Introducing CRYOWRF v1.0: multiscale atmospheric flow simulations with advanced snow cover modelling Geoscientific Model Development DOI 10.5194/gmd-16-719-2023 10 March 2023 Most current generation climate and weather models have a relatively simplistic description of snow and snow–atmosphere interaction. One reason for this is the belief that including an advanced snow model would make the simulations too computationally demanding. In this study, we bring together two state-of-the-art models for atmosphere (WRF) and snow cover (SNOWPACK) and highlight both the feasibility and necessity of such coupled models to explore underexplored phenomena in the cryosphere. Read more
Investigating hydroclimatic impacts of the 168–158 BCE volcanic quartet and their relevance to the Nile River basin and Egyptian history Climate of the Past DOI 10.5194/cp-19-249-2023 8 March 2023 This work is a modeling effort to investigate the hydroclimatic impacts of a volcanic “quartet” during 168-158 BCE over the Nile River basin in the context of Ancient Egypt’s Ptolemaic era (305-30 BCE). The model simulated a robust surface cooling (~1.0-1.5°C), suppressing the African monsoon (deficit of >1mm day-1 over East Africa) and agriculturally vital Nile summer flooding. Our result supports the hypothesized relation between volcanic eruptions, hydroclimatic shocks, and societal impacts. Read more
Robust global detection of forced changes in mean and extreme precipitation despite observational disagreement on the magnitude of change Earth System Dynamics DOI 10.5194/esd-14-81-2023 6 March 2023 Precipitation change is an important consequence of climate change, but it is hard to detect and quantify. Our intuitive method yields robust and interpretable detection of forced precipitation change in three observational datasets for global mean and extreme precipitation, but the different observational datasets show different magnitudes of forced change. Assessment and reduction of uncertainties surrounding forced precipitation change are important for future projections and adaptation. Read more
Atmospheric boundary layer height from ground-based remote sensing: a review of capabilities and limitations Atmospheric Measurement Techniques DOI 10.5194/amt-16-433-2023 3 March 2023 Profile observations of the atmospheric boundary layer now allow for layer heights and characteristics to be derived at high temporal and vertical resolution. With novel high-density ground-based remote-sensing measurement networks emerging, horizontal information content is also increasing. This review summarises the capabilities and limitations of various sensors and retrieval algorithms which need to be considered during the harmonisation of data products for high-impact applications. Read more
Permafrost degradation and nitrogen cycling in Arctic rivers: insights from stable nitrogen isotope studies Biogeosciences DOI 10.5194/bg-20-365-2023 1 March 2023 Climate change is causing extensive permafrost degradation and nutrient releases into rivers with great ecological impacts on the Arctic Ocean. We focused on nitrogen (N) release from this degradation and associated cycling using N isotopes, an understudied area. Many N species are released at degradation sites with exchanges between species. N inputs from permafrost degradation and seasonal river N trends were identified using isotopes, helping to predict climate change impacts. Read more
Global evaluation of the “dry gets drier, and wet gets wetter” paradigm from a terrestrial water storage change perspective Hydrology and Earth System Sciences DOI 10.5194/hess-26-6457-2022 27 February 2023 Although the “dry gets drier, and wet gets wetter (DDWW)” paradigm is prevalent in summarizing wetting and drying trends, we show that only 11.01 %–40.84 % of the global land confirms and 10.21 %–35.43 % contradicts the paradigm during 1985–2014 from a terrestrial water storage change perspective. Similar proportions that intensify with the increasing emission scenarios persist until the end of the 21st century. Findings benefit understanding of global hydrological responses to climate change. Read more
Upwelled plankton community modulates surface bloom succession and nutrient availability in a natural plankton assemblage Biogeosciences DOI 10.5194/bg-19-5911-2022 24 February 2023 We investigated how different deep water chemistry and biology modulate the response of surface phytoplankton communities to upwelling in the Peruvian coastal zone. Our results show that the most influential drivers were the ratio of inorganic nutrients (N:P) and the microbial community present in upwelling source water. These led to unexpected and variable development in the phytoplankton assemblage that could not be predicted by the amount of inorganic nutrients alone. Read more
The IPCC Sixth Assessment Report WGIII climate assessment of mitigation pathways: from emissions to global temperatures Geoscientific Model Development DOI 10.5194/gmd-15-9075-2022 22 February 2023 Assessing hundreds or thousands of emission scenarios in terms of their global mean temperature implications requires standardised procedures of infilling, harmonisation, and probabilistic temperature assessments. We here present the open-source “climate-assessment” workflow that was used in the IPCC AR6 Working Group III report. The paper provides key insight for anyone wishing to understand the assessment of climate outcomes of mitigation pathways in the context of the Paris Agreement. Read more
Product distribution, kinetics, and aerosol formation from the OH oxidation of dimethyl sulfide under different RO2 regimes Atmospheric Chemistry and Physics DOI 10.5194/acp-22-16003-2022 20 February 2023 The atmospheric oxidation of dimethyl sulfide (DMS) is a major natural source of sulfate particles in the atmosphere. However, its mechanism is poorly constrained. In our work, laboratory measurements and mechanistic modelling were conducted to comprehensively investigate DMS oxidation products and key reaction rates. We find that the peroxy radical (RO2) has a controlling effect on product distribution and aerosol yield, with the isomerization of RO2 leading to the suppression of aerosol yield. Read more
Quantification of blue carbon in salt marshes of the Pacific coast of Canada Biogeosciences DOI 10.5194/bg-19-5751-2022 17 February 2023 Salt marshes are thought to be important carbon sinks because of their ability to store carbon in their soils. We provide the first estimates of how much blue carbon is stored in salt marshes on the Pacific coast of Canada. We find that the carbon stored in the marshes is low compared to other marshes around the world, likely because of their young age. Still, the high marshes take up carbon at rates faster than the global average, making them potentially important carbon sinks in the future. Read more