CoMobility project data: Warsaw road traffic, road traffic emissions, and air concentrations for greater Warsaw area

Introduction

Data here are for the Greater Warsaw area, Poland originating in the CoMobility project. It contains data relevant to traffic activity, emissions, air quality and related health studies in the area. Files contain road properties along with traffic volume and rushhour delays as well as emissions of NOx, NO2 and PM from road traffic on individual road segment level. Also 500m gridded surface air concentrations are included for PM2.5 and PM10, and for NOx, NO2.

Data production

Roads are from the macroscopic traffic model MTAW (Warsaw Municipality, 2016) (Model Transportowy Aglomeracji Warszawskiej in Polish). It was developed based on the 2015 comprehensive travel survey in Warsaw and it is the main strategic transport model for the Greater Warsaw area, revised most recently in 2019. 

The NERVE model (Grythe et al, 2022), developed by NILU, provides detailed estimates of greenhouse gas and air pollutant emissions specifically from road traffic. Using a bottom-up approach, it combines data from regional traffic model (RTM), vehicle fleet composition, and emission factors from the Handbook Emission Factors for Road Transport (HBEFA). NERVE can be set up to calculate emissions at various levels, including road link, municipality, or national levels. It is a tool researchers and policymakers use this model for environmental assessments, policy decisions, and constructing different emission scenarios. Its high level of detail makes it valuable not only for practical emissions estimation but also as a research tool. Emissions for other sources came from the Central Emission Database by the Environmental Protection - National Research Institute (IEP-NRI) in Poland (Gawuc et al., 2021). The background concentrations were taken from the Copernicus Atmospheric Monitoring Services (CAMS) ensemble forecast for 2019 (Marécal et al., 2015)

The EPISODE model (Hamer et al. 2020), developed by NILU, is an Eulerian urban dispersion model designed to address the need for an accurate urban air quality model in support of policy, planning, and air quality management. EPISODE operates as a 3D grid model coupled with numerical weather prediction (NWP) data. It simulates dispersion from point and line sources to receptor points, with a focus on the photochemical production of ozone in urban areas. The model’s CityChem extension enhances its capabilities for complex pollution sources, incorporating numerical chemistry solvers, sub-grid photochemistry, and a simplified street canyon model. EPISODE serves as a valuable tool for understanding and managing air quality in urban environments.

Data files

The data on road traffic contains 60 084 road links that cover the Greater Warsaw area. The file input is a traffic file from the MTAW model and is processed and formatted with NREVE. The format is an ESRI shapefile with the following road parameters:

“DISTANCE” -length of road segment in kilometers.

“CAPACITY” -Hourly capacity of the road.

“SLOPE” -Vertical gradientor slope of the road (in %)

“SPEEDLIM” -Signed speed on the road (kilometers per hour)

In addition there are traffic volume parameters;

“ADT_LIGHT” – Annual Daily Traffic, light vehicles (personal cars + light duty vans) average derived from morning and evening peak hours 2019.

“ADT_HEAVY” – Annual Daily Traffic, heavy duty vehicles average derived from morning and evening peak hours 2019.

“ADT_BUSES” – Annual Daily Traffic, public transport buses average 2019.

“MRN_delay” – delay during morning rush hour peak (%)

“EVE_delay” – delay during evening rush hour peak (%)

The files also contain the annual emissions:

“EM_NOx” – 2019 annual emissions of NOx (gram).

“EM_ NO2” – 2019 annual emissions of NOx (gram).

“EM_PM” – 2019 annual emissions of NOx (gram).

EPISODE output files for atmospheric concentration files are given on NetCDF file format.  Concentrations are given as annual average grid concentration for each of the components. In addition, 42 000  spatially spread out receptor points gives the 2 meter concentrations to allow for surface air concentration levels at individual point locations. Furthermore, these allows for downgridding concentrations to higher resolution.

The source contribution files are from EPISODE and gives atmospheric concentration fields for NOx, PM10 and PM2.5 from individual sources. The individual sources are

“RDU” -Road dust (PM only)

“EXT” – Exhaust  (PM only)

“TRA” - Exhaust  (NOx only)

“IND” – Industry

“RES” – Residential

“OTH” – Other (all other sources within the domain combined )

“BGC” – Background (all sources outside the domain combined )