Greenhouse gases are produced and consumed via a number of pathways. Quantifying these pathways helps reduce the climate and environmental footprint of anthropogenic activities. The contribution of the pathways can be estimated from the isotopic composition, which acts as a fingerprint for these pathways. We have developed the Time-resolved FRactionation And Mixing Evaluation (TimeFRAME) model to simplify interpretation and estimate the contribution of different pathways and their uncertainty.

Ocean alkalinity enhancement (OAE) is an emerging marine CO₂ removal method, but its environmental effects are insufficiently understood. The OAE Pelagic Impact Intercomparison Project (OAEPIIP) provides funding for a standardized and globally replicated microcosm experiment to study the effects of OAE on plankton communities. Here, we provide a detailed manual for the OAEPIIP experiment. We expect OAEPIIP to help build scientific consensus on the effects of OAE on plankton.

Do-it-yourself hardware is a new way to improve measurement resolution. We present a low-cost, automated system for field measurements of low nitrate concentrations in soil porewater and open water bodies. All data hardware components cost USD 1100, which is much cheaper than other available commercial solutions. We provide the complete building guide to reduce technical barriers, which we hope will allow easier reproducibility and set up new soil and environmental monitoring applications.

Determination of dissolved greenhouse gas (GHG) in freshwater allows us to estimate GHG fluxes. Mercuric chloride (HgCl₂) is used to preserve water samples prior to GHG analysis despite its environmental and health impacts and interferences with water chemistry in freshwater. Here, we tested the effects of HgCl₂, two substitutes and storage time on GHG in water from two boreal lakes. Preservation with HgCl₂ caused overestimation of CO₂ concentration with consequences for GHG flux estimation.

We present a methodology to detect inconsistencies in perhaps the most important data source for measurements of ecosystem–atmosphere carbon, water, and energy fluxes. We expect that the derived consistency flags will be relevant for data users and will help in improving our understanding of and our ability to model ecosystem–climate interactions.

Coccolithophores contribute to the global carbon cycle and their calcite structures (coccoliths) are used as a palaeoproxy to understand past oceanographic conditions. Here, we compared three frequently used methods to estimate coccolith mass from the model species Emiliania huxleyi and the results allow for a high level of comparability between the methods, facilitating future comparisons and consolidation of mass changes observed from ecophysiological and biogeochemical studies.