The National Inventory Report 2013 (NIR 2013) gives a detailed and com-prehensive description of the methodology applied in the Austrian air emissions inventory for the greenhouse gases of the “Kyoto basket” (carbon dioxide, methane, nitrous oxide, HFC, PFC and SF6). With this report, Austria complies with its reporting obligations under the UNFCCC and the Kyoto Protocol by providing transparent and verifi-able documentation. It contains sector-specific emissions for the years 1990 to 2011, emission factors, activity data and basic data for emis-sion calculations as well as additional information relevant for repor-ting under the Kyoto Protocol. Moreover, the NIR 2013 provides docu-mentation of the national inventory system and quality assurance as performed by the accredited inspection body (ISO/IEC 17020) on emis-sion inventories. ES.1 Background Information on greenhouse gas inventories, climate change and supplementary information under Article 7, paragraph 1, of the Kyoto Protocol ES.1.1 Background information on climate change Climate in a narrow sense is usually defined as the average weather, or more rigorously, as the statistical description in terms of the mean and variability of relevant quantities over a period of time ranging from months to thousands or millions of years. It undergoes natural variability. Since industrialisation started some 150 years ago, mankind has been influencing the climate via the emission of greenhouse gases. In 1992, by adopting the United Nations Convention on Climate Change, the countries of the world came together to prevent dangerous effects of climate change. However, the Convention did not include binding commitments to limit GHG emissions. To go this step further the Kyoto Protocol was adopted in 1997: It sets binding emission limits for 37 industrialized countries. ES.1.2 Background information on greenhouse gas inventories To be able to evaluate the trend of greenhouse gas emissions, especially the progress in achieving the emission reduction goal, it is necessary to regularly compile an inventory of GHG emissions. The compilation of these inventories follows rules as agreed under the respective bodies of the UNFCCC and the Kyoto Protocol. ES.1.3 Background information on supplementary information under Article 7, paragraph 1, of the Kyoto Protocol Supplementary information to be submitted annually under the UNFCCC is necessary to determine compliance with the regulations of the Kyoto Protocol. This is in particular (i) information on emissions and removals from the land use, land use change and forestry (LULUCF) sector under the Kyoto Protocol, (ii) information on the national registry which is responsible for accounting of the emission and removal units of each Party, (iii) information on any changes that have occurred in the national system compared with the information reported in the last submission, and (iv) information on the minimization of adverse impacts in accordance with Article 3, paragraph 14. Emissions and removals from the KP-LULUCF sector as well as land- and activity-related information and specific information to be reported with regard to activities under Art. 3 paragraph 3 is given in Chapter 10. Information on changes in the national registry since submission 2010 relate to the security measures implemented (Chapter 13). With regard to the Austrian national system there were no major changes compared to last years inventory. Information on how Austria is striving, under Art. 3 paragraph 14 of the Kyoto Protocol, to implement its commitments (Art. 3 paragraph 1) in such a way as to minimize adverse effects on developing country Parties is provided in Chapter 13.1, covering measures undertaken to minimize negative impacts (according to paragraph 23 of the Annex to decision 15/CMP) for example with reference to the Austrian JI/CDM programme as well as information on how priority is given pursuant to paragraph 24 of the Annex to decision 15/CMP. How Austria strives to phase out market imperfections that run counter to the objectives of the Convention and what other actions have been taken in the context of Article 3 paragraph 14 respectively paragraph 24 of Decision 15/CMP is described in Chapter 13.1. ES.2 Summary of National Emission and Removal Related Trends, and emission and removals from KP-LULUCF activities