9
pure rate of time preference, namely 0%, 1% and 3%. The choice of time preference rate constitutes
a real change in the preference order which implicitly underlies the cost-benefit analysis and from
which the discount factor is derived.
The effective discount rates used even for a specific pure rate of time preference varies over time
and region, since per capita consumption growth rates vary over time and by region. To enable some
comparison with other studies, selected equivalent constant consumption discount rates1 for results
that are discounted back to the year 2005 are presented in the following tables:
Year USA CAN WEU JPK ANZ EEU FSU MDE CAM LAM SAS SEA CHI MAF SSA SIS
2006 1.7% 1.9% 1.9% 2.0% 2.0% 2.8% 2.8% 1.1% 1.6% 1.6% 2.8% 3.4% 3.4% 1.6% 1.6% 1.6%
2050 1.5% 1.6% 1.6% 1.6% 1.6% 3.0% 3.0% 2.3% 2.4% 2.4% 2.5% 2.5% 2.9% 2.4% 2.4% 2.4%
2100 1.3% 1.3% 1.3% 1.3% 1.3% 2.3% 2.3% 2.4% 2.4% 2.4% 2.4% 2.4% 2.8% 2.4% 2.4% 2.4%
2150 1.1% 1.1% 1.1% 1.1% 1.1% 1.8% 1.8% 2.1% 2.1% 2.1% 2.1% 2.1% 2.3% 2.1% 2.1% 2.1%
2200 1.0% 1.0% 1.0% 1.0% 1.0% 1.6% 1.6% 1.8% 1.8% 1.8% 1.8% 1.8% 2.0% 1.8% 1.8% 1.8%
2250 0.9% 0.9% 0.9% 0.9% 0.9% 1.4% 1.4% 1.6% 1.6% 1.6% 1.6% 1.6% 1.8% 1.6% 1.6% 1.6%
Table 1: Equivalent constant discount rates for pure rate of time preference of 0%
Year USA CAN WEU JPK ANZ EEU FSU MDE CAM LAM SAS SEA CHI MAF SSA SIS
2006 2.7% 2.9% 2.9% 3.0% 3.0% 3.8% 3.8% 2.1% 2.6% 2.6% 3.8% 4.4% 4.4% 2.6% 2.6% 2.6%
2050 2.5% 2.6% 2.6% 2.6% 2.6% 4.0% 4.0% 3.3% 3.4% 3.4% 3.5% 3.5% 3.9% 3.4% 3.4% 3.4%
2100 2.3% 2.3% 2.3% 2.3% 2.3% 3.3% 3.3% 3.4% 3.4% 3.4% 3.4% 3.4% 3.8% 3.4% 3.4% 3.4%
2150 2.1% 2.1% 2.1% 2.1% 2.1% 2.8% 2.8% 3.1% 3.1% 3.1% 3.1% 3.1% 3.3% 3.1% 3.1% 3.1%
2200 2.0% 2.0% 2.0% 2.0% 2.0% 2.6% 2.6% 2.8% 2.8% 2.8% 2.8% 2.8% 3.0% 2.8% 2.8% 2.8%
2250 1.9% 1.9% 1.9% 1.9% 1.9% 2.4% 2.4% 2.6% 2.6% 2.6% 2.6% 2.6% 2.8% 2.6% 2.6% 2.6%
Table 2: Equivalent constant discount rates for pure rate of time preference of 1%
1 The equivalent constant consumption discount rate 𝐸𝐷𝑅𝑡 ,𝑟 for the year 𝑡 and region 𝑟 is defined as follows:
1
1+𝐸𝐷𝑅𝑡 ,𝑟 𝑡 =
1
1+𝜌+𝑔𝑖 ,𝑟𝑡𝑖=0
, where 𝜌 is the pure rate of time preference and 𝑔𝑡 ,𝑟 is the average per capita growth
rate in year 𝑡 in region 𝑟.
10
Year USA CAN WEU JPK ANZ EEU FSU MDE CAM LAM SAS SEA CHI MAF SSA SIS
2006 4.7% 4.9% 4.9% 5.0% 5.0% 5.8% 5.8% 4.1% 4.6% 4.6% 5.8% 6.4% 6.4% 4.6% 4.6% 4.6%
2050 4.5% 4.6% 4.6% 4.6% 4.6% 6.0% 6.0% 5.3% 5.4% 5.4% 5.5% 5.5% 5.9% 5.4% 5.4% 5.4%
2100 4.3% 4.3% 4.3% 4.3% 4.3% 5.3% 5.3% 5.4% 5.4% 5.4% 5.4% 5.4% 5.8% 5.4% 5.4% 5.4%
2150 4.1% 4.1% 4.1% 4.1% 4.1% 4.8% 4.8% 5.1% 5.1% 5.1% 5.1% 5.1% 5.3% 5.1% 5.1% 5.1%
2200 4.0% 4.0% 4.0% 4.0% 4.0% 4.6% 4.6% 4.8% 4.8% 4.8% 4.8% 4.8% 5.0% 4.8% 4.8% 4.8%
2250 3.9% 3.9% 3.9% 3.9% 3.9% 4.4% 4.4% 4.6% 4.6% 4.6% 4.6% 4.6% 4.8% 4.6% 4.6% 4.6%
Table 3: Equivalent constant discount rates for pure rate of time preference of 3%
In recent years it has also been argued that discount rates should be declining (Weitzman 1998;
Weitzman 2001; Pearce, Groom et al. 2003; Groom, Hepburn et al. 2005), mainly because the future
is uncertain. Such results are present in this report in two ways: For probabilistic runs, i.e. results
from Monte Carlo simulations, this will effectively happen automatically, since the discount rate is
derived from an uncertain consumption growth rate. That is, for probabilistic runs, the stochastic
discount rate will be declining for constant pure rate of time preference choices. For deterministic, so
called “Best Guess” results, this report contains results that are discounted with a declining discount
rate according to the UK Greenbook guidelines for long term discounting (see H.M. Treasury 2003
annex 6 for the detailed discount rate schedule). Note the declining discounting numbers are only
explicitly presented for best guess results, because for probabilistic runs all discounting schemes will
essentially have a declining discount rate. Also note that it is unclear how one would combine equity
weights with a declining discount rate in a deterministic setting, so that no such results are
presented.
Recommendation
If one wants to come up with climate change policies that are consistent with expressed preferences
of consumers and other observed decision of national policy makers, it is essential to use a discount
rate that is somewhere close to observed interest rates. In combination with the parameter chosen
for the curvature of the utility function for FUND, the standard approach would be to use a 3% pure
rate of time preference. In order to account for the fact that uncertain discount rates decline, one
should ideally use probabilistic results, or, if that is not possible, use the declining discount rate
scheme.
11
Results with 0% pure rate of time preference might be a helpful reminder what a decision maker who
has no preference for the current generation would do.
Equity weighting
Besides discounting, where the problem is to pick a representation of a preference order that fits a
decision makers intertemporal substitutability of consumption, there is a choice between attitudes
towards inequality within a generation, i.e. towards inequality between people. In an integrated
assessment model like FUND, with coarse geographical resolution, this is represented as an attitude
towards inequality in average per capita income between different regions.
For this report, two different schemes are used. One is commonly referred to as results that are
“equity weighted”, the other as results without equity weights. For results that are equity weighted,
there is a further question of how to present such numbers, in particular the question of
normalization. But the choice of normalization is not a choice between different preference orders, it
simply is a choice between different units of presenting equity weighted results. The question of
normalization will therefore be discussed in more detail in the section on presentation dimensions.
The difference between equity weighted and non equity weighted social cost of carbon estimates is
best demonstrated by looking at the underlying welfare functions for the two schemes. Equity
weighted social cost of carbon figures follow directly from a standard, utilitarian welfare function of a
global, benevolent planner:
𝑊𝑒𝑤 = 𝑈 𝐶𝑡 ,𝑟 𝑃𝑡 ,𝑟 1 + 𝜌 −𝑡
𝑟
𝑇
𝑡=0
where 𝑇 is the end of the time period considered, 𝑈 ⋅ is the utility function, 𝐶𝑡,𝑟 is average per capita
income and 𝑃𝑡 ,𝑟 is population in region 𝑟 at time 𝑡 and 𝜌 is the pure rate of time preference. Note
that there aren’t any weights in this welfare function. If one derives the equation for the social cost
of carbon from this welfare function (see Anthoff, Hepburn et al. 2006 for a detailed derivation), one
gets
12
𝑆𝐶𝐶𝑒𝑤 = 𝐶0
𝐶0,𝑟 𝐷𝑡,𝑟
1
1 + 𝜌 + 𝑔𝑖 ,𝑟𝑡𝑖=0
𝑇
𝑡=0𝑟
where 𝐶𝑡 is world average per capita income at time 𝑡 and 𝐷𝑡 ,𝑟 is the consumption loss in region 𝑟 at
time 𝑡 caused by the marginal emission of the greenhouse gas. The term “equity weighted” comes
from the equity weight 𝐶0/𝐶0,𝑟 in the social cost of carbon equation, i.e. the weight is present in the
SCC calculation, not in the welfare function.
The equity weight has an appealing interpretation: It gives damages in low income regions more
weight than damages in high income regions and that corresponds nicely with the notion of marginal
declining utility of consumption: The higher the income level of an agent is, the less welfare loss he
or she has from the same absolute loss of income, i.e. the same absolute loss of income causes a
higher welfare loss for a poor agent than for a rich agent.
While the welfare function underpinning the equity weighted marginal damage figures is ethically
appealing, there is a huge difficulty in using it for public policy: It is quite obvious that no national
decision maker (or for this matter groups of nations like the European Union) is even close to operate
by the assumed preference order from which equity weighted social cost of carbon figures follow.
The most simple thought experiment one can do to understand why is to think what the optimal
income redistribution following from the underlying welfare function would look like. The answer is
clear: A decision maker having a preference order which is represented by the 𝑊𝑒𝑤 welfare function
would engage in massive income redistributions from high income countries to low income
countries, on a scale that is clearly not the case when one looks at actual decision made by bodies
like the European Union. If the European Union had a preference ordering like 𝑊𝑒𝑤 , one would
expect to see huge income transfers from the EU to very poor countries, orders of magnitudes over
and above what happens in development programs.
If one does not want to implicitly assume a welfare function for which the optimal solution would be
to change the income distribution of the world in the most fundamental way, an alternative is to only
13
look at efficiency and correct the externality failure which the greenhouse gas caused damage is. In
this case the equation to calculate the marginal cost of greenhouse gas emissions is just the standard
present value of the damages:
𝑆𝐶𝐶 = 𝐷𝑡,𝑟
1
1 + 𝜌 + 𝑔𝑖,𝑟𝑡𝑖=0
𝑇
𝑡=0𝑟
More recently even more schemes for a national decision maker have been presented that
investigate more social welfare functions (Anthoff and Tol 2007), but no such results are presented in
this report.
Recommendation
The use of equity weights is not suggested for a regional decision maker, given that one has to
assume a preference order for that decision maker that seems not to be present. As with a low pure
rate of time preference, they might serve as a helpful reminder of what a truly benevolent global
decision maker would do.
Presentation dimensions
Results in this report are presented for different discounting base years and for different equity
weighting normalizations. The various options along these dimensions are best thought of as choices
of presentation, not as a choice between preference orderings. While the numerical figures for
marginal damage estimates that are discounted to different base years might differ widely, they
really represent the same underlying result, i.e. if they are used properly in follow up analysis, it
doesn’t matter to which base year a figure is discounted. This of course implies that in follow up
studies there are certain rules to be followed depending on the choice presentation one has made
for the marginal damage estimate. In this section the choices for discounting base year and equity
weighting normalization are investigated and explained.
14
Discounting base year
Marginal damage estimates of greenhouse gas emissions differ depending on the timing of the
marginal emission. Therefore, this report presents marginal damage estimates for different emission
years, i.e. marginal damage estimates over time. For marginal damage estimates in the present, it is
natural to discount them to the present, but once one looks at marginal emissions at a later time, the
question arises as to what base year one should pick for the discounting. Two choices emerge: One
can either discount everything back to the present, or one can discount back to the year of emission.
Assuming that 𝑡 = 0 is the present and that one is looking at the marginal damage from an emission
at a later time 𝑡∗ > 0, the marginal damage estimate without equity weighting, discounted to the
present is given by
𝑆𝐶𝐶0 = 𝐷𝑡 ,𝑟
1
1 + 𝜌 + 𝑔𝑖 ,𝑟𝑡𝑖=0𝑟
𝑇
𝑡=𝑡∗
while the marginal damage estimate discounted to the year of the emission is given by
𝑆𝐶𝐶𝑡∗ = 𝐷𝑡,𝑟
1
1 + 𝜌 + 𝑔𝑖,𝑟𝑡𝑖=𝑡∗𝑟
𝑇
𝑡=𝑡∗
where the only difference between the two equations is what discount rates are included in the
discount factor (note that 𝑆𝐶𝐶0 includes all discount rates from time 0 on, while 𝑆𝐶𝐶𝑡∗ only includes
the discount rates starting from time 𝑡∗).
One normally thinks of discounting as the procedure to convert cost or benefits in the future into
their net present value (NPV). What one is really doing when one is calculating marginal damage
costs and discounts them to the year of the emission is calculate the net “year of emission” value.
Both values can be useful, it is just important that in a cost benefit analysis one always only combines
values that are discounted to the same time, ideally one should operate with the net present value.
Situations where the figures that are discounted to the year of emission are useful are for example
when they are further processed by another model: that model might take as an input the marginal
15
damage of greenhouse gas emissions in the year 2020, then do some further calculations and
internally will then discount its results back to the present, i.e. 2005. In such a case it would be wrong
to use the net present value as the input into this model. In general, the proper procedure is to make
sure that at some point everything is discounted back to the present, whether that is done in one
step or in two steps, where things are first discounted to the year of emission and then later from the
year of emission to the present does not matter.
Recommendation
Unless results are to be used in further calculations that will then discount back to the year 2005, one
should avoid numbers that are discounted to the year of emission and rather use marginal damage
estimates that are discounted to 2005 in the first place.
Equity weighting normalization
The issue of normalization of equity weighted results is closely related to the calibration of the
welfare function. With the type of utilitarian welfare function used in FUND, the same preference
order can be represented by any positive, linear transformation of the welfare function we have
looked at so far. In particular, the following welfare function will represent the same preference
ordering for all 𝛼 > 0:
𝑊 = 𝛼 𝑈 𝐶𝑡 ,𝑟 𝑃𝑡 ,𝑟 1 + 𝜌 −𝑡
𝑟
𝑇
𝑡=0
As such, for a given preference structure, there is not one “right” welfare function, but rather many,
that equally represent this preference order. From each of these many welfare functions, one can
derive an equation to calculate the marginal damage of greenhouse gas emissions, and equally
equations that ought to be used to weight any cost or benefit in a project appraisal. As long as one
consistently uses only one set of equations in a given cost-benefit analysis, the results of such a
decision problem will be the same, regardless from which linear transformation of the welfare
function on derives these equations. The key message here is to make sure to always use only
16
numbers in one cost-benefit analysis that have been weighted by equations that are derived from
the same linear transformation of the welfare function.
In this report, marginal damage estimates from two different linear transformations of the welfare
function for equity weighted results are presented. The first is labeled as “normalized to world
average per capita income”. Here 𝛼 is picked such that the equation for the marginal damage (for an
emission in the present) is
𝑆𝐶𝐶𝑒𝑤 ,𝑤𝑜𝑟𝑙𝑑 𝑎𝑣𝑒𝑟𝑎𝑔𝑒 = 𝐶0
𝐶0,𝑟 𝐷𝑡 ,𝑟
1
1 + 𝜌 + 𝑔𝑖 ,𝑟𝑡𝑖=0
𝑇
𝑡=0𝑟
that is, damages are first discounted by the standard Ramsey discounting rule within every region,
then weighted with a weight that gives more (less) weight to damages in regions that have an
average per capita income below (above) the world average. Of course, if this number is to be used
in a cost-benefit analysis, any other cost or benefit must be weighted by this regional weight as well,
in particular if e.g. a region like the European Union was to use that number in a cost-benefit
analysis, it would have to weigh any other number, like for example abatement costs, with the
appropriate regional equity weight. The European Union has an average per capita consumption well
above world average, so that it would have to weight any abatement or other cost with a weight
below unity. If this is done consistently, there is no problem, but in practice this seems hardly
feasible, in particular when numbers like the marginal damage estimates are handed over to
different research groups and this caveat on how they can be used might get lost.
To circumvent this problem, it has been suggested to instead us marginal damage estimates that are
derived from a different transformation of the welfare function (Anthoff, Hepburn et al. 2006) and
such numbers are also reported here. They are labeled as “normalized to west Europe”, and the
equation to calculate such SCC figures is
17
𝑆𝐶𝐶𝑒𝑤 ,𝑤𝑒𝑠𝑡 𝐸𝑢𝑟𝑜𝑝𝑒 = 𝐶0,𝑊𝐸𝑈
𝐶0,𝑟 𝐷𝑡,𝑟
1
1 + 𝜌 + 𝑔𝑖 ,𝑟𝑡𝑖=0
𝑇
𝑡=0𝑟
where 𝐶0,𝑊𝐸𝑈 is average per capita consumption in west Europe in the present. With this
normalization the regional weight for the European Union obviously is unity and therefore just drops
out. This greatly simplifies things: In a cost-benefit analysis, any cost or benefit within the European
Union can just be discounted by the normal standards and be used directly, without applying further
equity weights to it.
Recommendation
If equity weighted numbers are used, one should use those that are normalized to the region in
which the decision is taking place, since this will greatly reduce the complexities of comparing it with
other numbers.
Uncertainty
The uncertainties surrounding estimates of marginal greenhouse gas damages are huge. These
uncertainties stem from a variety of sources, including uncertainty about scenarios of socio-
economic development, non-perfect knowledge of the physical processes occurring in the
atmosphere, difficulties in assessing the magnitudes of impacts, impacts that are not included in
models like FUND and many more (see Downing, Anthoff et al. 2005 for a systematic treatment of
these uncertainties). One dimension of uncertainties is dealt with explicitly in this report, and that is
uncertainties about precise parameter values. FUND can be run in a deterministic mode, in which
case the model is run exactly once and the best guess value for all input parameters is used. The
result obtained from such a run is also called the best guess result. But for many of these input
parameters the best guess is not the whole story: In many cases the true value for the parameter is
unknown. To investigate these uncertainties, FUND can be run in a probabilistic mode, where a
Monte Carlo simulation is performed. In that case the model is run for 1000 times, and for each run
the input parameters are sampled from probability distributions for each parameter. These
distributions are sometimes taken from the scientific literature, when such information is provided
18
by the underlying studies, sometimes they are expert judgments of the model builder. In any case, it
is assumed that such probabilistic runs are more appropriate for issues as uncertain as climate
change.
The standard way to then aggregate the results of these 1000 runs back into one number would be
to take the arithmetic mean, i.e. calculate the expected value. Such numbers are presented in this
report, but a practical problem shows in this case: With only a 1000 runs there is a fair chance of
extreme outliers being part of the sample, i.e. of runs where values for the input parameters are
extremely large or small, and whose likelihood according to the distribution for the parameter is
much smaller than 1/1000. This is a general problem of Monte Carlo simulations with a limited
number of runs. Such outliers will improperly alter the arithmetic mean of the simulation. The proper
solution to this would be to drastically increase the number of runs and thereby reducing the chance
of such outliers significantly, but due to computational constraints this is not feasible with today’s
hardware with a model like FUND. An alternative is to calculate the mean of a trimmed set of
numbers, i.e. calculate the mean not of the result of the 1000 runs, but rather take out e.g. the 5% of
values of that set at each extreme side (i.e. the highest and lowest 2.5%) and then calculate the mean
of the remaining results. This will solve the problem of outliers, but introduces problems by itself, in
particular if one assumes that the nature of the climate change decision problem is such that the
very tails of such probability distributions of results dominate the rational decision (Weitzman 2007).
If this is indeed the case, truncating the samples also implies that one truncates the most important
runs and is actually getting further away from the appropriate result. At this point, the question
whether the tails of the distribution dominate the decision problem, as Weitzman (2007) argues, is
an open research question, but if he is right, all of the current state of the art integrated assessment
models, including FUND, are at this point not sampling into these tails and would therefore not
reflect this line of thinking. Given that it is unclear at this point what the appropriate measure is, this
report presents trimmed and untrimmed results as well as another indicator, namely the median of
the distribution of results.
19
Recommendation
In general, results from probabilistic runs capture more aspects of the decision problem and
therefore are to be used instead of best guess results whenever possible. On the other hand it is
difficult to give advice as to what precise aggregator of the probability distribution one should use,
given the current research activity surrounding this area.
Bibliography
Anthoff, D., C. Hepburn, et al. (2006). "Equity weighting and the marginal damage costs of climate
change." FNU working papers, from http://www.fnu.zmaw.de/fileadmin/fnu-
files/publication/working-papers/AnthoffHepburnTol2006EquityWeighting.pdf.
Anthoff, D. and R. S. J. Tol (2007). On International Equity Weights and National Decision Making on
Climate Change. FNU Working Paper. Hamburg, Germany, University of Hamburg.
Batjes, J. J. and C. G. M. Goldewijk (1994). The IMAGE 2 Hundred Year (1890-1990) Database of the
Global Environment (HYDE), RIVM, Bilthoven, 410100082.
Cline, W. R. (1992). The Economics of Global Warming. Washington, DC, Institute for International
Economics.
Downing, T., D. Anthoff, et al. (2005). Social Cost of Carbon: A Closer Look at Uncertainty.
Fankhauser, S. (1994). "Protection vs. Retreat -- The Economic Costs of Sea Level Rise." Environment
and Planning A 27: 299-319.
Groom, B., C. Hepburn, et al. (2005). "Discounting the future: the long and the short of it."
Environmental and Resource Economics 31(1).
H.M. Treasury (2003). Annex 6: Discount Rate. Green Book, Appraisal and Evaluation in Central
Government.
Hammitt, J. K., R. J. Lempert, et al. (1992). "A Sequential-Decision Strategy for Abating Climate
Change." Nature 357: 315-318.
20
Kattenberg, A., F. Giorgi, et al. (1996). Climate Models - Projections of Future Climate. Climate
Change 1995: The Science of Climate Change -- Contribution of Working Group I to the
Second Assessment Report of the Intergovernmental Panel on Climate Change. J. T.
Houghton, G. J. Jenkins and J. J. Ephraums. Cambridge Cambridge University Press: 285-357.
Leggett, J., W. J. Pepper, et al. (1992). Emissions scenarios for the IPCC: an update. Climate Change
1992 - The Supplementary Report to the IPCC Scientific Assessment. J. T. Houghton, B. A.
Callander and S. K. Varney. Cambridge, Cambridge University Press: 71-95.
Link, P. M. and R. S. J. Tol (2004). "Possible Economic Impacts of a Shutdown of the Thermohaline
Circulation: an Application of FUND." Portuguese Economic Journal 3(2): 99-114.
Maier-Reimer, E. and K. Hasselmann (1987). "Transport and Storage of Carbon Dioxide in the Ocean:
An Inorganic Ocean Circulation Carbon Cycle Model." Climate Dynamics 2: 63-90.
Mendelsohn, R., W. Morrison, et al. (2000). "Country-specific market impacts of climate change."
Climatic Change 45: 553-569.
Nordhaus, W. and J. Boyer (2000). Warming the World: Economics Models of Global Warming.
Pearce, D. W., B. Groom, et al. (2003). "Valuing the Future - Recent advances in social discounting."
World Economics 4(2): 121-141.
Shine, K. P., R. G. Derwent, et al. (1990). Radiative Forcing of Climate. Change - The IPCC Scientific
Assessment, 1 edn, vol. 1. J. T. Houghton, G. J. Jenkins and J. J. Ephraums. Cambridge
Cambridge University Press: 41-68.
Stern, N. (2006). The Economics of Climate Change. The Stern Review. Cambridge, UK, Cambridge
University Press.
Tol, R. S. J. (1995). "The Damage Costs of Climate Change -- Towards More Comprehensive
Calculations." Environmental and Resource Economics 5: 353-374.
Tol, R. S. J. (1996). "The Damage Costs of Climate Change: Towards a Dynamic Representation."
Ecological Economics 19: 67-90.
21
Tol, R. S. J. (1999). "The Marginal Costs of Greenhouse Gas Emissions." The Energy Journal 20(1): 61-
81.
Tol, R. S. J. (2001). "Equitable cost-benefit analysis of climate change policies." Ecological Economics
36: 71-85.
Tol, R. S. J. (2002). "Estimates of the damage costs of climate change, Part II. Dynamic estimates."
Environmental and Resource Economics 21(2): 135-160.
Tol, R. S. J. (2002). "Estimates of the damage costs of climate change. Part 1: Benchmark estimates."
Environmental and Resource Economics 21(2): 47-73.
Tol, R. S. J. (2002). "Welfare specifications and optimal control of climate change: an application of
fund." Energy Economics 24: 367-76.
Tol, R. S. J. (2005). "The marginal damage costs of carbon dioxide emissions: an assessment of the
uncertainties." Energy Policy 33: 2064–2074.
Tol, R. S. J. (2006). "Multi-Gas Emission Reduction for Climate Change Policy: An Application of
FUND." Energy Journal Multi-Greenhouse Gas Mitigation and Climate Policy Special Issue:
235-250.
Tol, R. S. J. (2007) "The Social Cost of Carbon: Trends, Outliers and Catastrophes." FNU Working
Papers Volume, DOI:
Watkiss, P., D. Anthoff, et al. (2005). The Social Costs of Carbon Review – Methodological Approaches
for Using SCC Estimates in Policy Assessment. London, United Kingdom, Defra.
Weitzman, M. L. (1998). "Why the Far-Distant Future Should Be Discounted at Its Lowest Possible
Rate." Journal of Environmental Economics and Management 36: 201]208.
Weitzman, M. L. (2001). "Gamma Discounting." The American Economic Review 91(1): 260-271.
Weitzman, M. L. (2007). Structural Uncertainty and the Value of Statistical Life in the Economics of
Catastrophic Climate Change.
World Resources Institute (2000). World Resources Database 2000-2001. Washington D.C, World
Resources Institute.
22
23
Results
The model FUND internally uses $ 1995 as its units. Results for this report have been inflation
adjusted to use $ 2005 by using the US consumer price index.
Results that are not equity weighted are labeled “NoEW”, results that are equity weighted and
normalized with average world per capita income are labeled with “AvEW” and those that are
weighted and normalized to the EU are labeled with “WeuEW”.
24
Carbon
Best Guess
Gas C
Best Guess Year of emission
2005 2015 2025 2035 2045 2055 2065 2075 2085 2095
Discounted to 2005
0% pure rate of time preference
NoEW $82.4 $80.7 $78.2 $75.0 $71.3 $67.2 $62.8 $58.4 $54.1 $50.0
AvEW $208.5 $199.7 $190.2 $180.1 $169.5 $158.5 $147.4 $136.5 $126.0 $116.1
WeuEW $993.0 $950.9 $906.0 $857.9 $807.2 $755.0 $702.2 $650.2 $600.1 $552.9
1% pure rate of time preference
NoEW $10.8 $12.0 $12.5 $12.3 $11.7 $10.9 $9.9 $8.8 $7.8 $6.8
AvEW $38.8 $37.3 $35.3 $32.8 $30.0 $27.0 $24.0 $21.1 $18.5 $16.0
WeuEW $184.7 $177.5 $168.1 $156.3 $143.0 $128.8 $114.4 $100.7 $87.9 $76.3
3% pure rate of time preference
NoEW -$6.9 -$3.7 -$1.8 -$0.7 -$0.2 $0.1 $0.2 $0.2 $0.2 $0.2
AvEW -$7.1 -$3.4 -$1.1 $0.1 $0.7 $0.9 $0.8 $0.7 $0.6 $0.5
WeuEW -$34.0 -$16.3 -$5.4 $0.5 $3.2 $4.1 $4.0 $3.5 $2.9 $2.3
Declining discount rate
$19.3 $20.3 $20.4 $19.7 $18.5 $17.1 $15.4 $13.8 $12.2 $10.7
Discounted to year of emission
0% pure rate of time preference
NoEW $82.4 $103.9 $129.0 $158.2 $191.2 $228.1 $271.2 $322.2 $378.8 $433.0
AvEW $208.5 $231.7 $255.5 $279.7 $302.9 $326.0 $351.3 $380.4 $413.9 $446.1
WeuEW $993.0 $1,144.2 $1,291.4 $1,421.4 $1,526.9 $1,603.6 $1,668.7 $1,726.6 $1,769.9 $1,788.8
1% pure rate of time preference
NoEW $10.8 $17.2 $25.4 $35.5 $47.6 $61.6 $78.4 $98.7 $122.0 $145.9
AvEW $38.8 $47.8 $57.8 $68.7 $79.9 $91.5 $104.0 $118.2 $134.4 $150.8
WeuEW $184.7 $235.9 $292.3 $349.1 $402.7 $449.9 $494.1 $536.6 $574.6 $604.8
3% pure rate of time preference
NoEW -$6.9 -$6.3 -$5.0 -$3.0 -$0.4 $3.0 $7.1 $12.2 $18.3 $24.7
AvEW -$7.1 -$5.3 -$2.8 $0.4 $3.9 $7.8 $11.9 $16.4 $21.3 $26.4
WeuEW -$34.0 -$26.3 -$13.9 $1.8 $19.8 $38.2 $56.4 $74.3 $91.1 $105.7
Declining discount rate
$19.3 $24.0 $29.4 $35.3 $41.6 $48.0 $54.3 $60.4 $66.4 $72.4
25
Average
Gas C
Average Year of emission
2005 2015 2025 2035 2045 2055 2065 2075 2085 2095
Discounted to 2005
0% pure rate of time preference
NoEW $200.5 $203.1 $196.1 $208.5 $767.6 $253.2 $122.3 $116.0 $130.5 $106.4
AvEW $460.5 $441.0 $472.0 $371.6 $2,426.9 $342.5 $269.4 $241.2 $404.0 $210.4
WeuEW $2,192.5 $2,099.3 $2,247.0 $1,769.1 $11,558.7 $1,630.6 $1,282.7 $1,148.2 $1,923.2 $1,001.6
1% pure rate of time preference
NoEW $45.0 $45.0 $44.4 $42.3 $139.4 $50.4 $21.9 $20.5 $21.3 $16.2
AvEW $122.5 $111.6 $117.0 $86.4 $385.1 $69.8 $51.1 $44.0 $66.7 $33.1
WeuEW $583.1 $531.2 $557.1 $411.1 $1,834.0 $332.3 $243.4 $209.3 $317.4 $157.6
3% pure rate of time preference
NoEW -$0.5 $1.7 $3.1 $2.7 $10.0 $3.8 $1.2 $1.1 $1.0 $0.7
AvEW $12.3 $11.2 $12.7 $7.8 $17.5 $5.3 $3.3 $2.5 $3.4 $1.4
WeuEW $58.5 $53.3 $60.5 $37.0 $83.4 $25.0 $15.5 $12.1 $16.3 $6.8
Discounted to year of emission
0% pure rate of time preference
NoEW $200.5 $257.6 $319.8 $401.6 $1,621.1 $699.7 $460.7 $569.8 $776.2 $747.0
AvEW $460.5 $511.9 $634.1 $577.4 $4,337.7 $705.3 $642.8 $673.2 $1,328.7 $809.4
WeuEW $2,192.5 $2,526.0 $3,202.7 $2,931.2 $21,863.8 $3,463.8 $3,048.6 $3,049.1 $5,672.0 $3,240.7
1% pure rate of time preference
NoEW $45.0 $63.3 $89.2 $111.7 $436.8 $229.8 $152.6 $205.7 $285.4 $283.8
AvEW $122.5 $143.1 $191.9 $180.9 $1,024.9 $236.4 $221.6 $246.3 $486.1 $311.9
WeuEW $583.1 $706.1 $968.9 $918.0 $5,165.2 $1,161.0 $1,050.9 $1,115.2 $2,075.0 $1,248.7
3% pure rate of time preference
NoEW -$0.5 $3.0 $9.7 $13.3 $66.9 $45.9 $27.5 $45.2 $67.3 $69.4
AvEW $12.3 $17.5 $30.9 $29.4 $102.2 $47.5 $45.9 $56.1 $120.2 $78.6
WeuEW $58.5 $86.1 $155.9 $149.0 $514.4 $233.0 $217.6 $254.1 $512.9 $314.7
26
Average, 1% trimmed
Gas C
Average 1% Year of emission
2005 2015 2025 2035 2045 2055 2065 2075 2085 2095
Discounted to 2005
0% pure rate of time preference
NoEW $158.5 $172.8 $159.1 $134.7 $117.6 $131.9 $100.0 $93.9 $95.5 $83.8
AvEW $381.5 $389.5 $365.5 $281.5 $246.0 $289.3 $212.3 $195.3 $195.8 $169.6
WeuEW $1,816.3 $1,854.6 $1,740.0 $1,340.3 $1,171.3 $1,377.5 $1,010.8 $930.1 $932.5 $807.2
1% pure rate of time preference
NoEW $35.0 $37.7 $34.6 $28.2 $23.3 $25.8 $17.9 $16.2 $15.4 $12.7
AvEW $102.4 $97.3 $89.8 $65.0 $53.6 $59.2 $40.3 $34.8 $32.8 $26.8
WeuEW $487.4 $463.1 $427.4 $309.4 $255.3 $281.9 $191.7 $165.5 $156.3 $127.6
3% pure rate of time preference
NoEW -$2.3 $0.3 $1.4 $1.3 $1.1 $1.6 $0.9 $0.8 $0.7 $0.5
AvEW $8.6 $8.4 $8.5 $5.1 $4.0 $4.3 $2.4 $1.8 $1.6 $1.1
WeuEW $40.9 $40.0 $40.6 $24.3 $18.8 $20.6 $11.5 $8.8 $7.6 $5.4
Discounted to year of emission
0% pure rate of time preference
NoEW $158.5 $219.4 $257.2 $268.3 $290.7 $415.4 $376.2 $452.9 $551.2 $589.6
AvEW $381.5 $452.2 $491.0 $437.5 $440.2 $595.8 $506.4 $545.1 $644.0 $652.5
WeuEW $1,816.3 $2,231.5 $2,480.1 $2,220.8 $2,215.6 $2,926.1 $2,402.3 $2,470.0 $2,750.2 $2,611.8
1% pure rate of time preference
NoEW $35.0 $53.0 $68.8 $76.5 $87.5 $136.2 $124.5 $158.8 $200.7 $225.1
AvEW $102.4 $124.8 $147.2 $136.1 $142.9 $200.5 $174.5 $194.7 $239.3 $252.5
WeuEW $487.4 $615.6 $743.4 $690.9 $719.0 $984.8 $827.5 $881.9 $1,021.8 $1,010.5
3% pure rate of time preference
NoEW -$2.3 $0.7 $4.8 $6.8 $10.2 $24.0 $20.1 $31.4 $44.1 $53.5
AvEW $8.6 $13.1 $20.7 $19.2 $23.1 $39.1 $33.8 $40.9 $55.7 $62.6
WeuEW $40.9 $64.6 $104.5 $97.5 $116.1 $192.0 $160.5 $185.0 $237.8 $250.3
27
Average 5% trimmed
Gas C
Average 5% Year of emission
2005 2015 2025 2035 2045 2055 2065 2075 2085 2095
Discounted to 2005
0% pure rate of time preference
NoEW $123.0 $135.1 $122.3 $101.1 $94.6 $94.1 $81.8 $75.6 $70.9 $66.7
AvEW $299.6 $304.8 $284.1 $218.6 $203.0 $215.6 $178.3 $159.3 $148.0 $131.7
WeuEW $1,426.4 $1,451.1 $1,352.7 $1,040.6 $966.5 $1,026.4 $848.8 $758.6 $704.5 $627.1
1% pure rate of time preference
NoEW $24.2 $27.9 $25.3 $19.6 $18.0 $17.7 $14.2 $12.7 $11.3 $9.9
AvEW $78.3 $76.1 $68.5 $47.9 $43.1 $44.1 $33.1 $28.0 $24.7 $20.5
WeuEW $372.9 $362.5 $326.2 $227.9 $205.3 $210.0 $157.6 $133.4 $117.8 $97.5
3% pure rate of time preference
NoEW -$4.5 -$1.5 $0.0 $0.0 $0.5 $0.8 $0.6 $0.5 $0.5 $0.4
AvEW $3.9 $4.8 $5.2 $2.5 $2.6 $2.9 $1.8 $1.4 $1.1 $0.8
WeuEW $18.7 $22.6 $24.9 $11.9 $12.5 $14.0 $8.5 $6.5 $5.4 $3.8
Discounted to year of emission
0% pure rate of time preference
NoEW $123.0 $171.3 $196.0 $202.2 $233.3 $291.8 $306.9 $357.3 $405.1 $453.1
AvEW $299.6 $353.8 $381.7 $339.6 $363.2 $443.9 $425.2 $444.5 $486.7 $506.8
WeuEW $1,426.4 $1,746.0 $1,927.9 $1,724.3 $1,828.3 $2,180.3 $2,017.2 $2,014.5 $2,077.9 $2,028.9
1% pure rate of time preference
NoEW $24.2 $39.2 $50.1 $53.6 $67.7 $92.3 $98.7 $122.7 $145.6 $168.4
AvEW $78.3 $97.6 $112.3 $100.3 $114.9 $149.4 $143.5 $156.9 $180.4 $193.0
WeuEW $372.9 $481.9 $567.3 $508.9 $578.1 $733.6 $680.6 $711.1 $770.3 $772.4
3% pure rate of time preference
NoEW -$4.5 -$2.4 $0.5 $0.9 $5.1 $12.6 $13.3 $21.1 $29.1 $36.1
AvEW $3.9 $7.4 $12.7 $9.5 $15.3 $26.5 $25.0 $30.3 $39.9 $44.5
WeuEW $18.7 $36.6 $64.0 $47.9 $77.0 $130.3 $118.7 $137.0 $170.3 $177.9
28
Average 10% trimmed
Gas C
Average 10% Year of emission
2005 2015 2025 2035 2045 2055 2065 2075 2085 2095
Discounted to 2005
0% pure rate of time preference
NoEW $101.9 $114.6 $100.4 $81.3 $80.6 $78.3 $68.8 $65.1 $61.1 $55.2
AvEW $257.5 $266.5 $239.9 $183.1 $174.2 $178.0 $152.7 $136.0 $128.3 $110.3
WeuEW $1,225.9 $1,268.8 $1,142.4 $871.6 $829.4 $847.5 $727.1 $647.4 $611.0 $525.2
1% pure rate of time preference
NoEW $18.2 $22.4 $19.6 $14.5 $14.7 $14.2 $11.5 $10.6 $9.6 $8.1
AvEW $65.6 $64.6 $56.9 $38.5 $36.2 $35.6 $27.8 $23.4 $21.2 $16.9
WeuEW $312.5 $307.8 $270.7 $183.5 $172.2 $169.6 $132.5 $111.6 $100.8 $80.3
3% pure rate of time preference
NoEW -$5.7 -$2.4 -$0.9 -$0.7 $0.1 $0.5 $0.3 $0.4 $0.4 $0.3
AvEW $1.2 $2.6 $3.4 $1.1 $1.8 $2.1 $1.3 $1.0 $0.9 $0.6
WeuEW $5.7 $12.3 $16.3 $5.3 $8.5 $10.0 $6.3 $5.0 $4.4 $3.0
Discounted to year of emission
0% pure rate of time preference
NoEW $101.9 $145.5 $161.0 $163.3 $198.5 $240.6 $255.3 $302.3 $343.7 $374.9
AvEW $257.5 $309.3 $322.3 $284.4 $311.6 $366.4 $364.2 $379.3 $422.0 $424.5
WeuEW $1,225.9 $1,526.6 $1,628.3 $1,444.3 $1,568.9 $1,800.4 $1,727.9 $1,719.2 $1,802.0 $1,699.2
1% pure rate of time preference
NoEW $18.2 $31.5 $38.9 $39.8 $55.1 $73.0 $78.9 $100.6 $121.3 $136.1
AvEW $65.6 $82.9 $93.2 $80.7 $96.3 $120.6 $120.6 $131.3 $154.3 $159.0
WeuEW $312.5 $409.1 $470.8 $409.7 $484.9 $592.5 $572.0 $595.0 $659.0 $636.4
3% pure rate of time preference
NoEW -$5.7 -$4.1 -$2.0 -$2.9 $1.8 $7.2 $8.1 $14.9 $22.1 $26.4
AvEW $1.2 $4.0 $8.3 $4.3 $10.4 $18.9 $18.5 $23.2 $32.3 $34.1
WeuEW $5.7 $19.8 $41.9 $21.5 $52.4 $92.7 $87.7 $104.8 $137.9 $136.6
29
Median
Gas C
Median Year of emission
2005 2015 2025 2035 2045 2055 2065 2075 2085 2095
Discounted to 2005
0% pure rate of time preference
NoEW $43.2 $51.6 $47.7 $34.6 $32.0 $35.5 $31.2 $27.4 $29.2 $22.5
AvEW $136.8 $133.2 $126.7 $93.9 $82.6 $87.6 $67.8 $61.3 $63.6 $50.0
WeuEW $651.6 $634.6 $603.6 $447.3 $393.4 $417.2 $322.7 $291.9 $302.9 $238.2
1% pure rate of time preference
NoEW $1.7 $4.6 $5.7 $2.7 $3.7 $4.3 $4.2 $3.7 $3.9 $2.7
AvEW $27.4 $28.7 $25.4 $15.0 $13.6 $15.0 $11.2 $9.0 $9.3 $6.7
WeuEW $130.6 $136.7 $120.8 $71.5 $64.8 $71.6 $53.2 $42.9 $44.5 $32.0
3% pure rate of time preference
NoEW -$9.1 -$5.7 -$3.1 -$2.3 -$1.1 -$0.5 -$0.3 -$0.1 $0.0 $0.0
AvEW -$7.3 -$4.0 -$1.4 -$2.0 -$0.9 -$0.1 $0.0 $0.1 $0.2 $0.1
WeuEW -$34.6 -$19.1 -$6.5 -$9.5 -$4.1 -$0.4 -$0.1 $0.4 $1.1 $0.5
Discounted to year of emission
0% pure rate of time preference
NoEW $43.2 $64.9 $76.8 $70.2 $76.6 $111.6 $118.6 $126.0 $150.2 $145.8
AvEW $136.8 $154.6 $170.2 $145.9 $147.6 $180.3 $161.7 $170.9 $209.0 $192.1
WeuEW $651.6 $763.6 $860.3 $741.1 $744.1 $886.0 $766.9 $775.4 $893.3 $770.6
1% pure rate of time preference
NoEW $1.7 $6.6 $11.5 $7.4 $14.8 $24.1 $27.0 $32.3 $47.5 $43.5
AvEW $27.4 $36.8 $41.5 $31.4 $36.2 $50.8 $48.4 $50.3 $68.1 $63.4
WeuEW $130.6 $181.7 $210.0 $159.6 $182.4 $250.3 $229.8 $228.4 $291.1 $253.7
3% pure rate of time preference
NoEW -$9.1 -$9.5 -$8.2 -$10.3 -$8.8 -$6.0 -$4.8 -$3.0 $1.2 -$0.5
AvEW -$7.3 -$6.3 -$3.3 -$7.5 -$5.0 -$0.7 -$0.2 $1.9 $8.2 $6.3
WeuEW -$34.6 -$30.9 -$16.8 -$38.3 -$25.4 -$3.5 -$1.2 $8.6 $35.2 $25.4
30
CH4
Best Guess
Gas CH4
Best Guess Year of emission
2005 2015 2025 2035 2045 2055 2065 2075 2085 2095
Discounted to 2005
0% pure rate of time preference
NoEW $364 $375 $382 $387 $388 $388 $386 $383 $380 $377
AvEW $894 $899 $899 $898 $893 $885 $874 $862 $850 $837
WeuEW $4,258 $4,281 $4,283 $4,277 $4,255 $4,213 $4,161 $4,106 $4,050 $3,986
1% pure rate of time preference
NoEW $165 $160 $152 $143 $133 $123 $113 $104 $95 $87
AvEW $422 $392 $362 $334 $306 $279 $254 $230 $209 $189
WeuEW $2,011 $1,867 $1,725 $1,590 $1,458 $1,330 $1,209 $1,097 $995 $900
3% pure rate of time preference
NoEW $61 $51 $41 $33 $26 $20 $15 $12 $9 $7
AvEW $167 $129 $99 $76 $59 $45 $34 $25 $19 $14
WeuEW $793 $614 $473 $364 $279 $212 $160 $121 $91 $69
Declining discount rate
$185 $182 $177 $171 $163 $155 $146 $137 $127 $117
Discounted to year of emission
0% pure rate of time preference
NoEW $364 $480 $622 $799 $1,013 $1,271 $1,596 $2,011 $2,518 $3,069
AvEW $894 $1,043 $1,208 $1,394 $1,597 $1,820 $2,082 $2,403 $2,793 $3,216
WeuEW $4,258 $5,152 $6,105 $7,086 $8,048 $8,950 $9,888 $10,904 $11,943 $12,894
1% pure rate of time preference
NoEW $165 $225 $300 $395 $512 $655 $837 $1,073 $1,365 $1,690
AvEW $422 $503 $593 $698 $815 $945 $1,099 $1,288 $1,521 $1,777
WeuEW $2,011 $2,482 $3,000 $3,550 $4,106 $4,647 $5,219 $5,846 $6,502 $7,127
3% pure rate of time preference
NoEW $61 $86 $119 $160 $212 $276 $357 $464 $598 $750
AvEW $167 $201 $241 $288 $341 $402 $473 $561 $670 $793
WeuEW $793 $993 $1,219 $1,465 $1,721 $1,975 $2,247 $2,547 $2,866 $3,178
Declining discount rate
$185 $240 $306 $386 $480 $590 $715 $855 $1,008 $1,170
31
Average
Gas CH4
Average Year of emission
2005 2015 2025 2035 2045 2055 2065 2075 2085 2095
Discounted to 2005
0% pure rate of time preference
NoEW $1,502 $893 $811 $984 $882 $1,434 $931 $750 $912 $746
AvEW $2,274 $2,083 $1,806 $2,773 $2,002 $2,166 $1,937 $1,603 $1,947 $1,596
WeuEW $10,829 $9,919 $8,598 $13,204 $9,533 $10,311 $9,222 $7,634 $9,268 $7,600
1% pure rate of time preference
NoEW $706 $403 $338 $369 $310 $493 $284 $211 $238 $177
AvEW $1,121 $958 $780 $984 $704 $729 $592 $454 $508 $377
WeuEW $5,335 $4,559 $3,712 $4,686 $3,351 $3,472 $2,816 $2,162 $2,416 $1,795
3% pure rate of time preference
NoEW $261 $138 $98 $86 $60 $84 $40 $25 $24 $14
AvEW $459 $331 $229 $211 $135 $122 $81 $53 $49 $30
WeuEW $2,186 $1,576 $1,089 $1,006 $642 $580 $388 $251 $234 $143
Discounted to year of emission
0% pure rate of time preference
NoEW $1,502 $1,142 $1,303 $2,025 $2,291 $4,016 $3,669 $3,630 $6,017 $5,396
AvEW $2,274 $2,419 $2,426 $4,309 $3,582 $4,459 $4,621 $4,474 $6,409 $6,143
WeuEW $10,829 $11,935 $12,255 $21,878 $18,033 $21,903 $21,915 $20,274 $27,334 $24,591
1% pure rate of time preference
NoEW $706 $570 $664 $1,023 $1,192 $2,248 $2,029 $2,053 $3,480 $3,141
AvEW $1,121 $1,228 $1,278 $2,061 $1,875 $2,470 $2,564 $2,543 $3,704 $3,552
WeuEW $5,335 $6,059 $6,456 $10,464 $9,438 $12,130 $12,160 $11,524 $15,796 $14,219
3% pure rate of time preference
NoEW $261 $237 $283 $424 $499 $1,008 $905 $940 $1,623 $1,476
AvEW $459 $517 $555 $797 $787 $1,101 $1,144 $1,165 $1,722 $1,654
WeuEW $2,186 $2,549 $2,804 $4,045 $3,960 $5,405 $5,426 $5,278 $7,342 $6,618
32
Average, 1% trimmed
Gas CH4
Average 1% Year of emission
2005 2015 2025 2035 2045 2055 2065 2075 2085 2095
Discounted to 2005
0% pure rate of time preference
NoEW $855 $779 $761 $834 $726 $793 $788 $669 $713 $649
AvEW $2,023 $1,817 $1,730 $1,885 $1,631 $1,754 $1,669 $1,414 $1,503 $1,409
WeuEW $9,631 $8,649 $8,236 $8,977 $7,764 $8,352 $7,948 $6,730 $7,156 $6,709
1% pure rate of time preference
NoEW $418 $359 $321 $319 $261 $264 $239 $188 $183 $155
AvEW $1,010 $860 $751 $730 $590 $587 $509 $401 $389 $335
WeuEW $4,809 $4,093 $3,575 $3,476 $2,808 $2,795 $2,423 $1,909 $1,853 $1,593
3% pure rate of time preference
NoEW $171 $126 $93 $76 $53 $45 $33 $22 $18 $13
AvEW $421 $305 $221 $173 $118 $98 $70 $47 $37 $27
WeuEW $2,004 $1,452 $1,051 $825 $560 $469 $335 $222 $179 $128
Discounted to year of emission
0% pure rate of time preference
NoEW $855 $994 $1,228 $1,707 $1,863 $2,502 $3,050 $3,176 $4,350 $4,767
AvEW $2,023 $2,109 $2,324 $2,929 $2,917 $3,612 $3,982 $3,944 $4,944 $5,421
WeuEW $9,631 $10,407 $11,739 $14,874 $14,685 $17,742 $18,888 $17,872 $21,105 $21,706
1% pure rate of time preference
NoEW $418 $506 $633 $879 $993 $1,366 $1,682 $1,797 $2,486 $2,773
AvEW $1,010 $1,102 $1,231 $1,529 $1,570 $1,988 $2,205 $2,245 $2,838 $3,153
WeuEW $4,809 $5,440 $6,218 $7,763 $7,907 $9,765 $10,462 $10,174 $12,115 $12,624
3% pure rate of time preference
NoEW $171 $215 $271 $374 $432 $609 $753 $826 $1,148 $1,302
AvEW $421 $476 $536 $653 $686 $888 $988 $1,031 $1,313 $1,479
WeuEW $2,004 $2,349 $2,705 $3,317 $3,455 $4,364 $4,686 $4,673 $5,603 $5,920
33
Average 5% trimmed
Gas CH4
Average 5% Year of emission
2005 2015 2025 2035 2045 2055 2065 2075 2085 2095
Discounted to 2005
0% pure rate of time preference
NoEW $724 $674 $665 $659 $616 $633 $625 $548 $592 $552
AvEW $1,749 $1,573 $1,542 $1,501 $1,392 $1,431 $1,373 $1,176 $1,278 $1,188
WeuEW $8,328 $7,491 $7,340 $7,148 $6,628 $6,811 $6,538 $5,598 $6,086 $5,657
1% pure rate of time preference
NoEW $359 $315 $287 $259 $226 $213 $190 $155 $154 $132
AvEW $897 $757 $677 $600 $513 $484 $421 $334 $331 $286
WeuEW $4,273 $3,605 $3,225 $2,856 $2,440 $2,303 $2,005 $1,589 $1,577 $1,360
3% pure rate of time preference
NoEW $150 $112 $85 $64 $47 $37 $27 $18 $15 $11
AvEW $383 $273 $202 $147 $104 $82 $59 $39 $32 $23
WeuEW $1,821 $1,302 $963 $701 $496 $390 $279 $185 $152 $110
Discounted to year of emission
0% pure rate of time preference
NoEW $724 $860 $1,073 $1,337 $1,569 $1,979 $2,444 $2,622 $3,559 $4,060
AvEW $1,749 $1,826 $2,071 $2,332 $2,490 $2,945 $3,275 $3,280 $4,203 $4,571
WeuEW $8,328 $9,013 $10,461 $11,843 $12,537 $14,469 $15,538 $14,867 $17,951 $18,303
1% pure rate of time preference
NoEW $359 $444 $565 $707 $856 $1,091 $1,350 $1,488 $2,047 $2,374
AvEW $897 $971 $1,110 $1,256 $1,365 $1,637 $1,825 $1,868 $2,415 $2,691
WeuEW $4,273 $4,791 $5,609 $6,377 $6,873 $8,045 $8,657 $8,467 $10,312 $10,774
3% pure rate of time preference
NoEW $150 $191 $245 $310 $382 $493 $607 $686 $951 $1,118
AvEW $383 $427 $491 $555 $608 $739 $822 $860 $1,120 $1,271
WeuEW $1,821 $2,105 $2,480 $2,820 $3,061 $3,633 $3,901 $3,897 $4,782 $5,088
34
Average 10% trimmed
Gas CH4
Average 10% Year of emission
2005 2015 2025 2035 2045 2055 2065 2075 2085 2095
Discounted to 2005
0% pure rate of time preference
NoEW $649 $602 $605 $590 $551 $558 $555 $479 $520 $487
AvEW $1,599 $1,425 $1,418 $1,341 $1,237 $1,265 $1,226 $1,037 $1,141 $1,054
WeuEW $7,612 $6,785 $6,753 $6,383 $5,892 $6,021 $5,835 $4,939 $5,434 $5,016
1% pure rate of time preference
NoEW $327 $285 $262 $233 $203 $188 $170 $136 $137 $117
AvEW $830 $693 $628 $540 $462 $431 $377 $295 $298 $253
WeuEW $3,954 $3,301 $2,992 $2,573 $2,198 $2,052 $1,797 $1,407 $1,420 $1,202
3% pure rate of time preference
NoEW $139 $102 $78 $58 $42 $33 $24 $16 $14 $10
AvEW $357 $254 $189 $134 $95 $74 $53 $35 $29 $20
WeuEW $1,702 $1,208 $900 $638 $451 $350 $252 $165 $138 $97
Discounted to year of emission
0% pure rate of time preference
NoEW $649 $768 $974 $1,192 $1,402 $1,723 $2,161 $2,278 $3,102 $3,556
AvEW $1,599 $1,654 $1,905 $2,082 $2,213 $2,603 $2,923 $2,893 $3,753 $4,053
WeuEW $7,612 $8,164 $9,626 $10,576 $11,145 $12,790 $13,868 $13,115 $16,027 $16,230
1% pure rate of time preference
NoEW $327 $401 $515 $634 $767 $957 $1,200 $1,295 $1,796 $2,080
AvEW $830 $889 $1,030 $1,131 $1,229 $1,459 $1,635 $1,654 $2,173 $2,379
WeuEW $3,954 $4,387 $5,203 $5,746 $6,191 $7,168 $7,759 $7,496 $9,281 $9,526
3% pure rate of time preference
NoEW $139 $174 $226 $280 $343 $436 $543 $599 $841 $983
AvEW $357 $396 $459 $505 $553 $664 $743 $767 $1,015 $1,126
WeuEW $1,702 $1,954 $2,318 $2,567 $2,783 $3,262 $3,523 $3,475 $4,335 $4,510
35
Median
Gas CH4
Median Year of emission
2005 2015 2025 2035 2045 2055 2065 2075 2085 2095
Discounted to 2005
0% pure rate of time preference
NoEW $429 $395 $406 $388 $333 $341 $329 $272 $304 $264
AvEW $1,099 $993 $1,027 $886 $784 $752 $772 $631 $674 $588
WeuEW $5,236 $4,730 $4,893 $4,220 $3,735 $3,580 $3,674 $3,006 $3,210 $2,797
1% pure rate of time preference
NoEW $227 $194 $182 $161 $124 $116 $103 $80 $80 $63
AvEW $599 $499 $471 $369 $299 $262 $244 $188 $181 $141
WeuEW $2,853 $2,378 $2,244 $1,759 $1,426 $1,247 $1,160 $893 $863 $674
3% pure rate of time preference
NoEW $102 $71 $56 $41 $26 $21 $15 $10 $8 $5
AvEW $275 $183 $141 $95 $61 $46 $34 $22 $18 $11
WeuEW $1,308 $873 $673 $454 $292 $218 $164 $106 $85 $54
Discounted to year of emission
0% pure rate of time preference
NoEW $429 $508 $656 $776 $821 $1,056 $1,276 $1,309 $1,757 $1,887
AvEW $1,099 $1,153 $1,380 $1,377 $1,402 $1,547 $1,842 $1,759 $2,213 $2,266
WeuEW $5,236 $5,691 $6,973 $6,993 $7,065 $7,605 $8,732 $7,982 $9,467 $9,052
1% pure rate of time preference
NoEW $227 $271 $362 $427 $460 $579 $698 $760 $1,030 $1,065
AvEW $599 $640 $772 $774 $797 $886 $1,055 $1,050 $1,319 $1,333
WeuEW $2,853 $3,161 $3,902 $3,928 $4,015 $4,356 $5,008 $4,757 $5,644 $5,338
3% pure rate of time preference
NoEW $102 $121 $163 $199 $215 $269 $331 $361 $494 $508
AvEW $275 $286 $343 $360 $357 $413 $483 $491 $624 $623
WeuEW $1,308 $1,412 $1,734 $1,827 $1,799 $2,030 $2,294 $2,228 $2,667 $2,496
36
N2O
Best Guess
Gas N2O
BestGuess Year of emission
2005 2015 2025 2035 2045 2055 2065 2075 2085 2095
Discounted to 2005
0% pure rate of time preference
NoEW $27,748 $27,684 $27,467 $27,105 $26,607 $25,985 $25,245 $24,398 $23,451 $22,412
AvEW $63,238 $62,615 $61,741 $60,611 $59,230 $57,608 $55,761 $53,704 $51,459 $49,043
WeuEW $301,184 $298,217 $294,052 $288,672 $282,094 $274,372 $265,571 $255,778 $245,083 $233,578
1% pure rate of time preference
NoEW $7,984 $7,532 $7,044 $6,537 $6,023 $5,515 $5,020 $4,542 $4,087 $3,655
AvEW $18,567 $17,217 $15,890 $14,590 $13,326 $12,106 $10,940 $9,835 $8,797 $7,827
WeuEW $88,427 $82,001 $75,681 $69,490 $63,466 $57,658 $52,105 $46,843 $41,897 $37,280
3% pure rate of time preference
NoEW $1,637 $1,338 $1,076 $855 $671 $522 $403 $309 $235 $178
AvEW $4,034 $3,164 $2,470 $1,917 $1,479 $1,133 $863 $653 $492 $369
WeuEW $19,212 $15,069 $11,766 $9,132 $7,042 $5,396 $4,109 $3,111 $2,343 $1,755
Declining discount rate
$9,898 $9,480 $9,010 $8,499 $7,957 $7,393 $6,818 $6,239 $5,664 $5,105
Discounted to year of emission
0% pure rate of time preference
NoEW $27,748 $35,461 $44,793 $56,136 $69,578 $85,434 $104,740 $128,418 $155,752 $183,273
AvEW $63,238 $72,665 $82,909 $94,104 $105,864 $118,491 $132,855 $149,657 $169,030 $188,454
WeuEW $301,184 $358,829 $419,107 $478,304 $533,597 $582,806 $631,114 $679,230 $722,792 $755,691
1% pure rate of time preference
NoEW $7,984 $10,623 $13,938 $18,100 $23,205 $29,438 $37,258 $47,135 $58,978 $71,611
AvEW $18,567 $22,071 $26,037 $30,533 $35,461 $40,952 $47,355 $55,002 $64,054 $73,650
WeuEW $88,427 $108,990 $131,619 $155,190 $178,738 $201,425 $224,953 $249,631 $273,903 $295,333
3% pure rate of time preference
NoEW $1,637 $2,281 $3,118 $4,195 $5,549 $7,245 $9,421 $12,232 $15,700 $19,556
AvEW $4,034 $4,934 $5,991 $7,226 $8,621 $10,217 $12,111 $14,412 $17,192 $20,254
WeuEW $19,212 $24,367 $30,287 $36,728 $43,454 $50,251 $57,533 $65,408 $73,517 $81,216
Declining discount rate
$9,898 $12,035 $14,513 $17,347 $20,536 $24,062 $27,876 $31,905 $36,070 $40,300
37
Average
Gas N2O
Average Year of emission
2005 2015 2025 2035 2045 2055 2065 2075 2085 2095
Discounted to 2005
0% pure rate of time preference
NoEW $57,775 $69,395 $54,626 $62,067 $57,331 $77,796 $57,038 $58,143 $38,207 $53,966
AvEW $122,603 $153,136 $125,094 $124,643 $103,773 $165,541 $96,086 $110,565 $73,507 $116,720
WeuEW $583,743 $729,083 $595,598 $593,443 $494,070 $788,208 $457,487 $526,398 $349,987 $555,670
1% pure rate of time preference
NoEW $17,394 $19,153 $14,594 $15,097 $13,150 $16,550 $11,579 $11,122 $6,948 $9,116
AvEW $39,082 $42,544 $33,888 $31,380 $25,084 $35,137 $20,482 $21,478 $13,491 $19,603
WeuEW $186,076 $202,548 $161,342 $149,404 $119,425 $167,298 $97,518 $102,256 $64,236 $93,322
3% pure rate of time preference
NoEW $3,967 $3,560 $2,399 $2,007 $1,504 $1,530 $967 $790 $431 $468
AvEW $9,383 $8,019 $5,579 $4,297 $3,025 $3,240 $1,788 $1,532 $834 $984
WeuEW $44,673 $38,176 $26,560 $20,457 $14,403 $15,428 $8,514 $7,292 $3,970 $4,685
Discounted to year of emission
0% pure rate of time preference
NoEW $57,775 $88,568 $87,648 $124,917 $139,766 $248,511 $203,992 $264,740 $218,605 $433,618
AvEW $122,603 $177,763 $168,059 $193,648 $185,637 $340,780 $229,166 $308,557 $241,752 $449,266
WeuEW $583,743 $877,274 $848,903 $983,298 $934,579 $1,674,315 $1,087,228 $1,397,949 $1,032,221 $1,797,832
1% pure rate of time preference
NoEW $17,394 $26,987 $28,647 $41,114 $48,149 $86,778 $76,380 $102,731 $88,545 $178,695
AvEW $39,082 $54,555 $55,553 $65,713 $66,812 $118,963 $88,750 $120,291 $98,360 $184,756
WeuEW $186,076 $269,216 $280,596 $333,663 $336,340 $584,460 $421,028 $544,960 $419,960 $739,337
3% pure rate of time preference
NoEW $3,967 $6,085 $6,957 $9,813 $12,102 $21,227 $20,836 $28,784 $26,128 $52,425
AvEW $9,383 $12,510 $13,537 $16,204 $17,655 $29,246 $25,129 $33,847 $29,182 $54,168
WeuEW $44,673 $61,733 $68,372 $82,273 $88,871 $143,675 $119,203 $153,329 $124,588 $216,762
38
Average, 1% trimmed
Gas N2O
Average 1% Year of emission
2005 2015 2025 2035 2045 2055 2065 2075 2085 2095
Discounted to 2005
0% pure rate of time preference
NoEW $52,616 $57,395 $49,945 $52,906 $48,913 $54,037 $46,339 $46,246 $34,336 $38,339
AvEW $113,404 $125,468 $105,087 $106,798 $93,832 $116,328 $86,150 $93,686 $68,083 $79,572
WeuEW $539,941 $597,367 $500,332 $508,477 $446,735 $553,858 $410,174 $446,039 $324,167 $378,867
1% pure rate of time preference
NoEW $16,219 $16,434 $13,496 $13,112 $11,584 $11,968 $9,651 $8,956 $6,244 $6,471
AvEW $36,771 $36,271 $29,193 $27,446 $23,062 $26,186 $18,471 $18,330 $12,556 $13,521
WeuEW $175,068 $172,694 $138,989 $130,675 $109,799 $124,674 $87,943 $87,266 $59,786 $64,379
3% pure rate of time preference
NoEW $3,765 $3,141 $2,232 $1,793 $1,384 $1,203 $832 $649 $388 $336
AvEW $8,980 $7,070 $4,970 $3,878 $2,836 $2,608 $1,628 $1,324 $780 $697
WeuEW $42,753 $33,661 $23,662 $18,462 $13,502 $12,415 $7,749 $6,303 $3,714 $3,319
Discounted to year of emission
0% pure rate of time preference
NoEW $52,616 $72,779 $80,318 $106,094 $121,278 $171,276 $171,760 $220,508 $197,208 $280,013
AvEW $113,404 $145,644 $141,183 $165,923 $167,859 $239,505 $205,472 $261,408 $223,888 $306,139
WeuEW $539,941 $718,787 $713,122 $842,515 $845,040 $1,176,512 $974,792 $1,184,535 $956,070 $1,225,808
1% pure rate of time preference
NoEW $16,219 $23,028 $26,507 $35,477 $43,137 $62,958 $65,648 $86,216 $80,269 $115,861
AvEW $36,771 $46,508 $47,856 $57,469 $61,427 $88,668 $80,037 $102,638 $91,532 $127,385
WeuEW $175,068 $229,536 $241,721 $291,836 $309,231 $435,557 $379,688 $465,067 $390,867 $510,036
3% pure rate of time preference
NoEW $3,765 $5,352 $6,471 $8,719 $11,247 $16,709 $18,259 $24,473 $23,850 $34,668
AvEW $8,980 $11,029 $12,060 $14,623 $16,551 $23,536 $22,872 $29,250 $27,294 $38,355
WeuEW $42,753 $54,433 $60,912 $74,252 $83,315 $115,611 $108,498 $132,526 $116,548 $153,556
39
Average 5% trimmed
Gas N2O
Average 5% Year of emission
2005 2015 2025 2035 2045 2055 2065 2075 2085 2095
Discounted to 2005
0% pure rate of time preference
NoEW $45,586 $46,188 $41,891 $42,170 $39,373 $38,558 $35,587 $38,047 $29,237 $32,242
AvEW $97,191 $97,619 $88,700 $87,144 $80,086 $81,208 $72,391 $75,624 $58,602 $64,807
WeuEW $462,755 $464,796 $422,325 $414,911 $381,301 $386,660 $344,678 $360,053 $279,034 $308,571
1% pure rate of time preference
NoEW $14,231 $13,473 $11,417 $10,727 $9,571 $8,647 $7,540 $7,426 $5,382 $5,482
AvEW $32,160 $29,905 $24,978 $23,041 $19,836 $18,648 $15,674 $14,968 $10,858 $11,109
WeuEW $153,123 $142,387 $118,928 $109,706 $94,444 $88,787 $74,629 $71,264 $51,700 $52,895
3% pure rate of time preference
NoEW $3,382 $2,716 $1,935 $1,521 $1,177 $895 $671 $544 $338 $288
AvEW $8,117 $6,261 $4,349 $3,365 $2,471 $1,954 $1,401 $1,101 $680 $579
WeuEW $38,644 $29,812 $20,708 $16,020 $11,767 $9,303 $6,670 $5,240 $3,238 $2,755
Discounted to year of emission
0% pure rate of time preference
NoEW $45,586 $58,557 $67,163 $84,494 $98,108 $118,090 $134,081 $176,579 $166,767 $224,872
AvEW $97,191 $113,312 $119,160 $135,380 $143,257 $167,176 $172,639 $210,985 $192,702 $249,315
WeuEW $462,755 $559,269 $601,940 $687,482 $721,267 $821,347 $819,136 $956,183 $822,955 $998,363
1% pure rate of time preference
NoEW $14,231 $18,903 $22,359 $29,021 $35,589 $43,838 $51,936 $69,768 $68,198 $94,085
AvEW $32,160 $38,344 $40,946 $48,245 $52,830 $63,137 $67,909 $83,799 $79,148 $104,653
WeuEW $153,123 $189,252 $206,832 $245,006 $265,985 $310,183 $322,205 $379,787 $338,000 $419,055
3% pure rate of time preference
NoEW $3,382 $4,631 $5,587 $7,382 $9,518 $12,061 $14,920 $20,110 $20,428 $28,575
AvEW $8,117 $9,768 $10,553 $12,687 $14,422 $17,635 $19,685 $24,315 $23,792 $31,833
WeuEW $38,644 $48,209 $53,307 $64,428 $72,607 $86,636 $93,396 $110,192 $101,606 $127,467
40
Average 10% trimmed
Gas N2O
Average 10% Year of emission
2005 2015 2025 2035 2045 2055 2065 2075 2085 2095
Discounted to 2005
0% pure rate of time preference
NoEW $40,500 $40,973 $36,578 $37,314 $33,995 $33,475 $31,587 $33,301 $26,206 $28,556
AvEW $87,578 $87,236 $77,450 $77,496 $70,506 $70,360 $64,655 $66,891 $52,504 $57,364
WeuEW $416,995 $415,370 $368,778 $368,987 $335,707 $335,017 $307,843 $318,494 $250,002 $273,138
1% pure rate of time preference
NoEW $12,861 $12,196 $10,135 $9,584 $8,287 $7,583 $6,791 $6,548 $4,837 $4,875
AvEW $29,111 $27,115 $22,151 $20,645 $17,555 $16,328 $14,146 $13,280 $9,792 $9,870
WeuEW $138,610 $129,104 $105,471 $98,298 $83,585 $77,743 $67,353 $63,233 $46,627 $46,996
3% pure rate of time preference
NoEW $3,110 $2,496 $1,745 $1,380 $1,030 $795 $611 $483 $305 $256
AvEW $7,462 $5,788 $3,922 $3,052 $2,205 $1,732 $1,280 $978 $618 $517
WeuEW $35,530 $27,558 $18,674 $14,533 $10,499 $8,248 $6,093 $4,657 $2,942 $2,462
Discounted to year of emission
0% pure rate of time preference
NoEW $40,500 $51,962 $58,504 $74,523 $84,264 $101,964 $118,413 $155,202 $148,480 $197,416
AvEW $87,578 $101,257 $104,043 $120,385 $126,103 $144,832 $154,191 $186,585 $172,628 $220,663
WeuEW $416,995 $499,797 $525,618 $611,389 $635,020 $711,644 $731,599 $845,806 $737,331 $883,712
1% pure rate of time preference
NoEW $12,861 $17,106 $19,797 $25,876 $30,741 $38,277 $46,505 $61,416 $60,789 $82,862
AvEW $29,111 $34,766 $36,309 $43,226 $46,746 $55,276 $61,287 $74,341 $71,374 $92,969
WeuEW $138,610 $171,598 $183,429 $219,530 $235,403 $271,599 $290,793 $336,982 $304,837 $372,316
3% pure rate of time preference
NoEW $3,110 $4,254 $5,030 $6,669 $8,318 $10,646 $13,495 $17,716 $18,260 $25,235
AvEW $7,462 $9,029 $9,516 $11,509 $12,864 $15,632 $17,979 $21,601 $21,620 $28,441
WeuEW $35,530 $44,563 $48,071 $58,447 $64,782 $76,805 $85,308 $97,919 $92,337 $113,898
41
Median
Gas N2O
Median Year of emission
2005 2015 2025 2035 2045 2055 2065 2075 2085 2095
Discounted to 2005
0% pure rate of time preference
NoEW $24,868 $28,113 $21,735 $22,856 $21,436 $20,926 $19,414 $19,812 $16,573 $16,603
AvEW $56,688 $59,946 $49,749 $48,320 $45,219 $43,728 $38,149 $40,414 $34,166 $34,758
WeuEW $269,918 $285,437 $236,873 $230,132 $215,167 $208,230 $181,695 $192,464 $162,710 $165,580
1% pure rate of time preference
NoEW $8,180 $8,517 $6,106 $6,088 $5,215 $4,790 $4,058 $3,922 $3,064 $2,920
AvEW $19,581 $19,135 $14,642 $13,516 $11,403 $10,381 $8,466 $8,223 $6,458 $6,044
WeuEW $93,240 $91,119 $69,723 $64,373 $54,297 $49,436 $40,317 $39,151 $30,754 $28,790
3% pure rate of time preference
NoEW $2,158 $1,831 $1,128 $934 $672 $528 $364 $300 $199 $155
AvEW $5,440 $4,291 $2,757 $2,119 $1,448 $1,137 $770 $619 $404 $315
WeuEW $25,912 $20,437 $13,136 $10,093 $6,898 $5,415 $3,667 $2,948 $1,927 $1,503
Discounted to year of emission
0% pure rate of time preference
NoEW $24,868 $35,940 $34,672 $45,096 $52,355 $61,664 $68,647 $87,158 $95,260 $110,818
AvEW $56,688 $69,577 $66,802 $75,040 $80,849 $90,005 $90,917 $112,637 $112,331 $133,665
WeuEW $269,918 $343,454 $337,614 $381,313 $407,005 $442,325 $431,782 $511,075 $479,862 $535,679
1% pure rate of time preference
NoEW $8,180 $11,899 $11,880 $16,427 $19,108 $23,569 $27,060 $34,381 $38,308 $47,239
AvEW $19,581 $24,532 $23,998 $28,279 $30,351 $35,108 $36,646 $46,034 $47,045 $56,927
WeuEW $93,240 $121,110 $121,256 $143,760 $152,916 $172,700 $174,059 $208,640 $201,045 $228,049
3% pure rate of time preference
NoEW $2,158 $3,081 $3,236 $4,467 $5,270 $6,672 $7,859 $10,392 $11,564 $14,697
AvEW $5,440 $6,691 $6,686 $7,983 $8,442 $10,255 $10,806 $13,671 $14,118 $17,370
WeuEW $25,912 $33,047 $33,814 $40,592 $42,561 $50,427 $51,340 $61,987 $60,455 $69,540
42
SF6
Best Guess
Gas SF6
Best Guess Year of emission
2005 2015 2025 2035 2045 2055 2065 2075 2085 2095
Discounted to 2005
0% pure rate of time preference
NoEW $1,917 $1,857 $1,793 $1,724 $1,650 $1,574 $1,494 $1,411 $1,326 $1,240
AvEW $4,275 $4,127 $3,971 $3,807 $3,635 $3,458 $3,274 $3,087 $2,895 $2,702
WeuEW $20,361 $19,656 $18,911 $18,130 $17,314 $16,468 $15,595 $14,700 $13,789 $12,867
1% pure rate of time preference
NoEW $419 $390 $361 $332 $303 $275 $249 $223 $199 $177
AvEW $947 $872 $799 $729 $662 $597 $536 $479 $426 $376
WeuEW $4,510 $4,152 $3,806 $3,472 $3,151 $2,845 $2,555 $2,283 $2,028 $1,792
3% pure rate of time preference
NoEW $63 $51 $42 $33 $26 $20 $16 $12 $9 $7
AvEW $151 $119 $94 $73 $57 $44 $34 $26 $20 $15
WeuEW $719 $568 $447 $350 $272 $210 $161 $123 $93 $70
Declining discount rate
$545 $513 $480 $446 $412 $379 $345 $313 $281 $251
Discounted to year of emission
0% pure rate of time preference
NoEW $1,917 $2,380 $2,925 $3,572 $4,319 $5,179 $6,203 $7,435 $8,818 $10,149
AvEW $4,275 $4,789 $5,332 $5,910 $6,498 $7,112 $7,801 $8,601 $9,510 $10,381
WeuEW $20,361 $23,650 $26,954 $30,040 $32,751 $34,980 $37,060 $39,037 $40,667 $41,629
1% pure rate of time preference
NoEW $419 $551 $715 $919 $1,169 $1,471 $1,847 $2,318 $2,878 $3,465
AvEW $947 $1,118 $1,309 $1,525 $1,760 $2,020 $2,322 $2,680 $3,101 $3,540
WeuEW $4,510 $5,519 $6,619 $7,753 $8,873 $9,938 $11,031 $12,164 $13,258 $14,194
3% pure rate of time preference
NoEW $63 $88 $120 $163 $217 $284 $372 $486 $627 $785
AvEW $151 $186 $228 $277 $333 $397 $474 $568 $682 $808
WeuEW $719 $919 $1,151 $1,407 $1,677 $1,953 $2,252 $2,579 $2,917 $3,242
Declining discount rate
$545 $639 $747 $868 $1,003 $1,150 $1,308 $1,474 $1,645 $1,818
43
Average
Gas SF6
Average Year of emission
2005 2015 2025 2035 2045 2055 2065 2075 2085 2095
Discounted to 2005
0% pure rate of time preference
NoEW $3,764 $18,663 $4,339 $2,948 $3,561 $3,046 $4,025 $2,483 $3,068 $3,135
AvEW $7,611 $53,710 $9,410 $5,825 $7,864 $5,707 $6,765 $4,719 $6,635 $5,289
WeuEW $36,235 $255,533 $44,794 $27,732 $37,442 $27,171 $32,207 $22,470 $31,583 $25,180
1% pure rate of time preference
NoEW $884 $4,074 $883 $596 $678 $552 $690 $408 $467 $443
AvEW $1,889 $11,485 $1,971 $1,225 $1,505 $1,077 $1,193 $797 $1,008 $766
WeuEW $8,994 $54,644 $9,381 $5,834 $7,165 $5,127 $5,679 $3,795 $4,800 $3,647
3% pure rate of time preference
NoEW $152 $572 $106 $65 $62 $44 $46 $24 $23 $18
AvEW $346 $1,575 $241 $140 $137 $89 $83 $48 $49 $32
WeuEW $1,648 $7,493 $1,147 $667 $652 $423 $394 $230 $231 $153
Discounted to year of emission
0% pure rate of time preference
NoEW $3,764 $24,594 $6,986 $5,830 $8,988 $9,218 $14,570 $11,458 $18,965 $22,298
AvEW $7,611 $62,379 $12,646 $9,051 $14,068 $11,750 $16,135 $13,166 $21,834 $20,372
WeuEW $36,235 $307,480 $63,846 $45,950 $70,826 $57,717 $76,541 $59,672 $93,151 $81,472
1% pure rate of time preference
NoEW $884 $5,920 $1,743 $1,599 $2,560 $2,783 $4,575 $3,838 $6,417 $7,775
AvEW $1,889 $14,735 $3,231 $2,566 $4,008 $3,647 $5,169 $4,462 $7,356 $7,224
WeuEW $8,994 $72,631 $16,315 $13,029 $20,178 $17,913 $24,518 $20,222 $31,383 $28,893
3% pure rate of time preference
NoEW $152 $1,007 $310 $316 $509 $590 $1,000 $902 $1,491 $1,850
AvEW $346 $2,458 $585 $528 $799 $802 $1,163 $1,068 $1,703 $1,766
WeuEW $1,648 $12,118 $2,953 $2,683 $4,021 $3,939 $5,516 $4,841 $7,264 $7,063
44
Average, 1% trimmed
Gas SF6
Average 1% Year of emission
2005 2015 2025 2035 2045 2055 2065 2075 2085 2095
Discounted to 2005
0% pure rate of time preference
NoEW $3,455 $3,685 $3,554 $2,571 $3,088 $2,626 $2,643 $2,132 $2,313 $1,946
AvEW $6,999 $7,486 $6,959 $5,259 $6,376 $5,018 $5,280 $4,169 $4,513 $3,653
WeuEW $33,324 $35,640 $33,133 $25,039 $30,359 $23,890 $25,137 $19,849 $21,488 $17,390
1% pure rate of time preference
NoEW $814 $819 $731 $526 $592 $482 $465 $356 $358 $288
AvEW $1,745 $1,759 $1,528 $1,124 $1,257 $951 $947 $709 $709 $548
WeuEW $8,306 $8,373 $7,275 $5,350 $5,987 $4,528 $4,509 $3,376 $3,373 $2,609
3% pure rate of time preference
NoEW $142 $120 $90 $59 $55 $39 $33 $22 $18 $13
AvEW $324 $274 $200 $130 $120 $80 $67 $43 $36 $24
WeuEW $1,545 $1,306 $952 $620 $570 $379 $321 $207 $170 $115
Discounted to year of emission
0% pure rate of time preference
NoEW $3,455 $4,672 $5,630 $5,137 $7,667 $7,999 $9,857 $10,011 $13,562 $13,299
AvEW $6,999 $8,690 $9,349 $8,171 $11,405 $10,330 $12,594 $11,629 $14,845 $14,059
WeuEW $33,324 $42,885 $47,224 $41,488 $57,428 $50,747 $59,738 $52,712 $63,374 $56,267
1% pure rate of time preference
NoEW $814 $1,149 $1,422 $1,423 $2,210 $2,437 $3,178 $3,379 $4,691 $4,863
AvEW $1,745 $2,255 $2,505 $2,353 $3,349 $3,220 $4,104 $3,969 $5,167 $5,165
WeuEW $8,306 $11,129 $12,652 $11,948 $16,861 $15,821 $19,466 $17,991 $22,055 $20,669
3% pure rate of time preference
NoEW $142 $206 $260 $285 $448 $526 $724 $801 $1,125 $1,242
AvEW $324 $428 $485 $491 $698 $719 $947 $960 $1,252 $1,326
WeuEW $1,545 $2,112 $2,452 $2,494 $3,516 $3,530 $4,493 $4,353 $5,346 $5,308
45
Average 5% trimmed
Gas SF6
Average 5% Year of emission
2005 2015 2025 2035 2045 2055 2065 2075 2085 2095
Discounted to 2005
0% pure rate of time preference
NoEW $2,893 $2,975 $2,658 $2,166 $2,420 $2,102 $2,106 $1,806 $1,757 $1,589
AvEW $5,842 $6,270 $5,234 $4,350 $4,900 $4,113 $4,268 $3,556 $3,554 $3,024
WeuEW $27,815 $29,851 $24,922 $20,713 $23,331 $19,582 $20,323 $16,932 $16,922 $14,400
1% pure rate of time preference
NoEW $693 $685 $578 $450 $470 $393 $378 $302 $277 $236
AvEW $1,490 $1,492 $1,199 $948 $983 $794 $777 $605 $564 $456
WeuEW $7,094 $7,104 $5,709 $4,511 $4,682 $3,783 $3,699 $2,883 $2,686 $2,173
3% pure rate of time preference
NoEW $124 $104 $76 $51 $45 $33 $27 $18 $14 $10
AvEW $287 $239 $168 $113 $96 $69 $57 $37 $29 $20
WeuEW $1,369 $1,137 $798 $539 $458 $326 $269 $178 $139 $97
Discounted to year of emission
0% pure rate of time preference
NoEW $2,893 $3,777 $4,232 $4,294 $5,947 $6,328 $7,865 $8,350 $10,029 $10,585
AvEW $5,842 $7,278 $7,032 $6,758 $8,764 $8,466 $10,180 $9,918 $11,687 $11,636
WeuEW $27,815 $35,918 $35,522 $34,321 $44,132 $41,596 $48,298 $44,965 $49,908 $46,591
1% pure rate of time preference
NoEW $693 $961 $1,127 $1,210 $1,733 $1,964 $2,581 $2,829 $3,518 $3,894
AvEW $1,490 $1,913 $1,966 $1,984 $2,619 $2,690 $3,366 $3,389 $4,112 $4,300
WeuEW $7,094 $9,442 $9,929 $10,075 $13,187 $13,215 $15,970 $15,362 $17,558 $17,216
3% pure rate of time preference
NoEW $124 $178 $220 $248 $363 $440 $603 $678 $869 $1,005
AvEW $287 $373 $407 $427 $562 $619 $794 $824 $1,020 $1,116
WeuEW $1,369 $1,839 $2,055 $2,167 $2,828 $3,039 $3,769 $3,735 $4,355 $4,467
46
Average 10% trimmed
Gas SF6
Average 10% Year of emission
2005 2015 2025 2035 2045 2055 2065 2075 2085 2095
Discounted to 2005
0% pure rate of time preference
NoEW $2,570 $2,574 $2,323 $1,914 $2,073 $1,845 $1,825 $1,605 $1,516 $1,379
AvEW $5,194 $5,519 $4,609 $3,867 $4,178 $3,646 $3,706 $3,197 $3,076 $2,673
WeuEW $24,732 $26,280 $21,944 $18,411 $19,894 $17,359 $17,647 $15,225 $14,645 $12,728
1% pure rate of time preference
NoEW $623 $595 $512 $401 $407 $347 $329 $270 $241 $206
AvEW $1,345 $1,327 $1,069 $848 $848 $704 $678 $544 $493 $405
WeuEW $6,402 $6,319 $5,088 $4,036 $4,040 $3,353 $3,226 $2,592 $2,350 $1,926
3% pure rate of time preference
NoEW $114 $93 $69 $46 $40 $29 $24 $17 $13 $9
AvEW $265 $215 $153 $102 $85 $61 $50 $34 $26 $18
WeuEW $1,263 $1,024 $727 $488 $404 $290 $237 $160 $123 $86
Discounted to year of emission
0% pure rate of time preference
NoEW $2,570 $3,269 $3,682 $3,779 $5,103 $5,581 $6,797 $7,388 $8,586 $9,188
AvEW $5,194 $6,407 $6,191 $6,006 $7,472 $7,505 $8,839 $8,918 $10,113 $10,284
WeuEW $24,732 $31,621 $31,276 $30,505 $37,632 $36,873 $41,939 $40,432 $43,194 $41,180
1% pure rate of time preference
NoEW $623 $835 $996 $1,074 $1,496 $1,738 $2,236 $2,508 $3,039 $3,378
AvEW $1,345 $1,702 $1,752 $1,775 $2,259 $2,384 $2,935 $3,047 $3,597 $3,811
WeuEW $6,402 $8,399 $8,848 $9,013 $11,377 $11,715 $13,928 $13,814 $15,362 $15,259
3% pure rate of time preference
NoEW $114 $159 $199 $223 $317 $389 $525 $606 $758 $874
AvEW $265 $336 $370 $386 $495 $550 $700 $744 $903 $996
WeuEW $1,263 $1,656 $1,870 $1,962 $2,492 $2,703 $3,323 $3,371 $3,857 $3,986
47
Median
Gas SF6
Median Year of emission
2005 2015 2025 2035 2045 2055 2065 2075 2085 2095
Discounted to 2005
0% pure rate of time preference
NoEW $1,551 $1,454 $1,500 $1,235 $1,180 $1,150 $1,117 $1,000 $940 $861
AvEW $3,218 $3,142 $3,103 $2,552 $2,435 $2,336 $2,269 $1,970 $1,816 $1,706
WeuEW $15,319 $14,960 $14,772 $12,153 $11,592 $11,118 $10,805 $9,380 $8,648 $8,128
1% pure rate of time preference
NoEW $391 $360 $339 $260 $235 $221 $202 $170 $154 $128
AvEW $890 $812 $759 $570 $499 $452 $416 $349 $304 $262
WeuEW $4,239 $3,865 $3,619 $2,715 $2,376 $2,149 $1,983 $1,662 $1,447 $1,247
3% pure rate of time preference
NoEW $76 $60 $49 $31 $25 $19 $15 $11 $8 $6
AvEW $188 $144 $111 $73 $55 $38 $32 $23 $16 $12
WeuEW $897 $684 $530 $346 $260 $182 $152 $110 $77 $57
Discounted to year of emission
0% pure rate of time preference
NoEW $1,551 $1,834 $2,379 $2,426 $2,917 $3,445 $4,096 $4,362 $5,255 $5,593
AvEW $3,218 $3,648 $4,169 $3,961 $4,358 $4,814 $5,415 $5,489 $5,963 $6,553
WeuEW $15,319 $18,001 $21,056 $20,137 $21,927 $23,620 $25,678 $24,910 $25,505 $26,295
1% pure rate of time preference
NoEW $391 $500 $660 $695 $881 $1,072 $1,389 $1,559 $1,909 $2,084
AvEW $890 $1,041 $1,244 $1,194 $1,331 $1,530 $1,800 $1,955 $2,217 $2,468
WeuEW $4,239 $5,137 $6,293 $6,064 $6,693 $7,509 $8,559 $8,856 $9,461 $9,882
3% pure rate of time preference
NoEW $76 $102 $139 $150 $194 $243 $324 $392 $485 $548
AvEW $188 $224 $270 $274 $318 $345 $448 $511 $567 $660
WeuEW $897 $1,106 $1,365 $1,391 $1,606 $1,698 $2,128 $2,320 $2,429 $2,642