How many modes are needed to predict climate bifurcations? Lessons from an experiment Nonlinear Processes in Geophysics DOI 10.5194/npg-29-17-2022 22 April 2022 Present climate models discuss climate change but show no sign of bifurcation in the future. Is this because there is none or because they are in essence too simplified to be able to capture them? To get elements of an answer, we ran a laboratory experiment and discovered that the answer is not so simple. Read more
Vegetation change across the Drake Passage region linked to late Eocene cooling and glacial disturbance after the Eocene–Oligocene transition Climate of the Past DOI 10.5194/cp-18-209-2022 20 April 2022 New pollen and spore data from the Antarctic Peninsula region reveal temperate rainforests that changed and adapted in response to Eocene climatic cooling, roughly 35.5 Myr ago, and glacially related disturbance in the early Oligocene, approximately 33.5 Myr ago. The timing of these events indicates that the opening of ocean gateways alone did not trigger Antarctic glaciation, although ocean gateways may have played a role in climate cooling. Read more
Representativeness assessment of the pan-Arctic eddy covariance site network and optimized future enhancements Biogeosciences DOI 10.5194/bg-19-559-2022 18 April 2022 Thawing of Arctic permafrost soils could trigger the release of vast amounts of carbon to the atmosphere, thus enhancing climate change. Our study investigated how well the current network of eddy covariance sites to monitor greenhouse gas exchange at local scales captures pan-Arctic flux patterns. We identified large coverage gaps, e.g., in Siberia, but also demonstrated that a targeted addition of relatively few sites can significantly improve network performance. Read more
The Whole Antarctic Ocean Model (WAOM v1.0): development and evaluation Geoscientific Model Development DOI 10.5194/gmd-15-617-2022 15 April 2022 Here we present an improved model of the Antarctic continental shelf ocean and demonstrate that it is capable of reproducing present-day conditions. The improvements are fundamental and regard the inclusion of tides and ocean eddies. We conclude that the model is well suited to gain new insights into processes that are important for Antarctic ice sheet retreat and global ocean changes. The model will ultimately help to improve projections of sea level rise and climate change. WAOM v1.0): development and evaluation">Read more
Rhizodeposition efficiency of pearl millet genotypes assessed on a short growing period by carbon isotopes (δ13C and F14C) SOIL DOI 10.5194/soil-8-49-2022 13 April 2022 Unravelling relationships between plant rhizosheath, root exudation and soil C dynamic may bring interesting perspectives in breeding for sustainable agriculture. Using four pearl millet lines with contrasting rhizosheaths, we found that δ13C and F14C of root-adhering soil differed from those of bulk and control soil, indicating C exudation in the rhizosphere. This C exudation varied according to the genotype, and conceptual modelling performed with data showed a genotypic effect on the RPE. Read more
Impact of increased resolution on long-standing biases in HighResMIP-PRIMAVERA climate models Geoscientific Model Development DOI 10.5194/gmd-15-269-2022 11 April 2022 Climate models do not fully reproduce observations: they show differences (biases) in regional temperature, precipitation, or cloud cover. Reducing model biases is important to increase our confidence in their ability to reproduce present and future climate changes. Model realism is set by its resolution: the finer it is, the more physical processes and interactions it can resolve. We here show that increasing resolution of up to ~ 25 km can help reduce model biases but not remove them entirely. PRIMAVERA climate models">Read more
Improved representation of agricultural land use and crop management for large-scale hydrological impact simulation in Africa using SWAT+ Hydrology and Earth System Sciences DOI 10.5194/hess-26-71-2022 8 April 2022 We present an approach on how to incorporate crop phenology in a regional hydrological model using decision tables and global datasets of rain-fed and irrigated cropland with the associated cropping calendar and management practices. Results indicate improved temporal patterns of leaf area index (LAI) and evapotranspiration (ET) simulations in comparison with remote sensing data. In addition, the improvement of the cropping season also helps to improve soil erosion estimates in cultivated areas. SWAT+">Read more
Arctic sea level variability from high-resolution model simulations and implications for the Arctic observing system Ocean Science DOI 10.5194/os-18-51-2022 6 April 2022 This study explores the Arctic sea level variability depending on different timescales and the relation to temperature, salinity and mass changes, identifying key parameters and regions that need to be observed co-ordinately. The decadal sea level variability reflects salinity changes. But it can only reflect salinity change at periods of greater than 1 year, highlighting the requirement for enhancing in situ hydrographic observations and complicated interpolation methods. Read more
Dependency of the impacts of geoengineering on the stratospheric sulfur injection strategy – Part 1: Intercomparison of modal and sectional aerosol modules Atmospheric Chemistry and Physics DOI 10.5194/acp-22-93-2022 4 April 2022 The use of different spatio-temporal sulfur injection strategies with different magnitudes to create an artificial reflective aerosol layer to cool the climate is studied using sectional and modal aerosol schemes in a climate model. There are significant differences in the results depending on the aerosol microphysical module used. Different spatio-temporal injection strategies have a significant impact on the magnitude and zonal distribution of radiative forcing and atmospheric dynamics. Read more
Not all biodiversity rich spots are climate refugia Biogeosciences DOI 10.5194/bg-18-6567-2021 1 April 2022 Biodiversity is under threat from the effects of global warming, and assessing the effects of climate change on areas of high species richness is of prime importance to conservation. Terrestrial and freshwater rich spots have been and will be less affected by climate change than other areas. However, marine rich spots of biodiversity are expected to experience more pronounced warming. Read more