ALBERT

Beschreibung: 〈jats:p〉Abstract. Aerosol particles are essential constituents of the Earth's atmosphere, impacting the earth radiation balance directly by scattering and absorbing solar radiation, and indirectly by acting as cloud condensation nuclei. In contrast to most greenhouse gases, aerosol particles have short atmospheric residence times, resulting in a highly heterogeneous distribution in space and time. There is a clear need to document this variability at regional scale through observations involving, in particular, the in situ near-surface segment of the atmospheric observation system. This paper will provide the widest effort so far to document variability of climate-relevant in situ aerosol properties (namely wavelength dependent particle light scattering and absorption coefficients, particle number concentration and particle number size distribution) from all sites connected to the Global Atmosphere Watch network. High-quality data from almost 90 stations worldwide have been collected and controlled for quality and are reported for a reference year in 2017, providing a very extended and robust view of the variability of these variables worldwide. The range of variability observed worldwide for light scattering and absorption coefficients, single-scattering albedo, and particle number concentration are presented together with preliminary information on their long-term trends and comparison with model simulation for the different stations. The scope of the present paper is also to provide the necessary suite of information, including data provision procedures, quality control and analysis, data policy, and usage of the ground-based aerosol measurement network. It delivers to users of the World Data Centre on Aerosol, the required confidence in data products in the form of a fully characterized value chain, including uncertainty estimation and requirements for contributing to the global climate monitoring system. 〈/jats:p〉

Beschreibung: Cruise SO288 served two scientific projects. The main objective of the COMBO project was the recovery of three seafloor geodetic networks of the GeoSEA array which were installed on the continental margin and outer rise offshore Iquique in northern Chileduring RV SONNE cruise SO244. This work was flanked by additional seismic and bathymetric surveys to characterize the sub-seafloor structure. The South American subduction system around 21°S has last ruptured in an earthquake in 1877 and wasidentified as a seismic gap prior to the 2014 Iquique earthquake (Mw=8.1). The southern portion of the segment remains unbroken by a recent earthquake and is currently in the latest stage of the interseismic phase of the seismic cycle. The seafloor geodetic measurements of the GeoSEA array provide a way to monitor crustal deformation at high resolution comparable to the satellite-based GPS technique upon which terrestrial geodesy is largely based. The GeoSEA array consists of autonomous seafloor transponders installed on 4 m high tripods. The transponders within an array intercommunicate via acoustic signals for a period of up to three years. Recovery of the GeoSEA array using a remotely operated vehicle (ROV KIEL6000) required dedicated dives in the three network locations on the middle and lower continental slope (AREA1 and AREA3, respectively) and the outer rise of the Nazca plate (AREA2). All 23 GeoSEA transponders were successfully recovered and showed an 100% uptime during the monitoring period.The GeoSEA survey represents the first seafloor geodetic transect across a subduction zone, spanning from the oceanic outer rise to the lower and middle slope of the continental upper plate. The second project, HOMER, focused on biogeochemical and microbiological processes that affect carbon cycling of the Humboldt Current System off Northern Chile down to the deep ocean. For this purpose, water samples were collected for the detailed chemical characterization of organic matter and the activity of microorganisms. The work was complemented by onboard incubations of microbial populations from deep waters with naturally occurring organic matter.Cruise SO288 was the first expedition of RV SONNE back to the Pacific Ocean starting from a South American port during the COVID-19 pandemic. Despite strict safety and health requirements prior to boarding RV SONNE in Guayaquil, several members of the scientific and ship’s crew tested positive to COVID-19 two days after we left port. Containment measures were immediately put to action, flanked by a tight testing regime. Ten days after leaving Guayaquil, we were able to break the chains of infection and the scientific working program commenced.

Beschreibung: 〈jats:p〉Abstract. We present a global atlas of downcore foraminiferal oxygen and carbon isotope ratios available at https://doi.org/10.1594/PANGAEA.936747 (Mulitza et al., 2021a). The database contains 2106 published and previously unpublished stable isotope downcore records with 361 949 stable isotope values of various planktic and benthic species of Foraminifera from 1265 sediment cores. Age constraints are provided by 6153 uncalibrated radiocarbon ages from 598 (47 %) of the cores. Each stable isotope and radiocarbon series is provided in a separate netCDF file containing fundamental metadata as attributes. The data set can be managed and explored with the free software tool PaleoDataView. The atlas will provide important data for paleoceanographic analyses and compilations, site surveys, or for teaching marine stratigraphy. The database can be updated with new records as they are generated, providing a live ongoing resource into the future. 〈/jats:p〉