This dataset contains Organic aerosols, NO3-, SO4=, Cl- and NH4+ submicron concentrations in µg m-3 measured with High Resolution Time of Flight Aerosol Mass Spectrometer (HR-ToF-AMS) and Organic aerosol factors (Cooking Organic Aerosol (COA), Nitrogen-rich Hydrocarbon-like Organic Aerosol (NHOA), Solid-Fuel Organic Aerosol (SFOA), Hydrocarbon-like Organic Aerosol (HOA), Semi-Volatility Biomass Burning Organic Aerosol (SVBBOA), Low-Volatility Oxygenated Organic Aerosol (LVOOA), Semi-Volatility Oxygenated Organic Aerosol (SVOOA)) identified using positive matrix factorization. The instrument was located at the Indira Gandhi Delhi Technical University for Women (IGDTUW) from May to Nov 2018. The instrument sampled initially at 7 m above ground level, then was moved to 35 m above ground on the 5th of November 2018. The data were collected as part of the DelhiFlux project under the Air Pollution & Human Health in a Developing Indian Megacity (APHH-India) programme, and the UKCEH’s SUNRISE programme delivering National Capability to NERC.

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 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.

Southern Ocean Atmospheric Photochemistry Experiment 2 (SOAPEX-2) is primarily an experiment to study atmospheric cleansing by free radicals in extremely clean and slightly perturbed tropospheric air and focuses on a field campaign carried out at Cape Grim, Tasmania in January-February 1999. The dataset contains concentrations of seawater alkyl nitrates and halocarbons. This dataset is public.

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 online measurements of O3 mixing ratios using the commercially available Thermo 49i monitor. Measurements were made at the Indian Institute of Technology Delhi (IIT-Delhi), India. Mixing ratios are reported in parts per billion (ppb). The stationary inlet was located on the roof of a 5-storey building at Block IV, Indian Institute of Technology Delhi campus. The data were collected over three measurement periods (i) winter: 12/01/2018 - 13/02/2018, (ii) pre-monsoon: 26/04/2018 - 05/06/2018 and (iii) post-monsoon: 13/10/2018 - 10/11/2018, 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.

The CRYOspheric STudies of Atmospheric Trends in stratospherically and radiatively important gases (CRYOSTAT) will undertake the first combined measurements of virtually all significant Greenhouse gases (GHGs)(other than water vapour), ozone-depleting substances (ODSs), and related trace gases in contiguous firn and ice profiles, spanning as much as 200 years, from both the northern and southern polar ice caps. The dataset contains concentrations of isotopes (CH4, N20, CO, CO2, N20, SF6, CH3Br, halocarbons, and hydrocarbons) in firn, N2O concentrations in ice, ice core density, firn diffusivity, and weather measurements. CRYOSTAT is an evolution of the FIRETRACC/100 project, the data from which is also held at BADC.

Longterm observations (2002-present) of atmospheric chemistry parameters have been made at the Weybourne Atmospheric Observatory (WAO) including ozone, carbon monoxide and dulphur dioxide, oxides of nitrogen and cloud condensation nuclei. WAO is an NCAS facility and part of the School of Environmental Sciences at the University of East Anglia (UEA). It is situated on the north Norfolk coast and is a world class facility for fundamental research, background atmospheric monitoring and teaching purposes. WAO operates a range of instruments in its measurement programme - the data from which is archived at the BADC. The WAO has also been the focus of many international experiments designed to into the chemistry of the planetary boundary layer and free troposphere.

Tropospheric ORganic CHemistry Experiment (TORCH) was a Natural Environment Research Council (NERC) Polluted Troposphere Research Programme project (Round 1 - NER/T/S/2002/00145. Duration 2002 - 2005) led by A. Lewis, University of York. TORCH 1 took place in July and August 2003 at Writtle College, near Chelmsford, Essex. This dataset contains NMHC, O-VOC and DMS measurements by dual channel PTV-GC-FID.

Longterm Methane(CH4) measurements at the Weybourne Atmospheric Observatory (WAO) using Clarus 500 Greenhouse Gas GC (Perkin Elmer) instrument operated by the NCAS (National Centre for Atmospheric Science) AMF (Atmospheric Measurement Facility). WAO, situated on the north Norfolk coast, is part of the School of Environmental Sciences at the University of East Anglia (UEA) and is a world class facility for fundemental research, background atmospheric monitoring and teaching purposes. WAO operates a range of instruments in its measurement programme - the data from which is archived at the BADC. The atmospheric methane measurements are every 10 minutes.