My Climate Leadership and Community Protection Act Part 496 Comments

On July 18, 2019 New York Governor Andrew Cuomo signed the Climate Leadership and Community Protection Act (CLCPA), which establishes targets for decreasing greenhouse gas emissions, increasing renewable electricity production, and improving energy efficiency.  I have summarized the schedule, implementation components, and provide links to the legislation itself at CLCPA Summary Implementation Requirements.  On August 14, 2020 New York State Department of Environmental Conservation (DEC) Commissioner Basil Seggos released proposed part 496 regulations that defined the 1990 baseline emissions inventory for the CLCPA.   This post summarizes the comments I submitted on October 26, 2020.

I am following the implementation of the CLCPA closely because it affects my future as a New Yorker.  If they get it wrong it will be all the more difficult to get to the aggressive CLCPA targets.  The opinions expressed in this post do not reflect the position of any of my previous employers or any other company I have been associated with, these comments are mine alone.


This 1990 emissions inventory is important because many of the targets of the CLCPA are based on reductions from this baseline.  For example, there is a target to reduce GHG emissions to 60 percent of 1990 emissions levels by 2030.  The CLCPA includes specific requirements for the 1990 emission inventory that I am positive no legislator who voted for the law understood.

The law mandates an aggressive schedule for developing this inventory.  The CLCPA 1990 baseline is supposed to be set in 2020 but the first statewide greenhouse gas emissions report isn’t due until 2021.  The statewide emissions report is defined as a “comprehensive evaluation of the inventory best available science and methods of analysis, including the comparison and reconciliation of emission estimates from all sources, fuel consumption, field data, and peer-reviewed research”.  It “shall clearly explain the methodology and analysis used in the department’s determination of greenhouse gas emissions and shall include a detailed explanation of any changes in methodology or analysis, adjustments made to prior estimates, as needed, and any other information necessary to establish a scientifically credible account of change”.  The 1990 baseline for the statewide GHG emission limits has similar quality requirements: “In order to ensure the most accurate determination feasible, the department shall utilize the best available scientific, technological, and economic information on greenhouse gas emissions and consult with the council, stakeholders, and the public in order to ensure that all emissions are accurately reflected in its determination of 1990 emissions levels”.

I compared the proposed Part 496 1990 emission inventory with the previous “official” New York greenhouse gas emission inventory that was prepared by the New York State Energy Research and Development Authority (NYSERDA) in two earlier posts.  The Part 496 Regulatory Impact Statement (RIS) includes a section titled Key Requirements of the 1990 Emission Baseline section that explains the CLCPA mandates that required DEC to develop a new official inventory.   These requirements significantly affect the greenhouse gas (GHG) emission total for the State.  According to the latest edition of the NYSERDA GHG emission inventory (July 2019) Table S-2 New York State GHG Emissions 1990–2016 the New York State 1990 GHG emissions were 236.18 MMtCO2e The proposed Part 496 regulation 1990 emissions inventory total is 401.38 MMtCO2e for an increase of 165.2 MMtCO2e.

Summary of 1990 Emission Inventories
Regulatory Impact Statement Table 1 Inventory in GWP20.
Sector CO2 CH4 N2O PFCs HFCs SF6 Total
Energy 254.43 70.12 1.31 4.00 329.87
IPPU 1.67 0.00 0.00 0.90 0.02 0.01 2.60
AFOLU 0.05 13.07 4.01 17.13
Waste 3.03 48.25 0.50 51.78
Total 259.18 131.45 5.83 0.90 0.02 4.01 401.38
NYSERDA July 2019 Table S-2 Emission Inventory in GWP100
Sector CO2 CH4 N2O PFCs HFCs SF6 Total
Energy 208.96
IPPU 3.99
AFOLU 8.37
Waste 14.86
Total 236.18


In my first comment I addressed the contradiction in the emission inventory requirements in two sections of the CLCPA.  How can § 75-0107, Statewide greenhouse gas emissions limits, establish a limit estimated pursuant to § 75-0105 which is due later than this requirement?  Both sections mandate the use of the “best available” information and consultation with the public, but the timing requirements preclude that from happening.

As shown above there are significant differences in the Part 496 proposed inventory and the July 2019 NYSERDA inventory.  The July 2019 emission inventory relied primarily on Intergovernmental Panel on Climate Change (IPCC) methods but because of CLCPA mandates, GHG emissions that occur outside of the boundaries of New York State have to be included if they are associated with the use of energy within the State and the carbon equivalent emissions have to use a global warming potential time horizon of 20 years instead of 100 years.  One basic flaw in the Part 496 regulation’s supporting documentation is that in order to be complete the emission factor, activity factors or throughput and the reference for those choices made for each value listed in the inventory has to be provided.  That information is not available.

The RIS is the only documentation provided for the proposed Part 496 inventory and it only provides less than ten applicable references justifying the values chosen.  Given the significant departure from IPCC protocols, the documentation is inadequate.  Reading the RIS gives the impression that methane inventorying is without controversy.  However, as shown in the references I provided, Methane Reference Summary, this clearly is not the case. The overview paper  M. Saunois et al.2020: The Global Methane Budget 2000–2017 notes in the abstract: “The relative importance of CH4 compared to CO2 depends on its shorter atmospheric lifetime, stronger warming potential, and variations in atmospheric growth rate over the past decade, the causes of which are still debated. Two major challenges in reducing uncertainties in the atmospheric growth rate arise from the variety of geographically overlapping CH4 sources and from the destruction of CH4 by short-lived hydroxyl radicals (OH)”.  In order to justify the values used in the inventory these issues should be addressed in the documentation.

The major difference in this inventory compared to previous NYS inventories is due to changes in the methane inventory.  I believe that the changes in the inventory due to methane can be traced to Dr. Robert Howarth.  He not only helped draft the Climate Act but also now is a vocal member of the Climate Action Council.  While this accounts for his outsized impact on the inventory that does not necessarily mean that his views justify the changes.  In the Howarth 2020 paper he claims “Some evidence indicates that shale-gas development in North America may have contributed one-third of the total global increase in methane emissions from all sources over the past decade (Howarth 2019).”  This paper and other similar papers claim that “methane emissions can contribute significantly to the GHG footprint of natural gas, including shale gas”.  There is a problem however, because much other evidence contradicts those claims.

In my comments I provided references with other evidence that I think should be included in the documentation.  While it may be that the State will choose to ignore those results, there is a CLCPA mandate to provide a “detailed explanation of any changes in methodology or analysis, adjustments made to prior estimates, as needed, and any other information necessary to establish a scientifically credible account of change”.  Clearly the existing documentation fails to meet that standard.

Based on my experience I believe there is a huge hurdle for Howarth’s methane inventory.  Although I have been involved with emissions inventories for over 45 years, I do not have specific experience with natural gas production emissions.  However, over that time I learned early on that the gold standard check on any emissions inventory is comparison of the inventory estimate with observed ambient monitoring.  If there is a high quality, long-term monitoring network that measures the pollutant in the inventory and those measurements do not reflect the trend in the inventory then the inventory is wrong.  Lan et al., 2019 evaluated data from the National Oceanic and Atmospheric Administration Global Greenhouse Gas Reference Network and determined trends for 2006–2015.  This covers the period when Pennsylvania shale-gas production increased tremendously.  According to the plain language summary for the report:

“In the past decade, natural gas production in the United States has increased by ~46%. Methane emissions associated with oil and natural gas productions have raised concerns since methane is a potent greenhouse gas with the second largest influence on global warming. Recent studies show conflicting results regarding whether methane emissions from oil and gas operations have been increased in the United States. Based on long‐term and well‐calibrated measurements, we find that (i) there is no large increase of total methane emissions in the United States in the past decade; (ii) there is a modest increase in oil and gas methane emissions, but this increase is much lower than some previous studies suggest; and (iii) the assumption of a time‐constant relationship between methane and ethane emissions has resulted in major overestimation of an oil and gas emissions trend in some previous studies.”

As a result of the fact that the relevant high quality, long-term monitoring network does not show a trend consistent with the work of Howarth I believe that unequivocally supports Dr Lewan’s conclusion that his ideas, perspectives, and calculations on methane emissions from shale gas are invalid.  If the State cannot explain this inconsistency then their inventory is wrong.


In order to meet the “best available science and methods of analysis” criteria of the CLCPA, the DEC documentation should address the current methane debate by summarizing articles on both sides of methodology differences, explain how those differences affect the Part 496 1990 emission inventory relative to previous inventories, and then provide the rationale for picking one approach over the other.  Because this level of detail is not provided, I recommended that the Part 496 inventory should be re-proposed with that information.

There is a big issue lurking in these numbers.  Part 496 lists the baseline GHG emissions inventory for 1990 but the State has not provided their estimated inventory for a recent year.  The GHG inventory with the most recent data covers the period 1990 to 2016 and was published in July 2019.  That inventory is not consistent with the requirements of the CLCPA, but in that inventory New York’s CO2 emissions went from 236.2 MMtCO2e to 205.6 MMtCO2e a 13% decrease.  I would not be surprised that the revised inventory’s emphasis on methane will show that there is a much smaller decrease over that time frame.  That will make attaining the 2030 CLCPA 40% reduction from 1990 emissions level harder to meet.

Author: rogercaiazza

I am a meteorologist (BS and MS degrees), was certified as a consulting meteorologist and have worked in the air quality industry for over 40 years. I author two blogs. Environmental staff in any industry have to be pragmatic balancing risks and benefits and ( reflects that outlook. The second blog addresses the New York State Reforming the Energy Vision initiative ( Any of my comments on the web or posts on my blogs are my opinion only. In no way do they reflect the position of any of my past employers or any company I was associated with.

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