Phase 2: Inventory

Within one year, a city must assess the current impacts of climate change in his/her city. To do so, the city must 1) Build and complete a community-wide GHG invetory with a breakdown of emissions for buildings and transport sectors, using the GPC standard; (2) Identify climate hazards; and (3) Report on both via the CDP or carbonClimate Registry questionnaires.

(A) Mitigation Compliance Requirements

City-wide GHG emission inventories need to meet the reporting requirements set out in the Global Protocol for Community-scale GHG emissions (GPC). Cities are recommended to use the carbonn Climate Registry reporting platform which has all appropriate sections available in a simple to use worksheet.

The following data needs to be provided:

City information:

  • Inventory year (defined as a continuous 12-month period) however the inventory year may be no more than three years prior to the reporting year
  • Geographic boundary (spatial dimension or physical perimeter)
  • Land area (in km2)
  • Population current
  • City GDP (in $USD)

Emission data needs to be reported by sub-sector and scope, and in metric tonnes of CO2e (carbon dioxide equivalents) as set out in the carbonn climate registry worksheets (example of carbonn worksheets here). Within one year, cities must report emissions from stationary energy and in boundary travel in as many sectors as possible. Reporting by individual GHG is recommended in year one however the minimum acceptable form is CO2e in metric tonnes. Within year one the requirement is emissions data is from Stationary Energy (residential, industrial and commercial sectors) and in boundary transport. In year one Waste reporting  is optional, however a city’s emissions report on waste in year one can be for equivalent carbon dioxide (CO2) only.

The activity data underpinning the GHG inventory must be disclosed and reported within two years.

Within three years a BASIC inventory is required which covers Stationary Energy, Inbound Travel and Waste by scope 1 and 2. Within three years a city report must include reporting on three gases, carbon dioxide (CO2) methane (CH4) and nitrous oxide (N2O). The activity data underpinning the GHG inventory must be disclosed and reported with this inventory. Cities are, however, strongly encouraged to report emissions from all three sectors (Stationary Energy, Transportation and Waste) and all relevant subsectors if available as soon as they are able.

In general cities are strongly encouraged to report emissions of all three major GHGs (CO2, CH4, N2O) as soon as they are able to. Additional GHGs are optional: HFCs, PFCs, SFand NF3. Additional activities are optional: e.g. transboundary travel, industrial processes and product use (IPPU) and agriculture, forestry and land use (AFOLU).

Notation keys will be used to accommodate limitations in data availability and differences in emission sources between reporting cities. The notation Key “NE”, which means not estimated, will not be accepted for any mandatory emission sources. A data quality assessment (for activity data and emissions factors) should be conducted. Where incomplete data, a default value of “low” is applied. The carbonn worksheets will guide the user to fill in all compulsory fields including notation keys.

Supportive activity data

To arrive at the GPC inventory, calculations will need to be made using relevant emissions factors, coeffcients and formulae concerning the fossil fuels used or waste and other emissions. Detailing the sources of foundation reports and/or calculations for Stationary Energy, Transport, Waste and other sectors is required. At least three gases breakdown will be required.


(B) Adaptation compliance requirements

Covenant of Mayors compliance for adaptation requires that participating cities undertake a program of climate change risk and vulnerability assessment and adaptation planning within a three year period of joining the compact.

  1. Hazards reporting

Within the first year cities must report on both the current and future climate hazards that they face. The carbonn Climate Registry reporting platforms include questions that allow cities to nominate the current and future hazard they face using the terminology of the City Climate Hazard Taxonomy. This can be completed on the carbonn reporting worksheets.

  1. Vulnerability assessment

Cities must conduct a climate change risk and/or vulnerability assessment within two years of joining.

A climate change vulnerability assessment is a qualitative and/or quantitative assessment of the degree to which a system is susceptible to, or unable to cope with, adverse effects of climate change, including climate variability and extremes. Vulnerability is a function of the character, magnitude, and rate of climate variation to which a system is exposed, its sensitivity, and its adaptive capacity. Climate change risks are usually defined as the potential for consequences where something of human value (including humans themselves) is at stake and where the outcomes is uncertain. Climate change risk is often represented as the probability of occurrence of hazardous climate events, or trends multiplied by the consequence of these events occur. To be compliant a city climate change risk and/or vulnerability assessment must consider both current and future climate conditions.

Next phase