A multi-disciplinary analysis of the exceptional flood event of July 2021 in central Europe – Part 1: Event description and analysis Natural Hazards and Earth System Sciences DOI 10.5194/nhess-23-525-2023 20 March 2023 The flood event in July 2021 was one of the most severe disasters in Europe in the last half century. The objective of this two-part study is a multi-disciplinary assessment that examines the complex process interactions in different compartments, from meteorology to hydrological conditions to hydro-morphological processes to impacts on assets and environment. In addition, we address the question of what measures are possible to generate added value to early response management. Read more
The influence of elevated CO2 and soil depth on rhizosphere activity and nutrient availability in a mature Eucalyptus woodland Biogeosciences DOI 10.5194/bg-20-505-2023 17 March 2023 Elevated CO2 in the atmosphere increases forest biomass productivity when growth is not limited by soil nutrients. This study explores how mature trees stimulate soil availability of nitrogen and phosphorus with free-air carbon dioxide enrichment after 5 years of fumigation. We found that both nutrient availability and processes feeding available pools increased in the rhizosphere, and phosphorus increased at depth. This appears to not be by decomposition but by faster recycling of nutrients. Read more
Review article: Potential of nature-based solutions to mitigate hydro-meteorological risks in sub-Saharan Africa Natural Hazards and Earth System Sciences DOI 10.5194/nhess-23-481-2023 17 March 2023 In sub-Saharan Africa, there is reported uptake of at least one nature-based solution (NBS) in 71 % of urban areas in the region for mitigating hydro-meteorological risks. These NBSs are implemented where risks exist but not where they are most severe. With these NBSs providing multiple ecosystem services and four out of every five NBSs creating livelihood opportunities, NBSs can help address major development challenges in the region, such as water and food insecurity and unemployment. Read more
Slowdown of Shirase Glacier, East Antarctica, caused by strengthening alongshore winds The Cryosphere DOI 10.5194/tc-17-445-2023 15 March 2023 Satellite observations have shown that the Shirase Glacier catchment in East Antarctica has been gaining mass over the past 2 decades, a trend largely attributed to increased snowfall. Our multi-decadal observations of Shirase Glacier show that ocean forcing has also contributed to some of this recent mass gain. This has been caused by strengthening easterly winds reducing the inflow of warm water underneath the Shirase ice tongue, causing the glacier to slow down and thicken. Read more
Natural marine cloud brightening in the Southern Ocean Atmospheric Chemistry and Physics DOI 10.5194/acp-23-1677-2023 13 March 2023 The number of cloud droplets per unit volume is a significantly important property of clouds that controls their reflective properties. Computer models of the Earth’s atmosphere and climate have low skill at predicting the reflective properties of Southern Ocean clouds. Here we investigate the properties of those clouds using satellite data and find that the cloud droplet number and cloud albedo in the Southern Ocean are related to the oceanic phytoplankton abundance near Antarctica. Read more
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
