ACCACIA was part of the NERC Arctic research programme. (NERC Reference: NE/I028858/1). ACCACIA aimed to improve our understanding of aerosol-cloud interactions in the Arctic, and the potential changes and feedbacks that may result from decreasing Arctic sea ice cover in the future. In situ measurements have been made during two field campaigns utilising ship-based measurements of surface aerosol sources and airborne measurements of aerosol and cloud microphysical properties, boundary layer dynamics, and radiative forcing. The observations have been complemented by modelling studies on a range of scales: from explicit aerosol and cloud microphysics process modelling, through large eddy simulation and mesoscale models, up to global climate models. This dataset contains meteorological data measured by the Meteorological Airborne Science INstrumentation (MASIN) onboard the British Antarctic Survey Twin Otter aircraft in the North Sea and Svalbard, Norway during the Aerosol Cloud Coupling and Climate Interactions in the Arctic (ACCACIA) project (2013).

ORCHESTRA is a NERC-funded Long Term Science programme that involves scientists from many NERC Centres. This 5 year project began in spring 2016 and will use a combination of data collection, analyses and computer simulations to radically improve our ability to understand and predict the circulation of the Southern Ocean and its role in the global climate, with particular emphasis on the way that the Southern Ocean absorbs and stores heat and carbon. This Collection provides the outputs of innovative model runs of the 1/12 degree Nucleus for European Modelling of the Ocean (NEMO) model of the Southern Ocean carried out within the project

High resolution radiosonde data from the British Antarctic Survey's stations Halley and Rothera are available. The data consists of vertical profiles of pressure, temperature, relative humidity, humidity mixing ratio, radiosonde position, wind speed and wind direction. Measurements are taken at 2 second intervals and the ascents extend to heights of approximately 20-30 km. The archive has data from 2001 and generally there is 1 ascent per day from both stations.

High resolution radiosonde data from the British Antarctic Survey's Rothera station. The data consists of vertical profiles of pressure, temperature, relative humidity, humidity mixing ratio, radiosonde position, wind speed and wind direction. Measurements are taken at 2 second intervals and the ascents extend to heights of approximately 20-30 km. The archive has data from 2008 and generally there is 1 ascent per day from the station.

High resolution radiosonde data from the British Antarctic Survey's Halley station. The data consists of vertical profiles of pressure, temperature, relative humidity, humidity mixing ratio, radiosonde position, wind speed and wind direction. Measurements are taken at 2 second intervals and the ascents extend to heights of approximately 20-30 km. The archive has data from 2008 and generally there is 1 ascent per day from the station.

The British Antarctic Survey (BAS) operated a Vaisala RS92 radiosonde unit at King Edward Point, South Georgia Islands to support meteor radar data also recorded at the site during the South Georgia Wave Experiment (SG-WEx) project. The sonde ascents took place during two campaigns: January 2015 and June/July 2015 to measure gravity waves. The data are standard radiosonde measurements of temperature, humidity, wind speeds, direction and pressure along the ascent at 10s intervals. These balloon ascents typically continue until the balloon fails in the stratosphere. The highest ascent recorded in these data was around 32km. Some ascents also provide data for parts of the descending part of the flight until the instrumentation failed. The King Edward Point Magnetic Observatory (KEP, 54.2820 S, 36.4930 W) is located on the South Georgia island in the South Atlantic.

In-situ airborne observations collected during flight 317 on 18 February 2019 by the Meteorological Airborne Science Instrumentation (MASIN) on board the British Antarctic Survey (BAS) Twin-otter aircraft for the ORCHESTRA - Ocean Regulation of Climate by Heat and Carbon Sequestration and Transports project. This dataset contains the core meteorological data from the MASIN instrument suite. Data were collected over the Falkland Islands area.

Airborne atmospheric measurements from core and non-core instrument suites data on board the British Antarctic Survey (BAS) Masin Twin-Otter aircraft collected for the Microphysics of Antarctic Clouds (MAC) project.

In-situ airborne observations collected during flight 319 on 23 February 2019 by the Meteorological Airborne Science Instrumentation (MASIN) on board the British Antarctic Survey (BAS) Twin-otter aircraft for the ORCHESTRA - Ocean Regulation of Climate by Heat and Carbon Sequestration and Transports project. This dataset contains the core meteorological data from the MASIN instrument suite. Data were collected over the Falkland Islands area.

In-situ airborne observations collected during flight 289 on 16 December 2017 by the Meteorological Airborne Science Instrumentation (MASIN) on board the British Antarctic Survey (BAS) Twin-otter aircraft for the ORCHESTRA - Ocean Regulation of Climate by Heat and Carbon Sequestration and Transports project. This dataset contains the core meteorological data from the MASIN instrument suite. Data were collected over the Antarctic Peninsula.