Carbon Pricing: Distribution & International

Revenue recycling and effectiveness

Recycling can preserve or destroy the steering effect

What: Carbon pricing works by changing relative prices of clean vs. dirty goods (the steering effect). How you recycle revenue affects whether that signal survives.

Why: Lump-sum ("climate dividend") rebates keep the steering effect intact. But subsidising dirty consumption/production again — fuel-price caps, car-commuter exemptions (Germany's 2022 ~17-cent-at-the-pump cut during the oil shock) — waters it down.

Remember: Even neutral lump-sum recycling can slightly dilute reductions because poorer households often have a larger budget share on polluting goods → the equity-pollution dilemma. Empirically minor (Simon Feind, PIK) because the curve mapping relative environmental impact to income is fairly flat.

The four pieces of information you need

To recycle efficiently and fairly, you must know all four:

1. Consumption-side ("use-side") costs — the extra cost at the pump and, under broad carbon pricing, costs traced through all products (hard to trace).
2. Source-side / production costs — the share firms can't pass through hits capital (top 2–3 deciles) and labour. Pass-through ≈ near-100% in energy/fuel, less in trade-exposed industry. Distribution of these is heterogeneous and under-studied.
3. Distribution of benefits — avoided climate damages + local co-benefits (clean air), which are typically pro-poor (poorer households live closer to pollution). Often ignored in revenue debates.
4. Efficiency of revenue recycling — transaction costs, and whether recycling waters down emission reductions (giving money back to emission-intensive users).

Distributional channels — consumption side evidence

Finland (Ahonen & Palanne 2025)

Remember: With clean micro-data on transport fuel: over the whole economy the burden is roughly proportional (flat) in % of income. But among households who own a car, it is clearly regressive. Households outside city centres, with children, and employed people face higher burdens. Crucially, income deciles explain only ~1.5% of variation in fuel-tax burdens → most variation is horizontal (within-decile).

Germany (German Council of Economic Experts micro-simulation)

Remember: Carbon pricing is slightly regressive in € and % of income. But add a per-capita lump-sum transfer → distributional profile flips: lower deciles gain on net, richer deciles bear a slightly larger burden.

US (Cronin & co. / gasoline)

Remember: Gasoline as % of total expenditure shows huge horizontal spread within deciles — from near-zero up to ~15%. (In some developing countries the pattern reverses and is concentrated in small upper deciles — you need income to own a car at all; the poorest just use public transport.)

Vertical vs. horizontal inequality

What: Vertical = across income deciles. Horizontal = within a decile (lifestyle: car ownership, rural residence, family structure).

Remember: Horizontal heterogeneity dominates fuel-tax burdens (Finland: deciles explain only ~1.5%). With a per-capita rebate, lower deciles can gain on net.

Distribution of benefits (German eco-tax case)

Remember: Using the 400-county (NUTS-3) data, the health co-benefits per capita are pro-poor — lower-income counties benefit more. Same pattern from low-emission zones. Avoided climate damages are also very likely pro-poor — but mostly accruing to the very poor abroad, not within your own country.

How to recycle the revenue

US economists' carbon-dividend statement

Remember: A prominent petition (incl. 28 Nobel laureates, under Biden) urged: all revenue returned via equal lump-sum rebates; the majority of families, including the most vulnerable, would gain more than they pay in higher energy prices. (Matches the German micro-simulation.)

Nesje et al. (2025) — global expert survey (N ≈ 442)

Remember (single most-preferred): Transfers to particularly affected households (~24%) top, then equal lump-sum (~15%), reductions in distortionary taxes (~15%), green R&D (~11%). So the US "equal lump-sum" prescription is only the second choice and only ~25% of experts would spend any revenue on it.

Remember (multiple options): Green R&D ~59%, affected households ~56%, distortionary taxes ~43%, lump-sum ~25%. Experts prefer a portfolio / mix, not one rule. Big cross-country heterogeneity: Africa/South America & France >50% to affected households; Norway favours cutting distortionary taxes + green R&D + renewables; Switzerland favours lump-sum + distortionary-tax cuts. Caveat: a broad mix means each channel's effect is small and non-salient to voters.

Double dividend

Remember: Recycling into cuts of distortionary taxes can produce a double dividend (cleaner environment and less tax distortion).

Country cases

Switzerland — the canonical example

Remember: ~CHF 120/tCO$_2$ levy (not on transport fuels). Recycling: 1/3 into a building program (energetic retrofits) + technology fund (green subsidy/R&D). 2/3 rebated — households get an equal per-capita lump sum via health insurance (Krankenversicherer), ~CHF 5 visible when comparing insurers (very efficient, low transaction cost, but not salient — only a minority of students noticed it); firms get it back proportional to their wage bill (Lohnsumme) (targets the labour-cost side, not capital). Contrast Canada, which mails cheques — very salient, but high transaction cost.

Austrian Klimabonus

Remember: €145 base (auto-paid to main-residence holders) + a regional adder for poorer public-transport access: +€0 (urban, good transit), +€50, +€100, +€145 (rural, basic transit) → up to double in rural areas. Income-differentiated: the bonus is taxable above ~€66,612 income → lower effective share for high earners. Plus a family bonus, reductions in distortionary salary/income taxes, and green subsidies → a strong recycling mix.

Section summary

Remember: Carbon/fuel pricing is not generally unfair — it depends on how the distribution channels combine, then it's a policy choice how to recycle. A mix is likely best for effectiveness + fairness, but a mix can get so complex that voters don't even notice they're being rebated (Swiss case).

International: free-riding and cooperation

Climate stability is a global public good

What: Non-excludable and non-rivalrous → every country prefers others to mitigate (free-riding) + economic competition among countries → global under-investment in mitigation.

Remember: ~30 years of game theory: equilibria are either large coalitions with little abatement or small coalitions with much abatement — both bad. We see global agreements, sub-global clubs, unilateral policies (sometimes with carbon-border adjustment), and international climate finance (especially adaptation aid to poor countries, often inside development aid).

Heterogeneous responsibility and damages

Historic responsibility (Our World in Data)

Remember: Cumulative CO$_2$ emissions to 2020 are very unequal — big contributions from Russia, the US, and (in recent decades) China in absolute terms; very little from Africa, relatively little from South America.

Geography of climate damages (Kotz/Bilal et al., Nature)

Remember: Damages hit poorer countries hardest. Africa, Latin America, large parts of Southern Asia lose most — up to ~−70% GDP per capita in the worst emission scenario. Europe could benefit; North America uncertain (expected slightly negative). This underpins why equity-weighting raises the SCC — link to Chapter 9.

Two mechanisms behind heterogeneous damages

Remember:

1. Differential marginal damage from baseline exposure — an extra degree hurts more where it's already hot (near the equator). Pure geography/meteorology.
2. Differential vulnerability / adaptive capacity — income-dependent. Netherlands dikes vs. Bangladesh sandbags against sea-level rise: richer countries adapt better for a given shock.

Burden-sharing rules

The canonical four

Remember:

1. Egalitarian / per-capita: all humans have equal rights to the atmosphere → distribute permits equally per capita (a global ETS).
2. Sovereignty / grandfathering: current emissions are a status quo → equal-% cuts; permits ∝ current emissions.
3. Polluter-pays: ∝ historical responsibility; equalises the ratio of abatement cost to emissions.
4. Ability-to-pay: ∝ capacity (GDP); equalises the ratio of abatement cost to GDP.

Extra rules beyond the four

Remember:

• Procedural / consensus — just follow the negotiation process to whatever political solution emerges (the current mode).
• Market-based — permits to the highest bidder (similar to sovereignty, auction-based).
• Equal-net-welfare-change — equalise net welfare changes across nations/individuals (need not equal per-capita permits).
• Maximin — improve the welfare of the worst-off nation/individual.
• Supply-side treaties — buy up and retire coal/oil → large transfers to fossil-owning countries.

Lange's survey finding

Remember: Andreas Lange surveyed people and policy negotiators (at the COPs): agreements should likely rest on polluter-pays + egalitarian — but support for each rule by region is explained by the economic-cost ranking → people endorse rules self-servingly (favour whichever is cheapest for their own region).

What's actually used

Remember: Today's consensus-building phase heavily emphasises sovereignty, with elements of ability-to-pay (adaptation finance; Kyoto's Annex A/B split). Egalitarian/polluter-pays are discussed but hard to implement in a consensus scheme.

History and Barrett's multi-track system

Treaty history

Remember: Earth Summit 1992 → created UNEP and UNFCCC. → Kyoto Protocol 1997: binding commitments for developed countries — but failed (some left, e.g. the US; others didn't meet targets). → Paris Agreement 2015: commitments made voluntary, but all countries (incl. previously exempt) now responsible.

Maamoun et al. — did agreements work?

Remember: Generalised synthetic control method — build counterfactual emission paths for Annex-I (binding-commitment) countries from non-Annex weights. Finding: emissions did drop in Annex-I relative to counterfactual — but largely driven by the EU. Identification worries: self-selection (signers were already willing), confounding with other policies, EU-specific ambition.

Barrett's multi-track climate-treaty system

Remember: Scott Barrett proposes multiple negotiation tracks instead of one mega-deal: (1) green R&D (shared funding + project selection), (2) mitigation + technology diffusion, (3) adaptation assistance, (4) geoengineering (build capacity as a last-resort response).

Nordhaus's two "lists of four" — don't conflate

Nordhaus's 4 steps for climate action (from his Nobel lecture)

Remember:

1. Information / education / awareness — people must accept the gravity of global warming.
2. Raise the price of CO$_2$ in some form.
3. Make it global, not local — this is where the Climate Club comes in.
4. Green R&D / rapid technological progress (geoengineering as the last refuge).

Nordhaus's 4 conditions for a successful Climate Club — see the next section. Easy to mix up.

The Climate Club (Nordhaus)

What it is

What: A voluntary group undertaking harmonised emission reductions with a focal international target carbon price (can be a tax, cap-and-trade, hybrid, or even subsidy scheme, as long as harmonised). Non-members face a uniform % tariff on their exports into the club region.

The 4 conditions for success

Remember:

1. A shared public-resource good that can be shared (here: global climate stability).
2. A cooperative arrangement with dues/membership fees set so members are still better off.
3. Non-members can be excluded or penalised at low cost to members (the crucial contentious point).
4. Stability — no member wants to leave (a self-enforcing agreement).

Quantitative results (15-region DICE)

Remember: A relatively low tariff (2–10%) can induce high participation at a target price of ~$50/tCO$_2$ (well below the SCC, but far above today's global average effective price). Reading the simulation graph: with no tariff, no country joins; even the lowest tariff brings everyone in at low target prices; raising the target price → fewer countries join. Net benefits are never negative across cases — largest in the EU and US (and China at high tariff rates) → some blocs have a self-interest to initiate a club.

Is the EU a Climate Club? CBAM

FOR / AGAINST

Remember: For: substantial carbon pricing via EU ETS, with prices well above the ~$50 threshold (esp. post-COVID spike); membership is voluntary (Brexit). The missing piece was penalising non-members — now addressed by the CBAM (Carbon Border Adjustment Mechanism).

Against: sub-global → only partial global benefits; narrow CBAM coverage; not a single unified price across all goods. Verdict: moving toward a Climate Club — the closest real-world approximation.

CBAM mechanics

Remember: Started January this year (transitional; full ~2026). Covers iron & steel, cement, fertiliser, aluminium, hydrogen, electricity — emission-intensive sectors. Applies only to large importers (>50 tCO$_2$-equivalent goods/year), who must report embedded carbon at the border, verified by accredited bodies, and surrender permits. If a carbon price was already paid in the production country, the difference is deducted (e.g. home price $20, EU ETS $80 → pay the $60 difference at the border). This incentivises other countries to introduce their own carbon prices (at least in export sectors) → pushes toward global carbon-price equalisation.

Key formulas & one-line takeaways

Key formulas

Polluter-pays: equalise $\dfrac{\text{abatement cost}}{\text{emissions}}$ across countries.

Ability-to-pay: equalise $\dfrac{\text{abatement cost}}{\text{GDP}}$ across countries.

CBAM payment: (EU ETS price − home carbon price) × embedded carbon.

Equity-weighting link: poorer regions suffer larger climate damages → equity weight $w_i=(c_i/\bar c)^{-\eta}$ raises the SCC (Chapter 9).

One-line takeaways

• Recycling shapes both fairness and effectiveness: lump-sum keeps the steering effect; subsidising dirty goods waters it down; the equity-pollution dilemma is empirically minor.
• Horizontal (within-decile) inequality dominates fuel-tax burdens — Finland: income deciles explain only ~1.5%.
• Benefits (clean-air co-benefits + avoided damages) are pro-poor and often ignored in revenue debates.
• Experts (Nesje et al. 2025) want a portfolio, not the US "equal lump-sum" rule; affected-household transfers top the single-choice ranking, green R&D tops the multi-select.
• Switzerland: 1/3 buildings, 2/3 rebated (households via health insurance, firms via wage bill); Austria: €145 + regional adder + income-taxable Klimabonus.
• Climate stability is a global public good → free-riding → either big-weak or small-strong coalitions.
• Damages geography (Kotz/Bilal et al.): Africa/Latin America/S. Asia up to −70% GDP/cap; Europe may benefit — via baseline exposure and adaptive capacity.
• Four burden-sharing rules (egalitarian, sovereignty, polluter-pays, ability-to-pay) + extras (procedural, market, equal-welfare, maximin, supply-side); Lange: applied self-servingly.
• Don't conflate Nordhaus's 4 steps for action with his 4 Club conditions; add Barrett's 4-track system.
• Nordhaus Club: ~$50 target price + 2–10% tariff → broad participation; no tariff → nobody joins.
• The EU is the closest real Climate Club; CBAM (iron/steel, cement, fertiliser, aluminium, hydrogen, electricity) supplies the missing penalty and pushes global price equalisation.