Inventories.

I initially started off with a bit of chemistry; I have a habit of doing this as I enjoy the subject, so please bear with me if I repeat it in the future. I now will be focusing on sector based GHG emissions of UK (another field I have a fetish for) and adaptation strategies. One needs to understand that emissions come from various sources like fossil fuel combustion, most perceptible example but fossil fuels are used in many industries, transport, residential sectors (home appliances)etc. According to a report published by the Institute for European Environmental Policy (IEEP), the key drivers of these emissions are activity, economics (revolves around GDP), energy intensity (energy needed/required) and carbon intensity (amount of CO2 or CO2eq gases released).

To make a global inventory data (uniform statistics) all the regions (annex I and annex II) and all the sectors (energy, industry, waste etc.) need to be included. These are useful analytical inputs for policy making. Many international agencies like the IPCC, IEA, and UNFCCC have inventory fact sheets.

The manner in which the inventory is  complied is based on guidelines mentioned in various IPCC reports,  like the revised IPCC Guidelines for National Greenhouse Gas Inventories (IPCC, 1996), the Good Practice Guidance and Uncertainty Management in National Greenhouse Gas Inventories (IPCC, 2000), and the Good Practice Guidance for Land Use, Land-Use Change and Forestry (IPCC, 2003).

The activity data (use of fuel) in combination with the emissions factor (amount of CO2/CO2eq gases emitted per unit of the activity) help to make emission estimates.

The decrease in emissions in 2009 can be correlated with the effects of recession. While in 2010 (23percent less emissions than 1990) more than half the emissions are from the energy supply and transport sector.  

As per the UK GHG Inventory (UNFCCC coverage) (AEA, 2012) CO2 is the dominant GHG emitted, accounting for 85percent of emissions in 2010.

There may be errors in the inventory data factsheets (due to the vastness of the sectors) and so these are reviewed (annually) by UNFCCC experts or by the sector leads on the National Inventory Steering Committee (NISC).

Also past data from the current year (2012) inventory, projections of future emissions (variability in concentrations of a specific gas and these can be sector specific) can be made. For example Emissions (Energy Supply Sector) in 2025 are projected to be around 25.3% or 25.5% lower than in 2010 (based on Updated Energy and Emissions Projections: October 2011 (DECC) using historic data from the 2012 inventory).

The key data sources used in the compilation of the UK inventory are as follows:

-- Dept of Energy and Climate Change’s (DECC) Digest of UK Energy Statistics (DUKES).

-- The Pollution Inventory (Environment Agency), the Scottish Pollutant Release Inventory (SEPA) and the Inventory of Statutory Releases (Northern Ireland Dept of the Environment, DoE).

-- EU Emissions Trading System (ETS) operator returns.

-- Transport Statistics Great Britain (Dept for Transport, DfT).

-- Agriculture in the UK (Dept for Environment, Food and Rural Affairs,Defra).

-- Data supplied directly by plant operators.

-- Data supplied by Trade Associations.

-- Waste management data (Waste Data Flow).

-- LULUCF data from the Countryside Survey (Land Use, Land Use Change and Forestry).

It is difficult to obtain easily compileable data for all sectors; hence complex models have to be used as in the case of methane emissions from landfill sites. While the Industrial emission estimates have to be plant specific due to variability in activity and emission intensity.

In my next blogs I will focus on sector based emissions and then move on to the strategies (sector specific). I feel that the GHG emissions are a cause of our activities and so it is we who need to try and control our actions and use our technologies wisely.

References:

UUK GHG Inventory: http://ghgi.decc.gov.uk/

UK GHG National Statistics: http://www.statistics.gov.uk/hub/agriculture environment/environment/climate-change/index.html

UK Updated Energy Projections: http://www.decc.gov.uk/en/content/cms/about/ec_social_res/analytic_projs/en_emis_projs/en_emis_projs.aspx

 IPCC Guidelines http://www.ipcc-nggip.iges.or.jp/public/index.html