Project Details
Projekt
Retrieval, interpretation and dissemination of mini-DOAS data (O3, NO2, HONO, BrO, IO, OClO, CH2O, C2H2O2, and C3H4O2*) measured during previous HALO missions
Subject Area
Atmospheric Science
Term
since 2023
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 501886023
The proposal seeks support to further retrieve and interpret data (O3, NO2, HONO, BrO, IO, OClO, CH2O, C2H2O2, and C3H4O2*) measured by the mini-DOAS instrument during previous HALO missions. The mini-DOAS instrument is a passive remote sensing instrument for simultaneous measurements of Nadir and Limb scattered skylight in the UV/vis/NIR spectral ranges from aboard the research aircraft HALO. The measurements support the sensitive detection of in-situ concentrations, and remotely measured vertical profiles and total atmospheric column amounts of atmospheric trace gases not measurable (BrO, OClO, IO, C2H2O2, and C3H4O2*), or hardly measurable by other means (NO2, HONO, und CH2O). In addition, the measurements in the NIR provide means to simultaneously detect all three phases of H2O (liquid water and ice water path), some radiative properties of the atmosphere (e.g., relative radiances, and photon path length, …) and to collect information on the microphysical properties of aerosols and clouds. There are three major objectives within the present proposal: 1. the interpretation of simultaneously measured concentrations of BrO, OClO, O3, and NO2 (mini-DOAS), Cly and Cly* and of complementary parameters (the latter from other instruments on board HALO) during the POLSTRACC mission in Arctic winter 2015/2016, 2. the measurements of IO in the troposphere and lowermost stratosphere, and 3. the interpretation of simultaneously measured HONO (from the mini-DOAS instrument), NO and OH, the photolysis frequencies of HONO, NO2, and of complementary parameters measured during the CAFE-Africa mission in summer 2018. Objective 1 aims to study for the first time the inter-halogen ozone loss cycle as a function of chlorine activation from in-situ measured data and to infer total bromine in the lower stratosphere as function of air mass age, which may add further information to the bromine trend analysis performed by our research group since decades. Objective 2 may provide further information on the amount and occurrence of IO in the troposphere and lowermost stratosphere and its consequences for ozone, and lastly objective 3 may provide further insight on the amount of nitrous acid (HONO) formed by gas phase and heterogeneous processes and its contribution to HOx formation in aged polluted air masses.
DFG Programme
Infrastructure Priority Programmes
