Exploring drought hazard, vulnerability, and related impacts on agriculture in Brandenburg Natural Hazards and Earth System Sciences DOI 10.5194/nhess-24-4237-2024 5 December 2024 Droughts are a threat to agricultural crops, but different factors influence how much damage occurs. This is important to know to create meaningful risk maps and to evaluate adaptation options. We investigate the years 2013–2022 in Brandenburg, Germany, and find in particular the soil quality and meteorological drought in June to be statistically related to the observed damage. Measurement of crop health from satellites is also related to soil quality and not necessarily to anomalous yields. Read more
Weak liquid water path response in ship tracks Atmospheric Chemistry and Physics DOI 10.5194/acp-24-13269-2024 5 December 2024 Ship emissions can form artificially brightened clouds, known as ship tracks, and provide us with an opportunity to investigate how aerosols interact with clouds. Previous studies that used ship tracks suggest that clouds can experience large increases in the amount of water (LWP) from aerosols. Here, we show that there is a bias in previous research and that, when we account for this bias, the LWP response to aerosols is much weaker than previously reported. Read more
Modeling 2020 regulatory changes in international shipping emissions helps explain anomalous 2023 warming Earth System Dynamics DOI 10.5194/esd-15-1527-2024 4 December 2024 On 1 January 2020, international shipping vessels were required to substantially reduce the amount of particulate they emit to improve air quality. In this work we demonstrate how this regulatory change contributed to the anomalous warming observed in recent months using climate model simulations that include such a change. Future policies should also perhaps consider their impact on climate, and climate modelers should promptly include those changes in future modeling efforts. Read more
Cross-scale causal information flow from the El Niño–Southern Oscillation to precipitation in eastern China Earth System Dynamics DOI 10.5194/esd-15-1509-2024 2 December 2024 The El Niño–Southern Oscillation (ENSO) is a gigantic natural orchestra playing with the temperature of Pacific waters and influencing air temperature and rainfall worldwide. Naturally, the “loudness” or amplitude of ENSO has effects on climate; however, consonance of its various tones, or phases of different ENSO oscillatory components, can exert causal effects on rainfall in some areas in China. In different regions, different aspects of ENSO dynamics can predict rainfall amounts. Read more
Microbial response to deliquescence of nitrate-rich soils in the hyperarid Atacama Desert Biogeosciences DOI 10.5194/bg-21-5305-2024 29 November 2024 We studied unique nitrate-rich soils in the hyperarid Atacama Desert that form brines at night under high relative humidity. Despite providing water for microorganisms, these soils exhibit extremely low microbial activity, indicating that the high nitrate levels inhibit microbial life. On the other hand, enriched organic matter indicates their potential preservation. This research helps to understand the limits of life in extreme environments and aids in the search for signs of life on Mars. Read more
Microbial strong organic-ligand production is tightly coupled to iron in hydrothermal plumes Biogeosciences DOI 10.5194/bg-21-5233-2024 29 November 2024 Hydrothermally derived iron can be transported kilometers away from deep-sea vents, representing a significant flux of vital micronutrients to the ocean. However, the mechanisms that support the stabilization of dissolved iron remain elusive. Using electrochemical, spectrometry, and genomic methods, we demonstrated that strong ligands exert an important control on iron in plumes, and high-affinity iron-binding siderophores were identified in several hydrothermal plume samples for the first time Read more
Representation of the terrestrial carbon cycle in CMIP6 Biogeosciences DOI 10.5194/bg-21-5321-2024 28 November 2024 This study investigates present-day carbon cycle variables in CMIP5 and CMIP6 simulations. Overall, CMIP6 models perform better but also show many remaining biases. A significant improvement in the simulation of photosynthesis in models with a nitrogen cycle is found, with only small differences between emission- and concentration-based simulations. Thus, we recommend using emission-driven simulations in CMIP7 by default and including the nitrogen cycle in all future carbon cycle models. Read more
Opinion: Beyond global means – novel space-based approaches to indirectly constrain the concentrations of and trends and variations in the tropospheric hydroxyl radical (OH) Atmospheric Chemistry and Physics DOI 10.5194/acp-24-13001-2024 28 November 2024 Trace gases emitted to or formed within the atmosphere may be chemically or physically removed from the atmosphere. One trace gas, the hydroxyl radical (OH), is responsible for initiating the chemical removal of many trace gases, including some greenhouse gases. Despite its importance, scientists have not been able to adequately measure OH. In this opinion piece, we discuss promising new methods to indirectly constrain OH using satellite data of trace gases that control the abundance of OH. Read more
Eddy covariance with slow-response greenhouse gas analysers on tall towers: bridging atmospheric and ecosystem greenhouse gas networks Atmospheric Measurement Techniques DOI 10.5194/amt-17-6625-2024 27 November 2024 This study presents direct flux measurements in tall towers using existing slow-response analysers and adding 3D sonic anemometers. This way, we can significantly improve greenhouse gas monitoring with little extra instrumental effort. Slow-response analysers may be used here as the relevant frequency ranges depend on measuring height. Tall towers offer a large footprint, amplifying spatial coverage. The presented concept is a valuable bridge between atmospheric and ecosystem communities. Read more
Invited perspectives: safeguarding the usability and credibility of flood hazard and risk assessments Natural Hazards and Earth System Sciences DOI 10.5194/nhess-24-4015-2024 26 November 2024 Flood risk assessments help us decide how to reduce the risk of flooding. Since these assessments are based on probabilities, it is hard to check their accuracy by comparing them to past data. We suggest a new way to validate these assessments, making sure they are practical for real-life decisions. This approach looks at both the technical details and the real-world situations where decisions are made. We demonstrate its practicality by applying it to flood emergency planning. Read more
X-BASE: the first terrestrial carbon and water flux products from an extended data-driven scaling framework, FLUXCOM-X Biogeosciences DOI 10.5194/bg-21-5079-2024 25 November 2024 The movement of water, carbon, and energy from the Earth’s surface to the atmosphere, or flux, is an important process to understand because it impacts our lives. Here, we outline a method called FLUXCOM-X to estimate global water and CO2 fluxes based on direct measurements from sites around the world. We go on to demonstrate how these new estimates of net CO2 uptake/loss, gross CO2 uptake, total water evaporation, and transpiration from plants compare to previous and independent estimates. Read more
Twenty-first century global glacier evolution under CMIP6 scenarios and the role of glacier-specific observations The Cryosphere DOI 10.5194/tc-18-5045-2024 18 November 2024 Glaciers are major contributors to sea-level rise and act as key water resources. Here, we model the global evolution of glaciers under the latest generation of climate scenarios. We show that the type of observations used for model calibration can strongly affect the projections at the local scale. Our newly projected 21st century global mass loss is higher than the current community estimate as reported in the latest Intergovernmental Panel on Climate Change (IPCC) report. Read more
How to measure the efficiency of bioenergy crops compared to forestation Biogeosciences DOI 10.5194/bg-21-5005-2024 15 November 2024 Using a state-of-the-art land model, we find that bioenergy plants can store carbon more efficiently than forests over long periods in the soil, in geological reservoirs, or by substituting fossil-fuel-based energy. Planting forests is more suitable for reaching climate targets by 2050. The carbon removal potential depends also on local environmental conditions. These considerations have important implications for climate policy, spatial planning, nature conservation, and agriculture. Read more
An overview of outdoor low-cost gas-phase air quality sensor deployments: current efforts, trends, and limitations Atmospheric Measurement Techniques DOI 10.5194/amt-17-6425-2024 12 November 2024 We reviewed 60 sensor networks and 17 related efforts (sensor review papers and data accessibility projects) to better understand the landscape of stationary low-cost gas-phase sensor networks deployed in outdoor environments worldwide. Gaps in monitoring efforts include the availability of gas-phase measurements compared to particulate matter (PM) and geographic coverage gaps (the Global South, rural areas). We conclude with a summary of cross-network unification and quality control efforts. Read more
Testing floc settling velocity models in rivers and freshwater wetlands Earth Surface Dynamics DOI 10.5194/esurf-12-1267-2024 11 November 2024 Fine sediment grains in freshwater can cohere into faster-settling particles called flocs, but floc settling velocity theory has not been fully validated. Combining three data sources in novel ways in the Wax Lake Delta, we verified a semi-empirical model relying on turbulence and geochemical factors. For a physics-based model, we showed that the representative grain diameter within flocs relies on floc structure and that heterogeneous flow paths inside flocs increase floc settling velocity. Read more
Tropospheric links to uncertainty in stratospheric subseasonal predictions Atmospheric Chemistry and Physics DOI 10.5194/acp-24-12259-2024 6 November 2024 Strong variations in the strength of the stratospheric polar vortex can profoundly affect surface weather extremes; therefore, accurately predicting the stratosphere can improve surface weather forecasts. The research reveals how uncertainty in the stratosphere is linked to the troposphere. The findings suggest that refining models to better represent the identified sources and impact regions in the troposphere is likely to improve the prediction of the stratosphere and its surface impacts. Read more
A three-stage model pipeline predicting regional avalanche danger in Switzerland (RAvaFcast v1.0.0): a decision-support tool for operational avalanche forecasting Geoscientific Model Development DOI 10.5194/gmd-17-7569-2024 31 October 2024 By harnessing AI models, this work enables processing large amounts of data, including weather conditions, snowpack characteristics, and historical avalanche data, to predict human-like avalanche forecasts in Switzerland. Our proposed model can significantly assist avalanche forecasters in their decision-making process, thereby facilitating more efficient and accurate predictions crucial for ensuring safety in Switzerland’s avalanche-prone regions. Read more
Exploring climate stabilisation at different global warming levels in ACCESS-ESM-1.5 Earth System Dynamics DOI 10.5194/esd-15-1353-2024 30 October 2024 Governments are targeting net-zero emissions later this century with the aim of limiting global warming in line with the Paris Agreement. However, few studies explore the long-term consequences of reaching net-zero emissions and the effects of a delay in reaching net-zero. We use the Australian Earth system model to examine climate evolution under net-zero emissions. We find substantial changes which differ regionally, including continued Southern Ocean warming and Antarctic sea ice reduction. Read more
Air quality modeling intercomparison and multiscale ensemble chain for Latin America Geoscientific Model Development DOI 10.5194/gmd-17-7467-2024 29 October 2024 Latin America (LAC) has some of the most populated urban areas in the world, with high levels of air pollution. Air quality management in LAC has been traditionally focused on surveillance and building emission inventories. This study performed the first intercomparison and model evaluation in LAC, with interesting and insightful findings for the region. A multiscale modeling ensemble chain was assembled as a first step towards an air quality forecasting system. Read more
Opinion: How will advances in aerosol science inform our understanding of the health impacts of outdoor particulate pollution? Atmospheric Chemistry and Physics DOI 10.5194/acp-24-11981-2024 28 October 2024 This opinion paper explores how advances in aerosol science inform our understanding of the health impacts of outdoor particulate pollution. We advocate for a shift in the way we target PM pollution, focusing on the most harmful anthropogenic emissions. We highlight key observations, modelling developments, and emission measurements needed to achieve this shift. Read more