"To what extent was the Little Ice Age a result of a change in the thermohaline circulation?" project. This was a Natural Environment Research Council (NERC) RAPID Climate Change Research Programme project (Joint International Round - NE/C509507/1 - Duration 1 Aug 2005 - 31 Jul 2008) led by Dr Tim Osborn of the University of East Anglia, with co-investigators at the University of East Anglia and Royal Netherlands Meteorology Institute. The dataset collection contains various model experiment output used in an analysis of whether the Little Ice Age climate could have been generated by one or more of the following factors: a weakening of the Atlantic thermohaline circulation; the persistence of a generally negative North Atlantic Oscillation; or reduced radiative forcing (by increased volcanic activity, reduced solar insolation and lower greenhouse gas concentrations relative to the present). Rapid Climate Change (RAPID) was a £20 million, six-year (2001-2007) programme for the Natural Environment Research Council. The programme aimed to improve the ability to quantify the probability and magnitude of future rapid change in climate, with a main (but not exclusive) focus on the role of the Atlantic Ocean's Thermohaline Circulation.

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.

Land surface and marine surface observations data from the Met Office station network and other world wide stations as stored in the Met Office MIDAS database. Data are available for the period 1853 to present. The dataset comprises daily and hourly weather measurements, hourly wind parameters, max and min air temperatures, soil temperatures, sunshine duration and radiation measurements and daily, hourly and sub-hourly rain measurements, some climatology data and marine observations (including sea surface temperature, swell and wave associated parameters). This dataset collection supersedes the Met Office Land Surface Stations Dataset collection (1900-2000), also archived at the BADC.

"The Circulation, overflow, and deep convection studies in the Nordic Seas using tracers and models" project was a Natural Environment Research Council (NERC) RAPID Climate Change Research Programme project (Round 1 - NER/T/S/2002/00446 - Duration 1 Aug 2003 - 31 Oct 2006 ) led by Prof Andrew Watson of the University of East Anglia, also with co-investigators at the University of East Anglia. Dataset contains sources of water in the Greenland-Scotland overflows: recent tracer release and transient tracer observations, as well as the initiation of convection and its relation to submesoscale hydrodynamics. This dataset collection contains MIT General Circulation Model (MITgcm) ocean model basin and channel experiment outputs. The project investigated two aspects of the Nordic Seas circulation of importance to the North Atlantic meridional overturning circulation (MOC): (1) Sources of water in the Greenland-Scotland overflows: recent tracer release and transient tracer observations were used to constrain inverse models of the sources of Denmark Straits and Faroe-Bank channel overflow waters. (2) The initiation of convection and its relation to submesoscale hydrodynamics: very high-resolution non-hydrostatic models for the Central Greenland Sea were used to model recent observations, which show convection to be intimately related to local sub-mesoscale structure.: The objective was to develop improved descriptions of convection for use in OGCMs, to more accurately describe how the sinking branch of the MOC will be affected by changes in forcing. Rapid Climate Change (RAPID) was a £20 million, six-year (2001-2007) programme for the Natural Environment Research Council. The programme aimed to improve the ability to quantify the probability and magnitude of future rapid change in climate, with a main (but not exclusive) focus on the role of the Atlantic Ocean's Thermohaline Circulation.

The Atmospheric Chemistry Studies in the Oceanic Environment (ACSOE) OXIdising Capacity of the Ocean Atmosphere (OXICOA) Free Tropospheric Experiment (FREETEX) Gas and Aerosol Data from Jungfraujoch High Alpine Research Station contains measurements of chemical species implicated in the control of ozone (O3, NOx, NOy, HNO3, PAN, CO, HO2 + RO2, HCHO, VOCs, etc.), at the Jungfraujoch High Alpine Research Station (3,580m above sea level) over a five-week period in 1996 and again in 1998. Jungfraujoch is located in the lower free troposphere during winter and very often in spring and autumn, during which ozone concentration increases, making it an ideal location to study ozone and peroxy radical chemistry observed in the free troposphere.

The Quantifying the impact of BOReal forest fires on Tropospheric oxidants over the Atlantic using Aircraft and Satellites (BORTAS) project provides information on the connection between the composition and the distribution of biomass burning outflow, ozone production and loss within the outflow, and the resulting perturbation to oxidant chemistry in the troposphere. The BORTAS team sampled biomass burning outflow over the North Atlantic in summer 2011 the using Facility for Airborne Atmospheric Measurements (FAAM) BAe-146 aircraft. The data were then used to describe the observed chemistry within plumes and to quantify the impact of boreal fires on the North Atlantic region using a nested 3-D chemistry transport model. This dataset contains atmospheric aircraft and model data. Science Objectives of BORTAS: -Sample biomass burning outflow from boreal North America over the western boundary of the North Atlantic during summer 2011 using the FAAM BAe146 aircraft; -Describe observed chemistry within plumes by using the measurements to constrain the Master Chemical Mechanism (MCM), with particular attention to the NOy and organic chemistry; -Derive a reduced chemical mechanism suitable for a global Chemical Transport Model (CTM) that accurately describes chemistry within the plumes; -Quantify the impact of boreal forest fires on oxidant chemistry over the temperate and subtropical Atlantic using a nested 3-D chemistry transport model, driven by a subset of MCM chemistry and by assimilated field measurements; and -Detect, validate and quantify the impact of boreal biomass burning on global tropospheric composition using data from space-borne sensors. The FAAM airborne sampling element of the BORTAS project took place in July and August 2011.

This is a copy of The Berlin Stratospheric Data Series provided to the BADC by K. Labitzke and her collaborators (2002) as a CD from the Meteorological Institute, Free University Berlin. This data set contains temperature and geopotential height data on the 100, 50, 30, 10 mb pressure surfaces produced at the Meteorological Institute, Free University of Berlin, from radiosonde data and rocket observations. This data series also contains summer, winter and annual trends and variability of the data, climatological monthly mean temperature and geopotential height at 30 mb, and intercomparisons with other data series. There are also sections on the quasi-biennial oscillation (QBO) and the global signal of the 11-year sunspot cycle in the stratosphere.

Data from observations made at the Cape Verde Atmospheric Observatory (CVAO) which exists to advance understanding of climatically significant interactions between the atmosphere and ocean and to provide a regional focal point and long-term data. The observatory is based on Calhau Island of São Vicente Cape Verde at 16.848N, 24.871W, in the tropical Eastern North Atlantic Ocean, a region which is data poor but plays a key role in atmosphere-ocean interactions of climate-related and biogeochemical parameters including greenhouse gases. It is an open-ocean site that is representative of a region likely to be sensitive to future climate change, and is minimally influenced by local effects and intermittent continental pollution. The dataset collection contains mixing ratio measurements of Ozone, CO, ethane, propane, iso-butane, acetylene, iso-pentane, and halocarbons. Meteorological measurements (wind speed, wind direction, atmospheric pressure, air temperature, relative humidity, solar radiation, rainfall) and aerosol concentrations are also contained in the data set. The Cape Verde Observatory was previously used during the SOLAS (Surface Ocean / Lower Atmosphere Study) project, from which the present day continuous observations have evolved. As such the earlier SOLAS measurements are also included within this collection. Additionally, back trajectory plots for the site are also within this collection.

Quaternary QUEST was led by Dr Tim Lenton at UEA, with a team of 10 co-investigators at the Universities of Cambridge, Oxford, Reading, Leeds, Bristol, Southampton and at UEA. This dataset collection contains glacial and isotope model data. Over the last million years, the Earth has experienced a sequence of temperature oscillations between glacial and interglacial states, linked to variations in the Earth’s orbit around the sun. These climate oscillations were accompanied by changes in atmospheric CO2, but the fundamental reasons for this relationship are still unresolved. This project team aimed to compile a synthesis of palaeodata from sediments and ice cores, improve the synchronization of these records with each other, and use this greater understanding of the Earth’s ancient atmosphere to improve Earth system models simulating climate over very long timescales. A combined long-term data synthesis and modelling approach has helped to constrain some key mechanisms responsible for glacial-interglacial CO2 change, and Quaternary QUEST narrowed the field of ocean processes that could have caused glacial CO2 drawdown.

Anthropogenic influence on Upper Tropospher-Lower Stratosphere (UTLS) clouds and aerosol (CIRRUS) UTLS round 5 project led by Prof. Tom Choularton. The dataset contains the total number of Condensation Nuclei (CN), CCN, IN and the size distribution of optically active particles in clean and polluted air in the UTLS region over the UK, the number, size distribution, phase and morphology of droplets and crystals in cirrus cloud. Objectives -To measure the total number of Condensation Nuclei (CN), CCN, IN and the size distribution of optically active particles in clean and polluted air in the UTLS region over the UK. Assessment of their spatial distribution and their likely source based on tracer measurements and air mass history. -To use a unique suite of state of the art instruments to quantify the extent to which air mass history, and gas and particle loading can affect the microphysical properties of cirrus clouds in the UTLS region, in particular, the size distribution, phase and morphology of cloud particles. -To obtain estimates of HNO3 loss to cirrus clouds and the subsequent effect on the aerosol population after the cloud has evaporated using case studies involving one or more wave clouds. -To make observations of the number, size distribution, phase and morphology of droplets and crystals in cirrus cloud and the number and size distribution of interstitial particles and correlate these with measurements of tracers that identify anthropogenic anthropogenic influence. Hence building on objective 3 to investigate the influence of cirrus on the distribution of aerosol and gases in the UTLS region as cloud and precipitation evaporate. -To make an assessment of the chemical composition of the particulate in the UTLS region as a function of their size, their spatial variability and the effect different sources have on their composition. -To use measurements of the masses of key components as a function of size of cirrus particle dry residues and interstitial particles to determine if there are distinct chemical differences between activated and unactivated particles. -To establish the partitioning of oxidised nitrogen between the gas and aerosol phases as a function of air mass history and source region. Methodology These studies were performed during the spring/summer of 2005 over the UK using the BAE 146 aircraft for in situ sampling Experiments were undertaken in a wide range of meteorological conditions i.e. in frontal cirrus, in convective conditions and in anticyclonic conditions. The aircraft made measurements below and within the cirrus cloud.