Marine atmosphere oxidation capacity experiment

Projektinformationen

ID Finanzhilfevereinbarung: ENV4950004

Startdatum 1 Februar 1996

Enddatum 31 Juli 1998

Finanziert unter

• Specific programme of research and technological development in the field of environment and climate, 1994-1998

Gesamtkosten € 0,00

EU-Beitrag Keine Daten

Koordiniert durch

Forschungszentrum Jülich GmbH
Germany

Ziel

To investigate the self-cleansing ability of the troposphere through the determination of the concentration of free hydroxyl


A measurement campaign onboard the German research vessel POLARSTERN will be performed to measure
the latitudinal distribution of the OH radical concentration in the marine boundary layer (MBL) over the
Atlantic Ocean. The comparison of measured data with the predictions of a tropospheric OH photochemistry
model provides an ultimate test of this model. The measured OH data will be used for the assessment of the
oxidation of dimethyl sulphide (DMS) which is the dominant sulphur containing gas in surface marine waters.
The proposed project will investigate the OH induced formation of the DMS oxidation products SO2,
methanesulphonic acid (MSA), and non-sea-salt sulphate (nss-SO4) and the role they play in the formation of
submicrometer aerosol particles in the MBL. These aerosol particles strongly affect the global radiation budget;
the climate forcing due to sulphate aerosols is currently estimated to be comparable to that of greenhouse gases
but opposite in sign.
The project tasks are:
-Measurement of the concentration of OH radicals and their latitudinal distribution in the MBL over
the Atlantic Ocean during a ship cruise using laser long-path absorption spectroscopy.
-Simultaneous measurements of parameters important in controlling the OH concentration, including O3,
H2O, NO, NO2, NOy, CO, CH4, PAN, H2O2, HCHO, CH3CHO, NMHC,
photolysis rates, and
meteorological parameters.
-Test and improvement of a box model used for the description of the fast OH photochemistry. Model
studies of the sensitivity of the OH concentration to anthropogenic perturbations in the remote MBL.
-Determination of the oceanic source strength and the OH controlled lifetime of DMS in the MBL.
-Assessment of the role of DMS oxidation products in the formation of sub-micrometer aerosol particles
and cloud condensation nuclei.
-Evaluation of the impact of transport on the measured distribution of trace gases, nss-S04, and MSA
concentrations using a 3-D transport chemistry model.

Wissenschaftliches Gebiet

• natural sciences › chemical sciences › electrochemistry › electrolysis
• natural sciences › chemical sciences › physical chemistry › photochemistry
• natural sciences › physical sciences › optics › spectroscopy › absorption spectroscopy
• natural sciences › earth and related environmental sciences › atmospheric sciences › meteorology › troposphere
• natural sciences › physical sciences › optics › laser physics

Programm/Programme

• FP4-ENV 2C - Specific programme of research and technological development in the field of environment and climate, 1994-1998

Thema/Themen

• 01020102 - Tropospheric physics and chemistry

Aufforderung zur Vorschlagseinreichung

Data not available

Finanzierungsplan

CSC - Cost-sharing contracts

Koordinator

Forschungszentrum Jülich GmbH

• EU-Beitrag: Keine Daten
• Adresse: Wilhelm-Johnen-Straße ; 52425 Jülich ; Deutschland
• Gesamtkosten: Keine Daten

Beteiligte (1)

University of Crete

Griechenland

• EU-Beitrag: Keine Daten
• Adresse: Leoforos Knossou ; 71409 Heraklion
• Gesamtkosten: Keine Daten