How Should Cities Measure Their Greenhouse Gas Emissions?
The World Resources Institute, C40 Cities and the ICLEI – Local Governments for Sustainability, have published their second version of the Global Protocol for Community-scale Greenhouse Gas Emissions (GPC) and are seeking feedback from city officials and climate experts in all related fields.
Measuring the climate impact of cities is of vital importance for the future of carbon accounting, enabling cities to have much greater awareness of and therefore control of their activities in order to counter global warming. What is measurable can be reduced. But a universally agreed standard is required that avoids double accounting yet includes all potential sources of emissions caused by human habitation within city boundaries.
Besides the above organisations, the World Bank, UNEP and UN -HABITAT have all collaborated on developing the standard so that cities of all sizes no matter where they are may be able to use it. This version follows the first edition, published just over two years ago, which has since been pilot tested and been the recipient of scrutiny in workshops taking place in Beijing, São Paulo, London, Dar es Salaam, New Delhi and Jakarta.
Key changes in this version apply to:
- Boundary setting and reporting levels, making it applicable to different scales and levels of data availability;
- Elaboration of calculation methods and procedures by individual sector, including guidance on data collection;
- Comparison with IPCC national inventory and other methodologies, enabling comparison and translation;
- Clarification on inventory aggregation, showing how data from many cities can be combined at national level to avoid double accounting.
Planning for climate action begins with developing a greenhouse gas inventory, the first step in determining where best to direct mitigation efforts and build a strategy to reduce overall emissions, then track the progress against targets.
Having such an inventory can also assist cities in meeting legal and voluntary requirements for reporting emissions. A growing number of cities are already doing so through various platforms such as the Carbon Disclosure Project and the carbonn Cities Climate Registry.
The protocol is an attempt to harmonise and make consistent all the various methods developed so far to permit greater credibility and encourage transparency. It also demonstrates the increasingly important role that cities play in tackling climate change, since cities are frequently able to take action and initiatives that are more progressive than their national governments.
Although it is primarily designed for cities the accounting framework may also be used for boroughs or wards within a city, town, district, county, prefecture, province or State. The protocol does not define what the geographic boundary is, that is up to the users.
Author | Title | Description |
|---|---|---|
IPCC | IPCC Guidelines for National Greenhouse Gas Inventories | Detailed guidance on GHG accounting for national inventories |
ICLEI | International Local Government GHG Emissions Analysis Protocol | Standards for community-level, and local government operations, GHG emissions |
UNEP, UN Habitat and World Bank | International Standard for Determining Greenhouse Gas Emissions for Cities | Simplified approach, with reference to other standards, such as IPCC Guidelines |
ICLEI-USA | U.S. Community Protocol for Accounting and Reporting of Greenhouse Gas Emissions | Provides U.S.-specific data sources, calculation approaches and reporting frameworks, from geographic to consumption based |
WRI and WBCSD | GHG Protocol Standards | Family of standards for GHG measurement and reporting for a variety of audiences and purposes (e.g., corporate, cities, projects) |
The Covenant of Mayors Initiative | Baseline Emissions Inventory / Monitoring Emissions Inventory methodology | Measures CO2 emissions resulting from non-EU ETS (emissions trading system) covered final energy consumption |
British Standards Institute | PAS 2070: Specification for the assessment of a city's greenhouse gas emissions | Measures GHG emissions using a direct plus supply chain, and consumption-based approach |
New York City
For example, New York City aims to reduce its greenhouse gas emissions by 30% below 2005 levels by 2030, and 80% by 2050. In order to do this the city conducts and publishes an annual assessment of its emissions. Its plan states that: "Regular, accurate data allow us to assess the impact of policy measures, infrastructure investments, consumer behaviour, population and whether on greenhouse gas emissions and focus our programmes to ensure that we are implementing the most effective mitigation strategies."
Results so far are encouraging: emissions were 19% lower in 2012 than in 2005. Reducing the carbon intensity of the city's electricity supply was found to make the most difference. The city plans to expand its inventory to map neighbourhood-level emissions the better to target policies and provide communities with information so they may contribute their part to reducing emissions.
The protocol asserts the value of including emissions outside of city boundaries where appropriate. It cites the example of the airport servicing Arendal, Norway, which is outside of the city's municipal boundaries but is nevertheless included in calculations since it is used by the city's inhabitants.
Key reporting principles
The key reporting principles are: relevance, completeness, consistency, accuracy and transparency. Trade-offs between these five principles may be required to set the boundaries of the procedures given that in some cases data may be more or less accurate.
As an example from a city in a developing country, Kampala, Uganda, in compiling its first greenhouse gas inventory in 2013 scaled or combined data from different years and sources to complete their calculations. For example, commercial activities were based on older data provided by the Uganda Investment Authority, while residential data was based on a household server tree from the inventory year.
Greenhouse gas emissions are categorised as Scope 1, 2 or 3 emissions based on an application of the Scopes framework used in the Greenhouse Gas Protocol Corporate Standard as follows:
Scope | Definition |
Scope 1 | All GHG emissions from sources located within the boundary of the city |
Scope 2 | All GHG emissions occurring as a consequence of the use of grid-supplied electricity, heating and/or cooling within the city boundary |
Scope 3 | All other GHG emissions that occur outside the city boundary as a result of activities within the city's boundary |
As regards sources, the protocol includes six main emission sectors which are categorised by scope these are: stationary energy, transportation, waste, industrial processes and product use (IPPU), agricultural, forestry and other land use (AFOLU), and other indirect emissions.
The figure below illustrates how some emission sources may occur solely within a geographic boundary but others may cross the boundaries.
There are three levels of reporting based on the quality of the available data: BASIC, BASIC+ and EXPANDED. These are characterised as follows:
- BASIC: All scope one sources, except those listed below, all scope to sources and waste sector Scope three sources. Do not include emissions from energy generation, in boundary disposal and treatment of imported waste, IPPU and AFOLU.
- BASIC+: All sources required for BASIC plus scope 1 emissions from AFOLU and IPPU and scope three emissions from transportation and stationary units. Emissions must not be estimated but if there are gaps in data these should be noted.
- EXPANDED: the above plus an expanded list of scope three sources. Not elaborated in this protocol but will be in future.
Feedback is required from all interested respondents by August 18.