What does the survey comprise?
To obtain data on the national atmospheric emissions by mobile sources.
Mobile sources, including foreign sources, on or above Dutch territory and on the Dutch part of the Continental Shelf. Mobile sources comprise means of transport (such as cars, lorries, inland vessels, and aircraft) and mobile machinery (such as agricultural tractors, forklift trucks, and (road) construction machinery) equipped with a combustion engine. The survey includes data on the emissions of CO, VOC (non-methane), NOx, PM10, SO2, CO2, CH4, N2O en NH3 as a result of combustion and evaporation of motor fuels and the wear of tyres, brake linings, road surfaces and overhead electrical wires.
Type of mobile source and/or transport.
First year of survey
Provisional figures are published 7 months after the year under review; definite are published about 12 months after the year under review.
The results of the survey are published in StatLine tables on emissions by mobile sources and on road traffic (in Dutch). They are also included in three StatLine tables (in English) on the total Dutch emissions into the atmosphere:
1. Emissions to the atmosphere: the actual emissions of all 9 substances (including by mobile sources).
2. IPCC emissions to the atmosphere: 3 greenhouse gases (CO2, CH4, N2O) calculated according to the IPCC protocol standards.
3. NEC emissions to the atmosphere: 5 substances which cause large scale air pollution (mainly substances causing acidification): non-methane VOC, NH3, NOx, SO2 and PM10 calculated according to the NEC standards.
Results are also published via the public website of the Dutch Emission Registration. An abstract of the emission data is also included in the CBS/PBL Compendium voor de Leefomgeving (Compendium for the human environment).
How is the survey carried out
Calculation on the basis of activity data and emission factors.
The activity data and emission factors are based on traffic and energy statistics, research, measurements, and a literature search. The report 'Methods for calculating the emissions of transport in the Netherlands' , which in principle is updated yearly, provides detailed technical information about the calculations.
The emission figures and activity data are provided by the institutes participating in the Emission Registration Project. In addition to Statistics Netherlands (CBS) the following institutes participate in this cooperation: the Dutch Environmental Assessment Agency (PBL), the Agricultural Economics Institute (LEI) and Alterra (both parts of Wageningen University and Research Centre), the Water Department of the DG for Public Works and Water Management, SenterNovem and TNO.
Checking and correction methods
How accurate are the data?
Because of the many different data sources used and determination methods for the basic data on the one hand and the complexity of the calculation on the other hand, it is not possible to express the accuracy of the various emission data in exact figures.
The publication 'Methods for calculating the emissions of transport in the Netherlands' describes the uncertainties in the emission calculations.
In general it can be stated that the sequential comparability is good, as the emission calculation has been systematically carried out in the same way every year. In order to obtain a consistent time series, in principle the complete time series is (re)calculated every year. In this way the latest knowledge, in particular about emission factors, can be incorporated in the calculation.
Plausibility control by means of a trend analysis. The determination of the emission figures takes place within the cooperation framework of the Dutch Emission Registration Project.