RHaMBLe –Reactive Halogens in the Marine Boundary Layer

Gordon McFiggans (UMan), Martin Gallagher (UMan), Lucy Carpenter (UYork), John Plane (ULeeds), Dwayne Heard (ULeeds), William Bloss (ULeeds), Stephen Ball (ULeic)

 
RHaMBLe is an integrated programme aiming to quantify impacts of marine halogen emissions on atmospheric composition by the direct observation of a range reactive halogen species (RHS) in the marine atmosphere.  Emphasis is placed on the roles of halogens in oxidative processes and on secondary aerosol formation and transformations resulting from the cycling of RHS. RHaMBLe will extensively link to UK and internationally funded programmes to provide a package within UK SOLAS to link oceanic fluxes to atmospheric impacts.

 
RHaMBLe consists of two campaigns, one held in Roscoff, Brittany in July-August 2006 and the second in and around Cape Verde between 18^th May and the 15^th June 2007.   This webpage focuses on the second of these campaigns only.  Please contact Gordon McFiggans (g.mcfiggans@manchester.ac.uk) for details of the first campaign.   (Proposal)

Ground-based measurements

Ship measurements

 Ship plan- “To quantify marine halocarbon emission variability and latitudinal variation, characterise in situ open ocean atmospheric reactive iodine latitudinal variability and characterise oxidative chemistry perturbation due to oceanic emission of halogens from the Mauritanian upwelling region”

Prevailing meteorological conditions will be used to direct the cruise in terms of geographical positioning and measurement interpretation particularly:-

                - Exploitation of any broad flow connection between Cape Verde and the ship to interpret measurements as process studies

                - Identification of in- and out-of plume conditions to contrast chemistry influenced and uninfluenced by emissions from the upwelling region.

                                Fig 1.  MODIS 3-day composite of chl-a concentration for 25th-27th May                    Fig 2. Cruise track (superimposed on a zoom of Fig 1)  

During this campaign there was also a small aircraft campaign running simultaneously implementing the NERC Dornier 228 aircraft.    (Aircraft proposal)
The Dornier overflew the Discovery on the line of the first vertical gridline on Fig 2. 

 
Brief diary of events so far....

    11^th May-17^th May        Set-up week, Generator set-up for extra power at the site, instruments set-up on Discovery ship in Lisbon.

    18^th May                       Measurements begin at the atmospheric site,  Discovery ship sets sail from Lisbon.

                                        Aircraft campaign starts with a 3pm flight.

    26^th May                       Flight over Discovery (The Dornier flew over the line marked by blue squares on Fig 2 above).

    27^th May                       3 profile flights out from and above the atmospheric site,  9am, 1pm, 5pm.

    29^th May                       Flight over Discovery (The Dornier flew over the Discovery just after the turning point marked by 149 11:00 on Fig 2 above).

    30^th May                       3 profile flights.

    31^st May                       3 profile flights.

    1^st June                        3 profile flights.

    2^nd June                       3 profile flights.

    3rd June                        Aircraft campaign finishes, ground and ship campaign continue.

8-day back trajectories for the ground-based site:-   18/05/07   00:00     06:00     12:00     18:00        
                                                                                19/05/07   00:00     06:00     12:00     18:00
                                                                                20/05/07   00:00     06:00     12:00     18:00
                                                                                21/05/07   00:00     06:00     12:00     18:00
                                                                                22/05/07   00:00     06:00     12:00     18:00
                                                                                23/05/07   00:00     06:00     12:00     18:00
                                                                                24/05/07   00:00     06:00     12:00     18:00

Data

Core Data from the site for campaign

More data

Campaign Photos

Aircraft photos courtesy of Jim McQuaid