Permanence refers to GHG emission reductions that must be backed by guarantees in the event that they are reversed (e.g., re-emitted into the atmosphere). The Coalition on Agricultural Greenhouse Gases (C-AGG, 2010) developed a useful synopsis for managing risk of permanence. We have summarized and modified their work in table format below. Table B1 lays out the source of the risk and the ability of landowners and or policy makers to control this risk. For example, neither landowners nor policy makers have much control over natural disaster impact on GHG mitigation practices, but both have significant agency within socio-economic terms. Table B2, lays out mechanisms to help transparently address risks of reversal for GHG mitigation practices.
TABLE B1. Sources of risk to permanence of GHG mitigation practices
| Source of Risk* | Description | Landowner Control | Policy Control |
| Natural | Loss by disease, drought, flooding, insects, wildfire, wind, other natural disasters | low | low |
| Socio-Political | Loss by changing regulatory policy, political instability, or social unrest, or leakage | low | high |
| Technical | Loss if technologies or practices used fail to maintain carbon stocks or mitigate GHG as expected | low | low to high |
| Financial | Financial failure of an organization may lead to dissolution of agreements and change of management activities (a farm goes bankrupt and agreements are dissolved) | low to
high |
low to high |
| Socio-Economic | Higher-value alternative land uses, and rising opportunity costs can lead to a change of management activity or plans. | high | high |
* This table is adapted from C-AGG (2010) and attempts to illustrate the limitations of the technical potential described here-in.
Standards define the things that will be measured to gain market entry and how they will be measured. A highly measurable, verifiable, real, and permanent mitigation practice will have greater value and be easier to track. A practice that is less measurable, more difficult to verify, with potential reversibility will be more difficult and costly to track. The desire to maximize crediting farm practices must be weighed against the costs of implementation and the accounting burdens of verification. Likewise, upfront costs/crediting needs to be balanced with assessing risks into the future to ensure against future reversals for a specified period of time (sometimes called a permanence or a liability period).
Below in Table B2 is a list of mechanisms for addressing risk from an insufficient ability to measure, track and verify and/or accommodate conditions that may cause a reversal of mitigation.
TABLE B2. Managing risk to permanence of GHG mitigation practices
| Mechanism for Averting Risk* | Description | Consideration |
| Discounting | Discounting the potential mitigating potential by using a risk value to address the probability of carbon loss or reversal over a timeframe. | The disadvantage is certain projects may outperform but receive no credit, not rewarding innovative project managers. |
| Buffering | A portion of mitigation potential may be placed into a buffer reserve established over the term of the project and if no loss or reversal has occurred at the end of the term, the project manager is awarded the buffer. For example, if a project is quantified to address 100 Mg CO2e over 4 years, a portion (say 20 Mg CO2e) could be set aside, resulting in the landowner receiving payment of 20 Mg CO2e per year (instead of 25 Mg CO2e/yr). At the end of the 4th year, if all went as planned and the buffer was not needed to ensure project effectiveness, the landowner receives a final payment of 20 Mg CO2e. If, however, the project did not meet its mitigation potential, the buffer is not converted to a payment. | Assessing risk and assigning a required buffer value on a project-by-project basis may be time-consuming and burdensome for project owners and system administrators. |
| Pooling of similar practices | A program-wide pooled buffer account is maintained at all times by an administrator. All projects submit the same relative amount to the pool. All projects receive an average benefit at the end of the pooling period. Benefits and liabilities are thus shared among participants. | Regular monitoring and recalibration of buffer withholding percentages can be used to adjust the size of the pooled buffer account based on actual loss experience. |
| Pooling of diverse practices | A farm-scale or regional portfolio of different GHG mitigation opportunities is pooled (for discounting, buffering or self-insuring purposes), diversifying the risk of reversal by any one type of project in the portfolio. | As above. |
| Insurance | A farm or group of landowners may purchase private insurance to cover the risk of loss or reversal of GHG mitigation. | Assessing risk and underwriting the insurance mechanisms on a project-by-project basis could be costly and time-consuming. |
| Temporary Liability
|
Easements or project implementation agreements may legally require landowners to take actions that maintain carbon stocks or mitigation rates over a predefined time period. | A long-term easement may offer the best chance to maximize project crediting while ensuring that no intentional reversals occur. But few landowners may be willing to make long-term agreements. |
| Setting
Term Credits |
A commitment period (“term”) is defined for maintaining carbon stocks. At the end of the term, the project landowner must either renew the commitment for another term or the credits issued to the project must be replaced. | Responsibility for replacing the credits at the end of the term is generally assigned to the final buyer of the credits. Liability for any reversals that occur prior to the end of a term is generally assigned to the landowner. |
* Adapted from C-AGG (2010)
While Table B2 suggests a number of ways to reduce the risk of reversal by natural and human activities, an underlying concept to defining each of these issues is the timeframe of the accruing benefits and the timeframe of reversibility. For example, it can take 30 years to reach a new steady-state value of soil carbon after implementing a practice and that gain can be reversed in just a few years of tillage. Additionally, one should consider the timeframe of the GWP potency such as short-lived methane or long-lived nitrous oxide, relative to carbon sequestration. These things taken together inform prioritization of activities to advance Real, Measurable, Verifiable, and Permanent mitigation, anticipating intentional (socio-economic conditions) and unintentional (extreme weather) reversals.
Verification: Thinking about rigor for GHG accounting as well as other state goals
Verification is intended to help assure that practices are both Real and Permanent (see definitions above). Verification is defined as the “GHG emission reductions must result from projects whose performance can be readily and accurately quantified, monitored, and verified.”
The point of verification is accurate accounting from implemented activities. Verification upholds the integrity and quality of the data reported. Standardizing verification procedures promotes relevance, completeness, consistency, accuracy, and transparency of emissions reductions data reported by project developers. Transparent processes ensure projects are real, additional, permanent, verifiable and enforceable, compatible with other types of projects, support on-going monitoring, and minimize risk of invalid or double accounting. In this report, we apply the term Verifiable to practices that have robust and practical verification tools and methodologies. As mentioned above, one example is a manure storage unit cover and flare system equipped with a meter and temperature sensor that measures the gas flow and the flare effectiveness for documenting permanent destruction of methane. Another example is a forest management project with healthy growing trees that can be visually verified overtime for permanence or quantified by measuring tree diameter and height and using standard published allometric equations and factors to estimate stand volume and carbon content.
However, not all practices on farms have such a straightforward method for being ‘readily and accurately quantified, monitored and verified’. Farms are complex living systems and greenhouse gases move in all directions making accurate and complete assessment of all GHG difficult to accurately monitor. We ranked activities as “verifiable” if their verification methods were direct and likely cost-effective. The second highest ranking term we use is Reliable. Reliable practices reliably reduce GHG emissions but may either be calculated indirectly, or across a large number of steps in a supply chain requiring much work to quantitatively verify, or may be a small but certain practice that can be evaluated simply with a site visit (trees planted as a riparian buffer can be visually verified to be healthy and growing). The lowest ranking term for verification is Directionally Beneficial. Directionally Beneficial is applied to practices for which the benefit is too small or uncertain to merit the costs of formal verification, or verification is too onerous and therefore too costly, or a practice is easily reversible and potentially not a permanent practice (see also the discussion on Permanence in this Appendix). For example, no-till and reduced tillage have many benefits for soil health, with a small technical potential for increased soil carbon if performed continuously over the long term in careful combination with residue management, fertilizer management, and crop rotations, but it is not permanent and is very difficult to verify. However, as verification methods and tools develop in the future, the current ranking of practices in Table 3 could change.
A highly verifiable practice is a suitable candidate for state supported initiatives to support the GHG mitigation goals. A large and highly verifiable category offers a meaningful state-scale GHG mitigation opportunity. In contrast, a directionally beneficial practice is most likely best considered a GHG-mitigating co-benefit of some other state initiative. For example, no-till might best be considered a water quality initiative or soil health initiative with a possible small or impermanent co-benefit of GHG mitigation. Remember, verification is an accounting tool to support progress towards meeting a particular GHG mitigation goal. Verification costs money to implement and NYS should consider how it wants to prioritize spending. NYS may decide to support only highly verifiable and permanent GHG practices or direct money on implementing more directionally beneficial (not currently verifiable) practices that may also help meet other environmental goals such as clean air and clean water.
