جبران پولی در سیاست آب و هوایی از منظر یک ارزیابی تعادل عمومی: مورد کشورهای صادرکننده نفت

This paper investigates the compensations that major oil producers have claimed for since the Kyoto Protocol in order to alleviate the adverse impacts of climate policy on their economies. The amount of these adverse impacts is assessed through a general equilibrium model which endogenizes both the reduction of oil exportation revenues under international climate policy and the macroeconomic effect of carbon pricing on Middle-East's economy. We show that compensating the drop of exportation revenues does not offset GDP and welfare losses because of the time profile of the general equilibrium effects. When considering instead compensation based on GDP losses, the effectiveness of monetary transfers proves to be drastically limited by general equilibrium effects in opened economies. The main channels of this efficiency gap are investigated and its magnitude proves to be conditional upon strategic and policy choices of the Middle-East. This leads us to suggest that other means than direct monetary compensating transfers should be discussed to engage the Middle-East in climate policies.

The compensation of developing countries for the adverse impacts of climate change and climate policies is one of the constant stumbling blocks of international climate negotiations. These adverse impacts encompass three distinct issues: climate change damages, higher energy prices affecting households' purchase power and firms' production costs and the reduction of exportation revenues in fossil fuel producing economies. Historically, it is under pressure of Middle-East countries and the Organization of the Petroleum-Exporting Countries (OPEC) that these concerns have been officially acknowledged at different stages of international negotiations, since article 4.8 of the UNFCCC1 and article 3.14 of the Kyoto protocol2 (Barnett and Dessai, 2002) until, more recently, Article 1 of the 2009 Copenhagen Agreement.3 This repetition is the sign that no tangible progress could be made about this sticking point of climate negotiations in the past decades. This impasse has obvious political roots, i.e. the reluctance of developed countries to grant large transfers towards countries perceived as rent seekers, especially in a context of public budget constraint. But, beyond this political dimension, compensations based on monetary transfers raise questions about both their amount and their efficiency for sustaining economic activity in a general equilibrium vision. This paper tries and frames these two sides of the compensation problem. The first question relates to the evaluation of climate policy losses in oil-exporting countries, which defines the compensations but remains a controversial topic in the literature. General equilibrium energy-economy models predict significant costs4 whereas dynamic partial equilibrium models find moderate losses.5 These opposite conclusions are related to the assumptions underlying the two approaches. The former conventionally assumes optimized trajectories under perfect foresight and flexible technical and market adjustments, which comes down to overlooking the potential co-benefits of climate policies permitted by the correction of baseline sub-optimalities. The latter do not consider the feedback effects of the oil sector on macroeconomic indicators and hence do not account for the reduction of world oil demand under climate policy, a potentially major adverse impact on oil-exporting economies. One ambition of this paper is thus to provide a comprehensive assessment of the cost of climate policy in oil-exporting countries through a combination of these two approaches, i.e. in a hybrid top-down/bottom-up framework (Hourcade et al., 2006). The second question relates to the effect of monetary transfers on economic activity and welfare in the recipient country, which has been investigated in a large body of literature on the empirics of “development aid and growth”. A recent survey by (Doucouliagos and Paldam, 2011) shows however that no univocal message can be derived from existing assessments. Some support the idea that development aid promotes growth,6 whereas others find it growth-neutral7 or even contributing to depress activity through indirect mechanisms undermining aid effectiveness (Rajan and Subramanian, 2005). Among these, (Rajan and Subramanian, 2011) typically demonstrate the role of real exchange rate overvaluation when trade effects and structural lock-ins are accounted for. This mechanism is a source of the ‘natural resource curse’ through its negative effect on local competitiveness and socio-economic development (e.g., Sachs and Warner, 2001, Frankel, 2010 and Ross, 2012). It is a particularly important dimension for the evaluation of monetary compensations in Middle-East countries and it calls for endogenizing terms-of-trade adjustments. We try and respond these two methodological challenges through a hybrid Computable General Equilibrium (CGE) energy-economy model that captures the limited flexibility of technical and economic adjustments under imperfect foresight, describes the domestic effects of adjustments on the terms-of-trade and endogenizes long-run structural change in response to price signals and geopolitical strategies (Section 1). This model is used to estimate the socio-economic consequences of an international climate policy on oil markets and its adverse impacts on Middle-East countries in terms of exportation revenues and macroeconomic activity (Section 2). This assessment serves as a basis for estimating the monetary transfers Middle-East countries may claim for in a climate policy context under two options depending whether they compensate losses of oil revenue or of economic activity (Section 3). An analytical study demonstrates that general equilibrium effects in a second-best setting create the risk of an efficiency gap, i.e. that the ex-post benefit of transfers is lower than predicted with an ex-ante calculation, and isolates its crucial determinants ( Section 4). Finally, numerical assessments confirm the relatively poor efficiency of monetary transfers to actually sustain economic activity in Middle-East economies ( Section 5). Section 6 concludes on the implications of this analysis for international negotiations and, in particular, on the trap of reducing the compensation problem in climate negotiations to a question of monetary transfers.

This paper discusses the question of compensation for the adverse impacts of a climate policy in a ‘thought’ experiment considering monetary transfers schemes and taking Middle-East countries as an example. This exercise helps pointing out mechanisms and orders of magnitude to identify the potentials and intrinsic limits of such approaches of compensation problems. Its major insight is about the impasses of a diplomatic language basing these compensations on observable indicators (here the oil exports) and ignoring the magnitude of the efficiency gap caused by general equilibrium effects. In a general equilibrium model representing the interactions between oil markets and the macroeconomy, we first show a time-lag between losses of oil exports and of macroeconomic activity measured in GDP. Oil export losses remain moderate in the short term, especially under a ‘low deployment strategy’ of oil production, while the GDP losses can be very high because Middle-East countries cannot quickly adjust to very high increase of their (currently very low) domestic energy prices. This mismatch explains why compensating transfers based on oil revenue losses cannot solve the transition problem. But, even fine-tuning compensations according to GDP losses proves to compensate only partly the economic slowdown due to a carbon constraint because of general equilibrium feedbacks which undermine the macroeconomic efficiency of monetary transfers. This ‘efficiency gap’ of transfers results in particular from the dependence of the domestic output to oil exportation revenues, the sensitivity of non energy sectors to price competition and the labor market rigidities which restrict the adaptive capacity of economies to changing conditions. In addition to this intrinsic limit to the effectiveness of transfers, our results show that the magnitude of the GDP losses to be compensated cannot rely on observable parameters since the magnitude of the efficiency gap of transfers is determined by the strategic choices of the Middle-East and also by the capacity of domestic policies to block Dutch disease mechanisms. These results show, beyond the specific case of oil exporters, the trap of reducing the compensation problem in climate negotiations to a question of monetary transfers. Other options are to be envisaged like technological transfers (Barrett, 2001 and Barrett, 2003) or innovative devices in climate finance (Hourcade et al., 2012) to ease the structural transition towards low carbon development paths and, in the case of Middle-East countries, towards the “beyond oil” era.