WMO UNEP INTERGOVERNMENTAL PANEL ON CLIMATE CHANGE NATIONAL GREENHOUSE GAS INVENTORIES PROGRAMME WMO UNEP Direct / Indirect Jim Penman Simon Eggleston

Technical Support Unit, National Greenhouse Gas Inventory Programme, IPCC 2 CO 2 – The problem  CO 2 enters atmosphere either as CO 2 directly emitted “direct” CO 2 Or as oxidation of other C containing gases (e.g. CH 4, CO, NMVOC)  Existing Guidance Fuel emissions are based on C content of fuel – e.g. ALL C emitted as gas – Direct + Indirect CO 2 (“total”). Other sectors just have guidance for direct CO 2. Biogenic carbon sources have NO indirect CO 2

Technical Support Unit, National Greenhouse Gas Inventory Programme, IPCC Guidelines  In order to reduce changes from existing guidelines Fuel Combustion will be reported as before. Other Sources should report Direct and Total (Direct + Indirect CO 2 ) Biogenic C sources have CH 4 etc but NO indirect CO 2 as it is part of a closed biological cycle.  Guidance on CH4 is there but no extra guidance for CO and NMVOC is anticipated (reference will be made to other sources of guidance)  It is not expected that this will be a major source  Most developed countries already have inventories of CO and NMVOC

Technical Support Unit, National Greenhouse Gas Inventory Programme, IPCC 4 Indirect N 2 O  Existing guidelines for agriculture give methods for estimating emissions of N 2 O caused by the deposition of emitted NO x and NH 3 – “indirect N 2 O”  Guidance given for Agriculture only  Clearly other emissions of NO x and NH 3 cause indirect N 2 O

Technical Support Unit, National Greenhouse Gas Inventory Programme, IPCC 5 Nitrogen Transport  Complex and difficult to estimate deposition  Measurements also need to be extensive, long term and expensive.  EMEP (UNECE) programme in Europe is an example

Technical Support Unit, National Greenhouse Gas Inventory Programme, IPCC 6

7 An alternative  All N emitted is deposited  Apply emission factor to Emissions (as all emissions are deposited somewhere)  Allocate indirect N 2 O emissions to cause of the emission  Approach is simple and verifiable.

Technical Support Unit, National Greenhouse Gas Inventory Programme, IPCC 8 County % of totalGreenhouse gases% of Direct N2O Austria 1.11%16% Belgium 0.81%10% Czech Republic 0.95%17% Denmark 1.40%12% Finland 1.32%13% France 1.25%9% Germany 0.64%12% Ireland 0.94%7% Lithuania 1.97%6% Netherlands 0.83%12% Portugal 1.63%23% Spain 1.54%21% Sweden 2.33%13% United Kingdom 1.01%17% Canada 0.3%2.9% New Zealand 1.0%6.2% Japan 0.3%10.7% United States of America 0.7%11.0% Australia 1.1%17.1% Russian Federation 0.8%36.8%