39690f3052054a60b22a67b4692cbfb4 English 8-bit variable size UCS Transfer Format, based on ISO/IEC 10646 7ca95b35d9e378c10343f2730a880549 dataset NCAS British Atmospheric Data Centre (NCAS BADC) +44(0)1235 446432 British Atmospheric Data Centre STFC Rutherford Appleton Laboratory Harwell Oxford OX11 0QX UK badc@rl.ac.uk pointOfContact 2026-04-16T02:10:34 UK GEMINI 2.3 WGS 84 MRF A756 ACTO flight: Airborne atmospheric and chemistry measurements taken on board the Met Office C-130 Hercules aircraft 2006-12-10T03:09:18 publication 2006-12-10T03:09:18 creation https://catalogue.ceda.ac.uk/uuid/39690f3052054a60b22a67b4692cbfb4 39690f3052054a60b22a67b4692cbfb4 NCAS British Atmospheric Data Centre (NCAS BADC) The Meteorological Research Flight (MRF) was a Met Office facility, which flew a well-instrumented C-130 Hercules aircraft for atmospheric research purposes. This dataset contains airborne atmospheric and chemistry measurements taken on board the Met Office C-130 Hercules aircraft flight A756 for the Atmospheric Chemistry and Transport of Ozone in the upper troposphere-lower stratosphere (UTLS) (ACTO) campaign. The flight was located over the North Atlantic. "Stratospheric Studies, with a low tropopause The tropopause was crossed in this experiment in order to study true stratospheric air with the available instrumentation. Ozone mixing ratios of up to 400ppb were measured and the corresponding CO mixing ratios were around 30 ppb. The discrimination between the two NOy channels was quite apparent: indicating a clear presence of HNO3. PAN was just detectable in this air. On descending back below the tropopause, at around 22,000ft, it was noted that the NOy channel, with the Rosemount inlet, was suddenly found to measure more NOy than the other NOy channel. This correlated better with a change in humidity than with the change in temperature. It has been suggested that the change in conditions causes nitrogen compounds (HNO3?) to be 'flushed off' the inlet. Suggestions have been made to change the inlet to the make it identical to the other inlet (backward facing PFA). The instruments generally worked well. There were some problems with the peroxide, as the flows were very poor, at FL270 and above, and the formaldehyde was measuring high values, thought to be due to a leak in the inlet line. The carbon monoxide instrument showed good anti-correlation with the ozone, after the first run at FL250 (when there were problems due to blockages affecting the flow to the optical filter). It was observed that the HORACE reading is high by about 15 ppb relative to the PC reading. Meteorology The situation was dominated by a low pressure system centred over Ireland (centre pressure 1000mb). The associated low tropopause made the situation ideal for studying stratospheric chemistry with the C-130. Met Office author 0370 900 0100 Met Office FitzRoy Road Exeter EX1 3PB enquiries@metoffice.gov.uk author Barjat, Hannah Unavailable author Unavailable author Brough, Neil Unavailable author Unavailable author Penkett, Stuart A. Unavailable author Unavailable author Carney, R. Unavailable author Unavailable author Lewis, Alastair C. Unavailable author Unavailable author Methven, John Unavailable author Unavailable author McQuaid, Jim Unavailable author Unavailable author Phillips, G.J. Unavailable author Unavailable author Purvis, Ruth Mary Unavailable author Unavailable author Reeves, Claire E. Unavailable author Unavailable author NCAS British Atmospheric Data Centre (NCAS BADC) custodian +44(0)1235 446432 British Atmospheric Data Centre STFC Rutherford Appleton Laboratory Harwell Oxford OX11 0QX UK badc@rl.ac.uk custodian NCAS British Atmospheric Data Centre (NCAS BADC) distributor +44(0)1235 446432 British Atmospheric Data Centre STFC Rutherford Appleton Laboratory Harwell Oxford OX11 0QX UK badc@rl.ac.uk distributor Penkett, Stuart A. Unavailable principal_investigator Unavailable principalInvestigator NCAS British Atmospheric Data Centre (NCAS BADC) point_of_contact +44(0)1235 446432 British Atmospheric Data Centre STFC Rutherford Appleton Laboratory Harwell Oxford OX11 0QX UK badc@rl.ac.uk pointofContact NCAS British Atmospheric Data Centre (NCAS BADC) publisher +44(0)1235 446432 British Atmospheric Data Centre STFC Rutherford Appleton Laboratory Harwell Oxford OX11 0QX UK badc@rl.ac.uk publisher notPlanned dataset UTLS ACTO Chemistry temperature pressure wind atmospheric conditions theme GEMET - INSPIRE themes, version 1.0 2008-06-01 publication otherRestrictions Access to these data is available to any registered CEDA user. Please Login or Register for a CEDA account to gain access. otherRestrictions Under the following licence http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/, appropriate use of these data may fall under any use. This message is intended as guidance, always read the full licence. When using these data you must cite them correctly using the citation given on the CEDA Data Catalogue record. grid English climatologyMeteorologyAtmosphere -10.0 -3.0 55.0 60.0 2000-05-16T09:00:35 2000-05-16T11:23:55 Data are ASCII formatted NCAS British Atmospheric Data Centre (NCAS BADC) Data Center Contact +44(0)1235 446432 British Atmospheric Data Centre STFC Rutherford Appleton Laboratory Harwell Oxford OX11 0QX UK badc@rl.ac.uk distributor https://catalogue.ceda.ac.uk/uuid/39690f3052054a60b22a67b4692cbfb4 CEDA Data Catalogue Page Detail and access information for the resource information http://data.ceda.ac.uk/badc/ukmo-mrf/data/a756 DOWNLOAD Download Data download dataset Commission Regulation (EU) No 1089/2010 of 23 November 2010 implementing Directive 2007/2/EC of the European Parliament and of the Council as regards interoperability of spatial data sets and services 2010-12-08 Data collected by instruments on-board the MRF C-130 during flight A756. Data acquired by BADC for archiving during the ACTO project.