Ethyl butyrate and its methylated derivatives are volatile and commonly used aroma compounds, yet their gas-phase chemistry and air quality impact remain poorly characterised. In this work, we investigated the reactivity of these compounds experimentally. We determined temperature-dependent rate coefficients for their reaction with the main atmospheric oxidant, OH, and found that this was the dominant tropospheric loss process. In contrast, direct photolysis is negligible under most conditions.

Triple oxygen isotopes (¹⁷O-excess) are an upcoming tool in hydrological studies. We present the first one-year high-resolution record of ¹⁷O-excess in atmospheric water vapor from a Mediterranean forest site. The dataset provides insights into the processes driving variability of ¹⁷O-excess in atmospheric water vapor and precipitation across seasonal, diurnal, and event scales. These findings support model validation efforts and enhance the interpretation of paleoclimate archives.

Using detailed numerical simulations, we quantify how stratocumulus cloud decks dissipate energy and produce entropy. We find that entropy production is dominated by irreversible moist processes and is much smaller than in deeper convective clouds. As a result, stratocumulus are remarkably inefficient at converting available energy into atmospheric motions.