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Summary of Global Climate Related Facts

This is an html version of the appendix of Welch-Cornell (2020): Global Climate Change. It has been copied and adapted by hand and therefore may contain errors. Please refer to the book itself in case of doubt. Also, please bring any errors to our attention ASAP.

01: Population

Fig 3: Population (in billion)
	1960	2020		2100e	Δ	%Δ
OECD	815	1,369	≈	1,400	+31	2%
USA	187	331	↗	434	+103	31%
EU27	356	445	↘	364	–18	–81%
Asia	1,705	4,641	≈	4,720	+79	2%
China	660	1,439	↓	1,065	–374	–26%
Other Far East	963	2,206	↘	1,826	–380	–17%
South Asia	517	1,605	≈	1,689	+84	5%
India	451	1,380	≈	1,447	+67	5%
Africa	203	1,341	↑↑	4,280	+2,939	219%
Sub-Sahara	220	1,094	↑↑	3,776	+2,682	245%
Nigeria	45	206	↑↑	733	+527	256%
World Total	3,035	7,795	↑↑	10,875	+3,080	40%

Primary Data Source: Worldbank and United Nations.

02: Primary Energy (PE)

Fig 9-8: PE By Region (ca 2022)
	Popln	Total	pPpD
OECD	1.38	71 PWh	141 KWh
USA	0.33	28 PWh	232 KWh
Europe	0.60	24 PWh	109 KWh
Not OECD	6.50	116 PWh	49 KWh
China	1.45	48 PWh	90 KWh
India	1.41	12 PWh	23 KWh
Other Asia	1.18	14 PWh	32 KWh
Africa	1.37	7 PWh	14 KWh
Sub-Sahara	1.04	2 PWh	5 KWh
USSR (CIS)	0.25	11 PWh	121 KWh
Mid-East	0.26	10 PWh	111 KWh
Latin America	0.52	8 PWh	41 KWh
World	7.88	187 PWh	65 KWh

Primary data source is US EIA. Population is in billions. pPpD is per Person per Day. USSR, Mid-East and Latin America are from British Petroleum (BP).

Tbl 5: Energy Purpose
	USA	World
Home/Work	40%	30%
Transport	30%	20%
Industry	30%	50%

Primary Source: NAS.

Data Disagreements
BP	EIA¹ HDB	EIA² IEO
162 PWh	186 PWh	173 PWh

All three estimates are for total primary energy consumption for the world in 2019. Our World in Data also uses the BP data. The first EIA number is from the Historical Data Browser, the second is from the International Energy Outlook.

Tbl 10 Primary Energy Growth
1965	2019	2050e
49 PWh	185 PWh	260 PWh

The 1965 estimate is inferred from Our World in Data and the EIA 2019 number.

Tbl 10: Primary Energy Use By Region
	2022	2050e	Δ
OECD	71	82	+11 PWh
USA	28	32	+3 PWh
EU	24	28	+4 PWh
Non-OECD	116	177	+62 PWh
China	48	58	+10 PWh
India	12	35	+23 PWh
Other Asia	14	25	+11 PWh
Africa	7	13	+6 PWh
World	187	260	+73 PWh

Over the next 30 years, the world is expected to increase its energy consumption by about 40%.

Fig 11: Energy Sources (2019)
Biomass	11 PWh	7%
Coal	44 PWh	28%
Oil	54 PWh	34%
Natgas	39 PWh	25%
Nuclear	7 PWh	4%
Hydro	10 PWh	6%
Wind	4 PWh	3%
Solar	2 PWh	1%
Total	173 PWh	100%

Non-fossil fuels are grossed up as if they had similar efficiency losses as fossil-fuels.

03: Emissions

Fig 1: CO2 Equiv, By Greenhouse Gas
CO2	38 GtCO2	86%
Methane	9 GtCO2e	20%
NOx,CFC,+	5 GtCO2e	11%
Land Charge	4 GtCO2e	9%
Total	55 GtCO2e	100%

Fig 3: By Emitting Use
Energy	37 GtCO2e	73%
Agriculture	10 GtCO2e	20%*
Other	4 GtCO2e	8%

If the land charge accrues to agriculture, then agriculture’s share increases from 20% to 2S%.

§3.2: Annual Atmosphere Change

Human Emissions: +38 GtCO2.
First-Year Natural Atmospheric CO2 Removal: ≈20 GtCO2.
(Total removal: 100s-1000s of years.)
Extra Human-Caused Atmospheric: +18 GtCO₂/year = +2.5 ppm/year.
1870: 2,200 GtCO₂ = 280ppm.
2021: 3,200 GtCO₂ = 420ppm.

Tbl 14: CO2 Emissions, 2022 and 2050e
	2022	2050e	Δ
OECD	12.1	12.1	-0.0 GtCO2
USA	4.8	4.8	-0.0 GtCO2
EU	3.8	3.7	-0.1 GtCO2
Non-OECD	24.2	30.8	+6.6 GtCO2
China	11.0	10.5	-0.5 GtCO2
India	2.7	5.8	+3.1 GtCO2
Other Asia	2.8	4.9	+2.0 GtCO2
Africa	1.3	2.0	+0.7 GtCO2
World	36.8	42.8	+6.6 GtCO2

The table in the text quotes log-growths. The table here shows GtCO2 instead.

Tbl17: CO2 Emissions (ca 2022)
	Total	pPpY
OECD	12.1 GtCO2	8.8 tCO2
USA	4.8 GtCO2	14.4 tCO2
Europe	3.8 GtCO2	6.4 tCO2
Not OECD	24.2 GtCO2	3.7 tCO2
China	11.0 GtCO2	7.6 tCO2
India	2.7 GtCO2	1.9 tCO2
Other Asia	2.8 GtCO2	2.4 tCO2
Africa	1.3 GtCO2	1.0 tCO2
Sub-Sahara	0.4 GtCO2	0.6 tCO2
World	36.3 GtCO2	4.6 tCO2

Fossil-fuel based CO2 emissions from pPpY = per Person per Year.

04 - 05 Temperature

§4.4.4. Atmosphere State

Long-Run: 2 × CO2 (ppm) => +1.0 C. Includes water vapor.
⇒ 50% increase from 280-420 ppm (+50%): ≈ 0.5 ° C

Data Basis: mostly IPCC 2021 6th Report for RCP 4.5 and 7.0. RCP 6.0 is now interpolated. Sometimes IPCC 5th.

Fig 5-9: Estimated Planetary Conditions
Year	CO2	Temp	SeaLvl
	in ppm	in dC	in m
Vostok
–100,000	236	–2.1
–30,000	206	–6.8	–80
–20,000	200	–8.1	–133
–10,000	240	–2.5	–62
0	280	–0.4	–0.1
Mann
1400	280	–0.3	0.0
1700	276	–0.8	0.0
1800	281	–0.5	0.0
NASA
1980	339	0.0	0.0
2000	370	+0.3	+0.2
2020	415	+1.0	+0.2
NASA and IPCC 2021 Report, Page SPM-29
RCP 4.5
2050e	500	+1.5	+0.3
2100e	560	+2.5	+0.3
RCP 6.0
2050e	500	+1.6	+0.3
2100e	720	+3.0	+0.4
RCP 7.0
2050e	600(?)	+1.7	+0.3
2100e	850(?)	+3.6	+0.5
Clark
10,000e	630	+3.0	+37

The base year is 1980. Clark et al’s estimate is based on RCP 6.0 extrapolated.

Fig 5.1: RCP Emissions
	2050e	2100e
RCP 4.5	45 GtCO2	15 GtCO2
RCP 6.0	55 GtCO2	50 GtCO2
RCP 7.0	60 GtCO2	80 GtCO2

Equivalent 2020 emissions: 39 GtCO2. RCP 6.0 was interpolated from RCP 4.5 and RCP 7.0.

§5.2: Expected Economic Damages

Terrestrial effects are difficult to assess: hotter but better.
More energetic weather phenomena.
Sea level effects: 400 million displaced, primarily in Bangladesh and Indonesia.

Relating Emissions in GtCO2 to PPM.

§5.6: Dangers

Speed of increase.
Dormant feedback loops.
Tipping points.
(Very rare asteroids, supervolcanos)

06 Economics

§6.3 Social Cost of CO2

Also optimal tax on CO2:
- more ⇒ curtail too much.
- less ⇒ pollute too much.
Sequestration cost is one ceiling.
Problems: judging harm, inefficient administration, corrupt administration, differential harm, escape.

See §6.2.: GDP by Region (2020)
Total (t$)	pPpY	Ppltn
OECD	$52.3	62%	$38,000	1.4b
USA	$20.9	25%	$63,000	0.3b
Europe	$15.3	18%	$34,200	0.4b
China	$14.7	17%	$10,400	1.4b
India	$2.7	3%	$1,900	1.4b
World	$84.7	100%	$10,900	7.8b

Estimates can vary. The IMF estimate of world GDP for 2021 is $94 trillion. The population estimate for 2021 is 7.9b (8.0b for 2022).

See GDP Forecasts, PwC
	In US$	in PPP
	2020	2020	2050e
OECD	62%
USA	25%	16%	12%
Europe	18%	15%	9%
China	17%	18%	20%
India	3%	7%	15%
World	100%	100%	100%

§6.5.5.: Marginal Thinking and Cost/Benefit

COP are not about eliminating global warming but about reducing it by “10–20%.”
- Consider RCP 6 to RCP 4.
- Reduction of global warming by 2050 by 5% (from about 1.7°C to about 1.6°C).
- Reduction of global warming by 2100 by 20% (from about 3°C to about 2.6°C).
Est. required reduction: ≈ 15 GtCO2/year.
4–5 GtCO2 for each 0.1°C reduction by 2100.
All US CO2 emissions: 4.7 GtCO2.
15 GtCO2 at $50/tCO2 about $750 billion:
- About 1% of World GDP. About $100 per person per year.
- About 1.5% of OECD GDP. About $500 per OECD inhabitant.
- About 3.5% of US GDP. About $2,000 per US resident.
- About size of US military spending.
- About size of US Public School education spending.
$50 cost is reducible through (a) smart ramping up of CO2 tax; (b) delay (tech).

(Warning: All above numbers are immensely huge.)

§6.3: Cost Concepts

Diminishing Returns;
Sunk Costs;
Learning Curves (FOAK);
Returns to Scale;
Optimal Delay.

07: IAMS

See Tbl 5: $50/tCO2 Tax
Product	Cost Change
Oil	Gasoline	+50%
Coal	+400%
Natgas	+100%
Tree	-$3/tree

See Fig 2-3: Important Scenarios
	Year	Base	Prefers	“2°C”	4.5	7.0
		Nordhaus			RCP
CO2 Tax	2020	$0	$45	$60
	2050e	$0	$110	$150
	2100e	$0	$300	$500
Welfare	2020	0	–0.15%	–0.14%
	2050e	0	–0.23%	–0.53%
	2100e	0	+0.42%	–0.71%
Emissions	2020	39Gt	33Gt	32Gt	39Gt	39Gt
(CO2)	2050e	60Gt	40Gt	34Gt	45Gt	60Gt
	2100e	71Gt	16Gt	–10Gt	10Gt	80Gt
Temp	pre-ind	≈–0.45°C
	1980	0.0°C
	2020	1.0°C
	2050e	2.1°C	2.0°C	2.0°C	1.5°C	1.7°C
	2100e	4.1°C	3.5°C	3.3°C	2.5°C	3.6°C

§7.4: Key IAMS Issues

sensitivity to discount rate.
estimating future parameters.
uncertainty and risk.
omitted choices: population, income inequality, other charities.

08: The Wrong Question

Irrelevant

Problem is understanding choices by decision-makers.
World outcome is not solution to world problem.
Problem is too big for OECD countries. Non-OECD countries are too poor to fight it.

09: Fantasy

Key Problems

§9.2:: Global SCC tax impossible without global government.
§9.3: Treaties not in self-interest. Excludability and free-riding incentives. No similar treaty ever effective.
§6: Carbon footprints known for decades. (Carbon-shaming or setting an example?)
Need to convince 8–11 billion people, not just OECD 10–15% thereof.

10: Reality

Best Viable Choices

§10.1: Adaptation.
§10.2: Local fossil-fuel taxes (PM Health costs: $10/tCO2 to $100/tCO2).
§10.3: Clean Technology.
§10.4: Reforestation w/ Lumber Harvesting.

10: Fossil Fuels Vs.

§11.2: Fossil Fuels

Achilles Heel: High mining and transport costs;
75% of fossil-fuel primary energy ends up as waste heat.
Primary energy vs. Nameplate Power.
PM Health costs: $10/tCO2 to $100/tCO2.

Fossil Fuel Alternatives

§11.3: Hydrogen: similar but far too expensive for many decades.
§11.4: Nuclear Power: • 1 Meltdown / 3,704 reactor years; • 500 (old) nuclear power plants worldwide; • waste disposal; • safer (pebble-bed) reactors?
§11.5: (Li) Batteries • <1/10 energy density of fossil fuels; • High power, Low capacity; • Almost perfectly in/out-efficient; • Tiny capacity on grid (≈ 10 min total).

§11.7: Propaganda Clarifications

Most clean-tech in lab will fail (true), but there are dozens of exciting techs in lab.
All numbers are immensely large — think 1/10 of all agriculture.
Space and materials needed for clean tech, but plenty are available long-run.
Clean-tech enjoys subsidies, but small compared to fossil fuels.

11: Electricity

§3: Fundamentals.

High-quality energy. Jack of all trades. High conversion efficiency to kinetic energy.
Typical daily demand pattern: Low at noon; Peaks at 7am and 8pm.

See Tbl 5: LCOE per MWh
	2020	2050e
Solar	$35	$15
Wind	$35	$20
Nuclear	$70	$60
Natgas, 24/7	$40	$45
Natgas, Peaker	$200	$200
Coal	$75	$65
Hydro	$55

Costs are in 2020-$ and representative utility-scale but vary by location.

See Tbl 6: Coal Plant Status 2022, in GW
	Oprtg	Cnstrct	Prmt	Anncd
OECD	501.0	16.0	5.0	3.9
USA	232.8	-	-	-
Europe	117.8	12.2	-	-
China	1,046.9	96.7	43.0	72.1
India	233.1	34.4	11.7	11.7
All others	≈280	≈37	≈20	≈24
World	2,067.7	184.5	78.9	111.8

Tbl 8: Storage Cost, 2030e
	Cost per MWh
Batteries	$120 or $200-$250
Natgas Peaker	$100-$200
Pumped Hydro	$130
Compressed Air	$100

See Fig 9: Needed E-Storage on Grid
% Clean Elec	Needed Hours
50%	1 hour
80%	10 hours
90%	100 hours
100%	1,000 hours
Currently	minutes

Tbl 11: E-Generation in TWh
Region	Year	USA	China	World
Coal	2020	774	4,313	8,244
	2050e	593	3,556	8,115
NatGas	2020	1,636	267	6,458
	2050e	1,953	803	7,306
Nuclear	2020	785	331	2,630
	2050e	594	1,002	3,025
Hydro	2020	283	1,117	4,034
	2050e	294	1,448	5,548
Wind	2020	343	574	1,741
	2050e	790	1,001	6,833
Solar	2020	132	281	832
	2050e	1,072	3,379	10,152
Total	2020	4,061	6,893	24,991
	2050e	5,458	11,230	41,953

These are secondary energy estimates, EIA base scenario.

§12.7: Transmission

About $2 million per GW per mile.
Cheap now only because generation is near use. Will become more expensive.
Giant regulatory mess.

13 Beyond Electricity

Fig 3: Vehicle Use Efficiency
	Fuel	Mvng	Total
Battery	95%	75%	70%
Hydrogen Fuel Cell	50%	40%	20%
Hydrogen Combustion	45%	30%	13%

13: Remediation

Key Points

§14.1: Removal cost is upper limit to Social Cost of Carbon Dioxide.
§14.2: Reforestation with lumber harvesting is cheapest method, perhaps as low as $10/tCO2 for first GtCO2.
Industrial CO2 removal projects seem hopelessly expensive for decades to come.
§14.3: Solar radiation management is worth investigating, but not (yet) deploying. Danger of unintended consequences.

15: Transition

Favorites

Increase innovation.
Share technology better.
Tax fossil fuels for local health.
Forestation.
Price by supply cost (time).
Uproot bad habits / nudges.
Reverse tech lock-in.
Coordinate transition.
Reduce green red tape.
Targeted Federal land leases.
Kill worst emitters.
Minor international agreements.