This dataset collection contains air quality data from the Air Pollution & Human Health in a Developing Indian Megacity (APHH-India) programme 'Megacity Delhi atmospheric emission quantification, assessment and impacts (DelhiFlux)'.

This dataset contains volatile organic compound (VOC) fluxes recorded during two intensive field campaigns in Beijing (winter: 12/11/2016 - 10/12/2016; and summer: 15/05/2017 - 24/06/2017) as part of the Atmospheric Pollution & Human Health in a Chinese Megacity (APHH) programme. VOC concentrations were recorded using the GIG: Proton Transfer Reaction-Time of Flight- Mass Spectrometer (PTR-ToF-MS). Measurements were made at 102 m on the Institute of Atmospheric Physics (IAP) meteorological mast. Fluxes were processed by Lancaster University.

This dataset contains photolysis rate measurements made during the Pre- Monsoon and Post-Monsoon periods of the APHH Delhi campaigns in 2018 at Indira Gandhi Delhi Technical University for Women (IGDTUW) site. Photolysis rates are derived from the product of the absorption cross-section of the precursor molecule, the quantum yield of the photo-product and the actinic flux density (cm-2s-1nm-1). The actinic flux is measured between 280 - 650 nm (<1 nm resolution) using a Ocean Optics spectral radiometer attached to a quartz receiver optic. Data is averaged to 1 minute time-stamp. The data were collected as part of the DelhiFlux project part of Air Pollution & Human Health in a Developing Indian Megacity (APHH-India) programme.

This dataset contains direct infusion ultra-high resolution mass spectrometry measurements made at the Institute of Atmospheric Physics land station, Beijing (IAP-Beijing) site during the summer and winter APHH-Beijing campaign for the Atmospheric Pollution & Human Health in a Chinese Megacity (APHH) programme. Daily quartz microfiber filters were collected with a Tisch high volume sampler. The extracted organic fraction of the collected PM2.5 particles was analysed using an LTQ Orbitrap Velos mass spectrometer with electrospray ionisation to obtain high resolution mass spectra which enable the assignment of molecular formulae to the detected masses. For both seasons, 10 filters were analysed, containing the 5 filters with the highest and lowest mass loadings for each season. The files names are labeled according to the ID of the analysed filter. All dates and times are given in Beijing local time.

This dataset contains hourly online measurements of VOC mixing ratios using Gas Chromatography with Flame Ionisation Detector (GC-FID) at Indira Gandhi Delhi Technical University for Women (IGDTUW), Dehli, India. Mixing ratios are reported in parts per billion by volume (ppbV). The stationary inlet was located on the roof of a single-story building. This data was collected over two measurements periods (28/05/2018 - 05/06/2018 and 05/10/2018 - 27/10/2018), for the APHH-India DelhiFlux project, by the University of York. Data analysis was completed by Beth Nelson and Jim Hopkins at the University of York. Mixing ratios for the following species are included: ethane, ethene, propane, propane, iso-butane, n-butane, acetylene, trans-2-butene, 1-butene, iso-butene*, cis-2-butene, cyclopentane*, iso-pentane, n-pentane, 1,3-butadiene, trans-2-pentene, 1-pentene, n-octane, n-hexane, isoprene, n-heptane, benzene, toluene, ethylbenzene, combined m,p-xylene, o-xylene, methanol, acetone, ethanol, 1,2-butadiene*, propyne*. Date and time given in Local time as Julian day where 2018 01 01 = 0 Calibrations have been performed using a certified NPL 30 component mixture, and certified NPL 6 component mixture for o-VOC calibration. NOTE: any compound not contained therein has been assumed to have the same response factor as its closest isomer*. The data were collected as part of the DelhiFlux project part of Air Pollution & Human Health in a Developing Indian Megacity (APHH-India) programme.

This dataset contains black carbon concentrations using the aethalometer AE33 monitor. Measurements were made at the Indira Gandhi Delhi Technical University for Women (IGDTUW), India. Concentrations are reported in micrograms per cubic centimetre (ug.cm-3). The stationary inlet was located on the roof of a 4-storey building at IGDTUW campus. The data were collected over two measurement periods (i) winter: 17/01/2018 - 09/02/2018 and (ii) pre-monsoon: 02/05/2018 - 25/05/2018, by the University of Birmingham. These data were collected as part of the ASAP-Delhi project as part of the Atmospheric Pollution and Human Health in an Indian Megacity (APHH) programme.

This dataset contains ionic data within PM2.5 measurements made during the Pre- Monsoon (28/05/2018 08:30:00 - 05/06/2018 17:30:00) and Post-Monsoon periods (09/10/2018 14:54:00 - 0 6/11/2018 10:35:00) of the APHH Delhi campaigns in 2018 at Indira Gandhi Delhi Technical University for Women (IGDTUW) site. Measurements were conducted by the University of York High Volume Sampler (Ecotech 3000, Australia) and University of York Dionex ICS-1100 Ion Chromatography System. The data were collected as part of the DelhiFlux project part of Air Pollution & Human Health in a Developing Indian Megacity (APHH-India) programme.

This dataset contains Black carbon (BC) concentrations in ugm-3 measured with an Aethalometer model AE31 made during the Pre- Monsoon and Post-Monsoon periods of the APHH Delhi campaigns in 2018 at Indira Gandhi Delhi Technical University for Women (IGDTUW) site. The data has been corrected following the Weingartner method. Absorption coefficients were calculated following the Sandradewi model to determine biomass burning and fossil fuel contributions in Mm-1. The measurements were collected at a height of 4m. The data were collected as part of the DelhiFlux project part of Air Pollution & Human Health in a Developing Indian Megacity (APHH-India) programme.

This dataset contains hourly VOC concentration measurements from the University of York's two-dimensional gas chromatography with flame ionisation detection instrument. This instrument was located at the Indira Gandi Delhi Technical University for Women (IGDTUW). Mixing ratios are reported in parts per billion by volume (ppbV). The stationary inlet was located on the roof of a single-story building. Calibrations have been performed using a certified NPL 30 component mixture. Certain C4 substituted monoaromatic compounds have been tentatively identified. Monoterpenes have been quantified based on their relative response to liquid injections. The data were collected as part of the DelhiFlux project part of Air Pollution & Human Health in a Developing Indian Megacity (APHH-India) programme.

This dataset contains volatile organic compound concentration measurements made by the University of Lancaster using the UK CEH proton transfer reaction-quadrupole ion guide time of flight-mass spectrometer (PTR-QiTOF-MS). Measurements were made at the Indira Gandhi Delhi Technical University for Women (IGDTUW) field site, Dehli, India during the DelhiFlux campaigns. Measurements from 04/10/2018 to 04/11/2018 were made at ground level (~4 m). Measurements from 05/11/2018 to 23/11/2018 were made at 30 m above ground level. All values are reported in ppbV (parts per billion by volume). The data were collected as part of the DelhiFlux project part of Air Pollution & Human Health in a Developing Indian Megacity (APHH-India) programme.