What types of ratcheting-up mechanisms exist and how could they be implemented in the context of a 2015 agreement? Could you provide examples from existing legal regimes and legal architectures?
Summary: Ratcheting-up provisions are included in the Montreal Protocol on Substances that Deplete the Ozone Layer and the Minamata Convention and, to some extent in the Kyoto Protocol. Some authors have indicated that the inclusion of a ratcheting up mechanism á la Montreal Protocol would require a shift from a ‘targets and timetable’ approach to a ‘phasing-out’ approach.
The term ‘ratcheting up’ is commonly deployed to refer to the fact that a legal instrument provides for periodical reviews enabling the adoption of increasingly stringent requirements upon its parties. The question concerns ‘ratcheting up’ in the specific context of the new agreement that UNFCCC parties are expected to adopt by 2015 and implement from 2020. The questions consists of two elements:
1) What types of ratcheting-up mechanisms exist and examples from existing legal regimes and legal architectures;
2) How ratcheting-up mechanisms could be implemented in the context of a 2015 agreement.
These two questions will be addressed in turn.
1) What types of ratcheting-up mechanisms exist and examples from existing legal regimes and legal architectures
Some international environmental instruments include provisions concerning the progressive ratcheting-up of commitments. The most famous example is the Montreal Protocol on Substances that Deplete the Ozone Layer to the Vienna Convention for the Protection of the Ozone Layer. In 2009 the Vienna Convention achieved universal ratification and all parties to the Vienna Convention have ratified the Protocol. The Montreal Protocol initially requested parties to freeze and then reduce their consumption of selected ozone depleting substances, with commitments that were differentiated for developed and developing country parties. Parties’ commitments were progressively ratcheted up by means of a series of adjustments and amendments, to eventually require the complete phase-out of most ozone depleting substances, in both developed and developing countries.
The Montreal Protocol addresses the issue of ratcheting-up by requesting that every four years parties assess the control measures of ozone depleting substances on the basis of ‘available scientific, environmental, technical and economic information,’ and with the help of a panel of experts. Based on these assessments, the Montreal Protocol lays down a procedure to carry out adjustments and reductions of production and consumption of the controlled substances listed in its Annexes. In cases where reaching consensus is not possible, adjustments can be adopted by a two-thirds majority vote of the parties present and voting. The adjustments are binding on all parties. Amendments of the Montreal Protocol, instead, have followed the procedure laid down in the Vienna Convention, and entered into force only for those parties that ratified them. The Montreal Protocol gives developing countries a ten-year period to delay compliance with control measures, with graduation criteria based on per capita consumption of ozone-depleting substances for determining when a country no longer qualifies for the ‘grace’ period. Finally, the phasing-out of ozone depleting substances was supported by the prohibition to import controlled substances from non-parties. Implementation of the Montreal Protocol is generally regarded as a success.
One recent instrument that followed the ‘ratcheting-up’ approach embedded in the Montreal Protocol is the Minamata Convention on Mercury, adopted in October 2013 and not yet into force. The convention is aimed to protect human health and the environment from anthropogenic emissions and releases of mercury and mercury compounds. To achieve this objective, the convention provides the progressive phasing-out of selected ‘mercury-added’ products and of the use of mercury in manufacturing processes listed in its annexes. The convention provides that parties periodically evaluate its effectiveness, ‘facilitated’ by consideration of ‘comparable monitoring data on the presence and movement of mercury and mercury compounds,’ as well as ‘trends in levels of mercury and mercury compounds in biotic media and vulnerable populations,’ and on the basis of ‘available scientific, environmental, technical, financial and economic information.’
The convention also provides for the periodical review of the annexes and lays out a procedure for their amendment. The reviews shall take into account: proposals submitted by parties; information collected and maintained by the Secretariat on the basis of parties’ submissions; and the availability of mercury-free alternatives that ‘are technically and economically feasible, taking into account the environmental and human health risks and benefits.’
When consensus cannot be reached, annexes can be adopted by a three-fourths majority vote of the parties present and voting at a meeting. Unlike the Montreal Protocol, the Minamata Convention provides the possibility to opt-out from additional annexes within a one-year time limit, after which amendments enter into force for all parties.  Finally, the convention includes restrictions on the trade of mercury, subject to some distinguos. Overall, the Minamata Convention has adopted a more cautious approach to reviews and amendments than that embedded in the Montreal Protocol. As the treaty is not yet in force, it is early to say whether the Minamata Convention will manage to replicate the success of the Montreal Protocol. The first, and so far only, state to have ratified the convention is the US.
The Kyoto Protocol may be regarded as a half-hearted attempt to replicate the ratcheting-up approach embedded in the Montreal Protocol. The periodical reviews under the Kyoto Protocol, in fact, merely require that parties ‘take appropriate action.’ The timescale of such reviews is left undetermined and, like the Minamata Convention, the Kyoto Protocol includes provisions enabling the opting-out from the adoption and/or amendments to the annexes.
In a nutshell, the elements missing in the Kyoto Protocol vis-à-vis the Montreal Protocol are:
1. Periodical reviews based on scientific evidence and the advice of a panel of experts, potentially resulting in adjustments to the treaty; 
2. Adjustments binding on all parties, even when adopted by majority voting;
3. Trade restrictions with non-parties.
2) How ratcheting-up mechanisms could be implemented in the context of a 2015 agreement.
The literature suggests that, to be replicated in the context of the climate regime, the ‘flexible’ adjustment procedure embedded in the Montreal Protocol to ratchet up parties’ commitments would need some adjustment.
One author underscores how, while the Kyoto Protocol includes limits on national greenhouse gas emissions, the Montreal Protocol limits the production and consumption (rather than emissions) of ozone-depleting substances. Along similar lines, another author suggests that, to successfully build upon the template drawn in the Montreal Protocol, a phasing-out approach should be adopted under the climate regime. This approach would entail treating greenhouse gases differently, depending on the technologies available to address their emissions; and adopting technical standards for their phasing out, coupled with adequate support, both financial and in terms of capacity building.
Importantly, this literature also draws attention to caveats to bear in mind when drawing parallels between the ozone and the climate regimes. The ozone regime is relatively small in scope, encompassing selected economic sectors and activities, whereas the climate regime is virtually all-encompassing. The difficulty of using trade bans in the context of the climate regime is equally underscored, pointing out how the debate on this specific issue has proven particularly divisive at climate negotiations.
 The Vienna Convention for the Protection of the Ozone Layer, 26 ILM 1529 (1985) (hereinafter, Vienna Convention): http://ozone.unep.org/new_site/en/vienna_Convention.php. The Montreal Protocol on Substances that Deplete the Ozone Layer, 26 ILM 1541 (1987) (hereinafter, Montreal Protocol).
 Montreal Protocol, Article 2 and Annex A.
 A full compilation of adjustment and amendments to the Montreal Protocol may be found in the Handbook on the Montreal Protocol (UNEP, 2012), pp. 641-695, available at: http://ozone.unep.org/new_site/en/Treaties/treaties_decisions-hb.php?sec_id=150. A brief summary of the adjustments and amendments to the Montreal Protocol may be accessed here: http://www.iisd.ca/vol19/enb19100e.html
 Montreal Protocol, Article 6: ‘Beginning in 1990, and at least every four years thereafter, the Parties shall assess the control measures provided for in Article 2 and Articles 2A to 2I on the basis of available scientific, environmental, technical and economic information. At least one year before each assessment, the Parties shall convene appropriate panels of experts qualified in the fields mentioned and determine the composition and terms of reference of any such panels. Within one year of being convened, the panels will report their conclusions, through the Secretariat, to the Parties.’ (Emphasis added)
 Montreal Protocol, Article 2, paragraph 9: ‘a) Based on the assessments made pursuant to Article 6, the Parties may decide whether: i) Adjustments to the ozone depleting potentials specified in Annex A, Annex B, Annex C and/or Annex E should be made and, if so, what the adjustments should be; and ii) Further adjustments and reductions of production or consumption of the controlled substances should be undertaken and, if so, what the scope, amount and timing of any such adjustments and reductions should be; b) Proposals for such adjustments shall be communicated to the Parties by the Secretariat at least six months before the meeting of the Parties at which they are proposed for adoption; c) In taking such decisions, the Parties shall make every effort to reach agreement by consensus. If all efforts at consensus have been exhausted, and no agreement reached, such decisions shall, as a last resort, be adopted by a two-thirds majority vote of the Parties present and voting representing a majority of the Parties operating under Paragraph 1 of Article 5 present and voting and a majority of the Parties not so operating present and voting; (d) The decisions, which shall be binding on all Parties, shall forthwith be communicated to the Parties by the Depositary. Unless otherwise provided in the decisions, they shall enter into force on the expiry of six months from the date of the circulation of the communication by the Depositary.’ (Emphasis added)
 Vienna Convention, Article 9, paragraph 4.
 Montreal Protocol, Article 5: ‘1. Any Party that is a developing country and whose annual calculated level of consumption of the controlled substances is less than 0.3 kilograms per capita on the date of the entry into force of the Protocol for it, or any time thereafter within ten years of the date of entry into force of the Protocol shall, in order to meet its basic domestic needs, be entitled to delay its compliance with the control measures set out in paragraphs 1 to 4 of Article 2 by ten years after that specified in those paragraphs. However, such Party shall not exceed an annual calculated level of consumption of 0.3 kilograms per capita. Any such Party shall be entitled to use either the average of its annual calculated level of consumption for the period of 1995 to 1997 inclusive or a calculated level of consumption of 0.3 kilograms per capita, whichever is the lower, as the basis for its compliance with the control measures. 2. The Parties undertake to facilitate access to environmentally safe alternative substances and technology for Parties that are developing countries and assist them to make expeditious use of such alternatives. 3. The Parties undertake to facilitate bilaterally or multilaterally the provision of subsidies, aid, credits, guarantees or insurance programmes to Parties that are developing countries for the use of alternative technology and for substitute products.’ (Emphasis added)
 Montreal Protocol, Article 4.
 Minamata Convention, Article 1.
 Minamata Convention, Articles 4-5 and Annexes A and B.
 Minamata Convention, Article 22: ‘1) The Conference of the Parties shall evaluate the effectiveness of this Convention, beginning no later than six years after the date of entry into force of the Convention and periodically thereafter at intervals to be decided by it. 2) To facilitate the evaluation, the Conference of the Parties shall, at its first meeting, initiate the establishment of arrangements for providing itself with comparable monitoring data on the presence and movement of mercury and mercury compounds in the environment as well as trends in levels of mercury and mercury compounds observed in biotic media and vulnerable populations. 3) The evaluation shall be conducted on the basis of available scientific, environmental, technical, financial and economic information, including: (a) Reports and other monitoring information provided to the Conference of the Parties pursuant to paragraph 2; (b) Reports submitted pursuant to Article 21; (c) Information and recommendations provided pursuant to Article 15; and (d) Reports and other relevant information on the operation of the financial assistance, technology transfer and capacity-building arrangements put in place under this Convention.’ (Emphasis added)
 Minamata Convention, Article 4: ‘8) No later than five years after the date of entry into force of the Convention, the Conference of the Parties shall review Annex A and may consider amendments to that Annex in accordance with Article 27. 9) In reviewing Annex A pursuant to paragraph 8, the Conference of the Parties shall take into account at least: (a) Any proposal submitted under paragraph 7; (b) The information made available pursuant to paragraph 4; and (c) The availability to the Parties of mercury-free alternatives that are technically and economically feasible, taking into account the environmental and human health risks and benefits.’ See also Minamata Convention, Article 5: ‘10) No later than five years after the date of entry into force of the Convention, the Conference of the Parties shall review Annex B and may consider amendments to that Annex in accordance with Article 27. 11) In any review of Annex B pursuant to paragraph 10, the Conference of the Parties shall take into account at least: (a) Any proposal submitted under paragraph 9; (b) The information made available under paragraph 4; and (c) The availability for the Parties of mercury-free alternatives which are technically and economically feasible taking into account the environmental and health risks and benefits.’ (Emphasis added)
 Minamata Convention, Article 27, paragraph 3: ‘The following procedure shall apply to the proposal, adoption and entry into force of additional annexes to this Convention: (a) Additional annexes shall be proposed and adopted according to the procedure laid down in paragraphs 1–3 of Article 26; (b) Any Party that is unable to accept an additional annex shall so notify the Depositary, in writing, within one year from the date of communication by the Depositary of the adoption of such annex. The Depositary shall without delay notify all Parties of any such notification received. A Party may at any time notify the Depositary, in writing, that it withdraws a previous notification of non-acceptance in respect of an additional annex, and the annex shall thereupon enter into force for that Party subject to subparagraph (c); and (c) On the expiry of one year from the date of the communication by the Depositary of the adoption of an additional annex, the annex shall enter into force for all Parties that have not submitted a notification of non-acceptance in accordance with the provisions of subparagraph (b).’ (Emphasis added)
 Minamata Convention, Article 3, paragraph 6: ‘Each Party shall not allow the export of mercury except: (a) To a Party that has provided the exporting Party with its written consent, and only for the purpose of: (i) A use allowed to the importing Party under this Convention; or (ii) Environmentally sound interim storage as set out in Article 10; or (b) To a non-Party that has provided the exporting Party with its written consent, including certification demonstrating that: (i) The non-Party has measures in place to ensure the protection of human health and the environment and to ensure its compliance with the provisions of Articles 10 and 11; and (ii) Such mercury will be used only for a use allowed to a Party under this Convention or for environmentally sound interim storage as set out in Article 10.’ (Emphasis added)
 Kyoto Protocol, Article 21: ‘4) The Parties shall make every effort to reach agreement on any proposed annex or amendment to an annex by consensus. If all efforts at consensus have been exhausted, and no agreement reached, the annex or amendment to an annex shall as a last resort be adopted by a three-fourths majority vote of the Parties present and voting at the meeting. The adopted annex or amendment to an annex shall be communicated by the secretariat to the Depositary, who shall circulate it to all Parties for their acceptance. 5) An annex, or amendment to an annex other than Annex A or B, that has been adopted in accordance with paragraphs 3 and 4 above shall enter into force for all Parties to this Protocol six months after the date of the communication by the Depositary to such Parties of the adoption of the annex or adoption of the amendment to the annex, except for those Parties that have notified the Depositary, in writing, within that period of their non-acceptance of the annex or amendment to the annex. The annex or amendment to an annex shall enter into force for Parties which withdraw their notification of non-acceptance on the ninetieth day after the date on which withdrawal of such notification has been received by the Depositary.’ (Emphasis added)
 Kyoto Protocol, Article 9: ‘1) The Conference of the Parties serving as the meeting of the Parties to this Protocol shall periodically review this Protocol in the light of the best available scientific information and assessments on climate change and its impacts, as well as relevant technical, social and economic information. Such reviews shall be coordinated with pertinent reviews under the Convention, in particular those required by Article 4, paragraph 2 (d), and Article 7, paragraph 2 (a), of the Convention. Based on these reviews, the Conference of the Parties serving as the meeting of the Parties to this Protocol shall take appropriate action. 2) The first review shall take place at the second session of the Conference of the Parties serving as the meeting of the Parties to this Protocol. Further reviews shall take place at regular intervals and in a timely manner.’ (Emphasis added)
 D. Bodansky, W[h]ither the Kyoto Protocol? Durban and Beyond, (Harvard Project on Climate Agreements, 2011), at 5.
 S. Barrett, ‘Climate Treaties and the Imperative of Enforcement’ 24 (2) Oxford Review of Economic Policy 239 (2008).
 D. Bodansky, ‘What’s in a Concept? Global Public Goods, International Law, and Legitimacy’ 23 (3) European Journal of International Law (2012), 651
 S. Barrett, Why Cooperate? The Incentive to Supply Global Public Goods (Oxford University Press, 2007), 77-101.