Article
Geosciences, Multidisciplinary
Yuanpu Li, Sihua Huang, Zhiping Wen
Summary: This study investigated the influence of the stratospheric quasi-biennial oscillation (QBO) on the tropical easterly jet (TEJ). The results showed that QBO influences TEJ by affecting convection on the east and west sides of the Maritime Continent. During easterly QBO (EQBO), the easterlies of TEJ over the Maritime Continent are weaker, possibly due to the reduced stability near the tropopause during EQBO.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Meteorology & Atmospheric Sciences
Emily Bercos-Hickey, Christina M. Patricola
Summary: This study examines the changes in the African easterly jet and African easterly waves under future climate conditions, finding that the jet will be weaker and shifted northwards in the future, while the waves will increase in number and strength.
Article
Meteorology & Atmospheric Sciences
Dhana Lakshmi Douluri, Arun Chakraborty
Summary: This study investigates the simulation of heavy precipitation events over the West Coast of India associated with atmospheric rivers using the ARW-WRF model. The sensitivity of different parameterization schemes was evaluated, with deviations and advantages observed in the model simulations.
ATMOSPHERIC RESEARCH
(2021)
Article
Geosciences, Multidisciplinary
Hannah L. Croad, Jonathan K. P. Shonk, Amulya Chevuturi, Andrew G. Turner, Kevin I. Hodges
Summary: This study identifies the Indian Easterly Jet (IEJ) for the first time during the pre-monsoon season using reanalysis data. The IEJ is weaker and smaller than the African Easterly Jet and is associated with thermal wind and meridional gradients in temperature and moisture. The presence of the IEJ affects surface temperatures and precipitation in India. Further research on the IEJ's role in weather phenomena such as heatwaves, severe storms, and the monsoon onset is warranted.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Meteorology & Atmospheric Sciences
Vivekananda Hazra, Sandeep Pattnaik
Summary: This study evaluates the influence of five cloud microphysical parameterization schemes on simulations of Indian summer monsoon low-pressure systems. Results show that the choice of parameterization significantly impacts the characteristics of the monsoon depressions, such as rainfall, wind, temperature, moisture, and hydrometeors. Among the schemes tested, WRF Double moment stands out as the best performer in terms of rainfall forecast and representation of key meteorological variables.
INTERNATIONAL JOURNAL OF CLIMATOLOGY
(2021)
Article
Geosciences, Multidisciplinary
Yuanpu Li, Jadwiga H. Richter, Chih-Chieh Chen, Qi Tang
Summary: The Energy Exascale Earth System Model version 1 (E3SMv1) is able to generate a weakened tropical easterly jet (TEJ) during the easterly quasi-biennial oscillation (EQBO) and a strengthened TEJ during the westerly QBO (WQBO), known as the QBO-TEJ teleconnection. Despite the differences in the longitudinal structure of the QBO-TEJ teleconnection between reanalysis and simulations, it is hypothesized that simulations can still provide insights into the observed long-term changes in this teleconnection. The AMIP-historical simulations show a strengthened trend in the correlation between the QBO and TEJ indices from 1950 to 2014, similar to reanalysis. Comparison between AMIP-historical and coupled-historical simulations reveals the significant role of Indian Ocean warming in the strengthened QBO-TEJ teleconnection over the past six decades.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geosciences, Multidisciplinary
Leonore Jungandreas, Cathy Hohenegger, Martin Claussen
Summary: Coarse global climate models fail to reproduce the monsoonal precipitation pattern over North Africa during the mid-Holocene. The first regional, storm-resolving simulations with an idealized mid-Holocene vegetation cover show a northward shift of the West African monsoon and reduced precipitation gradient between the Guinea coast and the Sahara. Soil moisture and precipitation interactions, as well as land surface interactions with the monsoon circulation, are found to be responsible for the changes in monsoonal precipitation.
CLIMATE OF THE PAST
(2023)
Article
Meteorology & Atmospheric Sciences
Shibo Gao, Danlian Huang, Ningzhu Du, Chuanyou Ren, Haiqiu Yu
Summary: Ensemble dynamical downscaling of precipitation over China based on two different cumulus convective parameterization schemes showed superior performance in capturing the characteristics of precipitation patterns and improving the representation of both annual mean and interannual variations. The ensemble also demonstrated the highest skill in representing precipitation anomalies at regional scales for all subregions, as well as capturing the spatial patterns and temporal variations of dominant precipitation variability modes.
ATMOSPHERIC RESEARCH
(2022)
Article
Meteorology & Atmospheric Sciences
Ruifen Zhan, Yuqing Wang, Yihui Ding
Summary: This study examines the impact of the tropical easterly jet (TEJ) on tropical cyclone (TC) activity over the western North Pacific (WNP). The results show a significant positive correlation between the TEJ and TC genesis frequency, with an intensified TEJ leading to increased upward motion and low-level convergence favorable for TC genesis. Furthermore, the interannual variability of the TEJ intensity is linked to local diabatic heating and the central Pacific El Nino-Southern Oscillation.
ADVANCES IN ATMOSPHERIC SCIENCES
(2022)
Article
Meteorology & Atmospheric Sciences
Vivekananda Hazra, Sandeep Pattnaik
Summary: This study investigates the relationship between monsoon low-pressure systems (LPS) and rainfall, using different cloud microphysical parameterization methods and analyzing rainfall vulnerability and LPS intensity at a district scale in Odisha, India. The results show that the WDM6 method performs the best in terms of rainfall, and deep depressions (DD) are more thermodynamically efficient than depressions (MD) in converting latent energy to kinetic energy. The study also identifies distinct storm energetics characteristics in DD compared to MD.
QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY
(2023)
Article
Meteorology & Atmospheric Sciences
Jasti S. Chowdary, Amol S. Vibhute, Patekar Darshana, Anant Parekh, C. Gnanaseelan, Raju Attada
Summary: This study examines the impact of the meridional displacement of the Asian jet on Indian summer monsoon rainfall. The findings suggest that the southward displacement of the Asian jet leads to reduced precipitation over central and northern India regions. The study also reveals the physical mechanisms linking the southward displacement of the Asian jet and monsoon rainfall reduction.
Article
Geosciences, Multidisciplinary
Xiangbo Feng, Ralf Toumi, Malcolm Roberts, Kevin I. Hodges, Pier Luigi Vidale
Summary: Attributing sources of tropical cyclogenesis (TCG) bias to large-scale circulation in global circulation models is challenging. Here, we propose the use of empirical orthogonal functions as an approach to understand model bias of TCG. This approach could be deployed more widely to other basins and models to diagnose the causes of TCG bias.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Environmental Sciences
Mary-Jane M. Bopape, Hipolito Cardoso, Robert S. Plant, Elelwani Phaduli, Hector Chikoore, Thando Ndarana, Lino Khalau, Edward Rakate
Summary: The study shows that scale-aware schemes in tropical cyclone simulations help the model resolve most dynamics and result in higher weather system intensity. However, differences in predicting the path of Idai were found among different parameterization schemes.
Article
Meteorology & Atmospheric Sciences
Hsu-Feng Teng, James M. Done, Ying-Hwa Kuo
Summary: This study analyzes the impacts of tropical cyclones formed in monsoon and easterly environments on the major coastlines of the western North Pacific basin. It finds that monsoon-type TCs predominantly affect southern China, Taiwan, and Vietnam, while easterly-type TCs tend to impact eastern China, southern Japan, and the Philippines.
QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY
(2021)
Article
Meteorology & Atmospheric Sciences
Rajitha Athukorala, Thaileng Thol, Panduka Neluwala, Monica Petri, Sorlaty Sengxeu, Larxoy Lattada, Sengkeo Keomanivong, Viengkham Sithivong
Summary: The study evaluated an ensemble of physics options in simulating rainfall during wet and dry seasons in Lao PDR, finding that different physics options should be chosen based on specific scenarios.
ADVANCES IN METEOROLOGY
(2021)
Article
Engineering, Civil
David Feldmann, Patrick Laux, Andreas Heckl, Manfred Schindler, Harald Kunstmann
Summary: The study aims to determine robust Manning resistance coefficients (n) based on consecutive artificial rainfall experiments on natural hillslopes available in literature. Manning resistance coefficient is particularly important in 2D hydraulic heavy rainfall simulations, as there is a wide range of possible resistance values available leading to significantly different results regarding the accumulation of surface runoff.
JOURNAL OF HYDROLOGY
(2023)
Article
Environmental Studies
Eric Mensah Mortey, Thompson Annor, Joel Arnault, Maman Maarouhi Inoussa, Saidou Madougou, Harald Kunstmann, Emmanuel Kwesi Nyantakyi
Summary: This study uses historical land cover data and standardized climatic indices to explore climate-land interactions in West Africa. The results show that abrupt changes in climatic conditions lead to land cover changes, with conversions of cropland, forest, grassland, and shrubland being the main types affecting the climate.
Article
Computer Science, Information Systems
Moumouni Djibo, Wend Yam Serge Boris Ouedraogo, Ali Doumounia, Serge Roland Sanou, Moumouni Sawadogo, Idrissa Guira, Nicolas Kone, Christian Chwala, Harald Kunstmann, Francois Zougmore
Summary: Since the 1990s, mobile telecommunication networks have become denser worldwide, with a significant portion relying on commercial microwave links (CMLs) for backhaul. By exploiting the attenuation of CML signals caused by rainfall, records of this attenuation can be used for inexpensive precipitation monitoring. To implement this technology, a real-time system has been developed to collect and store CML power levels from Telecel Faso, a mobile operator in Burkina Faso. This system, based on the Simple Network Management Protocol (SNMP), has grown from eight to over 1000 radio links, covering major cities and connecting routes in Burkina Faso.
APPLIED SYSTEM INNOVATION
(2023)
Article
Agronomy
Xuejin Wang, Baoqing Zhang, Zhenyu Zhang, Lei Tian, Harald Kunstmann, Chansheng He
Summary: Understanding the spatiotemporal evolution of droughts is crucial for food security and water allocation. This study proposes an approach to explore the simultaneous spatiotemporal evolution of droughts by constructing the linkage of propagation from meteorological drought to agricultural drought. The results show that 53.75% of meteorological drought events progress further to agricultural droughts, and agricultural droughts have a longer duration than meteorological droughts.
AGRICULTURAL AND FOREST METEOROLOGY
(2023)
Article
Meteorology & Atmospheric Sciences
Windmanagda Sawadogo, Jan Bliefernicht, Benjamin Fersch, Seyni Salack, Samuel Guug, Kehinde O. Ogunjobi, Stefanie Meilinger, Harald Kunstmann
Summary: The study evaluates different shortwave radiation schemes from the Weather Research and Forecasting (WRF) Model option Solar (WRF-Solar) for solar irradiance forecasting in Ghana and the southern part of Burkina Faso. The results show that the RRTMG_AERO_D01 scheme generally outperforms other schemes in simulating global horizontal irradiance under different weather conditions. It is recommended to use the RRTMG_AERO scheme for solar irradiance forecasts in the study area.
JOURNAL OF APPLIED METEOROLOGY AND CLIMATOLOGY
(2023)
Article
Environmental Sciences
Ningpeng Dong, Mingxiang Yang, Jianhui Wei, Joel Arnault, Patrick Laux, Shiqin Xu, Hao Wang, Zhongbo Yu, Harald Kunstmann
Summary: This study proposes a synergistic framework to predict the release, storage, and hydropower production of ungauged reservoirs by combining remotely sensed reservoir operating patterns and model-simulated reservoir inflow within a land surface-hydrologic model. The study shows that remote sensing can improve the parameter estimation and simulations of ungauged reservoirs, but most operation schemes show degraded accuracies under changing inflow regimes. In comparison, the newly extended reservoir operation scheme in this study proves to be more adaptable to flow regime variations.
WATER RESOURCES RESEARCH
(2023)
Article
Meteorology & Atmospheric Sciences
Xuejin Wang, Zhenyu Zhang, Baoqing Zhang, Lei Tian, Jie Tian, Joel Arnault, Harald Kunstmann, Chansheng He
Summary: This study investigates the impact of land use and land cover change on regional atmospheric moisture cycling in the agro-pastoral ecotone of northern China. Results show that evapotranspiration contributes to local and regional precipitation, and surface vegetation change affects the thermodynamic processes and atmospheric responses.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2023)
Article
Meteorology & Atmospheric Sciences
Patrick Olschewski, Patrick Laux, Jianhui Wei, Brian Boeker, Zhan Tian, Laixiang Sun, Harald Kunstmann
Summary: The effectiveness of adaptive measures to address the impacts of climate change depends on accurate climate projections, especially in the increasingly prevalent extreme events. Flooding poses a significant threat to vulnerable coastal urban areas, including major cities like Shanghai and Shenzhen in eastern Asia. Despite improvements in general circulation models (GCMs) and regional climate models (RCMs) for projecting atmospheric changes related to these events, biases still exist. This study evaluates the potential of enhancing regional climate projections for eastern Asia by employing bias adjustment methods, GCM-RCM model runs, and future emission scenarios.
WEATHER AND CLIMATE EXTREMES
(2023)
Article
Agronomy
Zhenyu Zhang, Patrick Laux, Jussi Baade, Joel Arnault, Jianhui Wei, Xuejin Wang, Yukun Liu, Christiane Schmullius, Harald Kunstmann
Summary: Numerical weather and climate prediction models rely on accurate soil data to model land surface processes. However, global soil datasets show wide discrepancies due to uncertainties from soil profiles and maps. This study examines the impact of different global soil datasets on land-atmosphere interactions in southern Africa. The results show that soil texture differences have a significant effect on simulated temperature, soil moisture, surface energy fluxes, and local climatic conditions. The study emphasizes the importance of considering modeling uncertainties from soil data in land surface-atmosphere coupled modeling.
AGRICULTURAL AND FOREST METEOROLOGY
(2023)
Review
Environmental Sciences
Patrick Laux, Elena Weber, David Feldmann, Harald Kunstmann
Summary: This study uses both stationary and non-stationary extreme value analysis (EVA) models to derive design life levels (DLLs) of daily precipitation in the Oberland region of Southern Germany. Different parameter estimation techniques and theoretical distributions are evaluated and compared. The study reveals large methodological uncertainties and no robust tendency towards increased extremes for the end of this century in the study area.
Article
Astronomy & Astrophysics
Nico Blettner, Martin Fencl, Vojtech Bares, Harald Kunstmann, Christian Chwala
Summary: Unlike actual rainfall, the spatial extent of rainfall maps is often constrained by administrative and political boundaries, limiting transboundary exchange of data. However, this study presents the first transboundary rainfall maps generated using commercial microwave link (CML) data sets from Germany and the Czech Republic. By applying quality control algorithms, anomalies in the results are significantly reduced, enabling seamless visualization of rainfall events across the German-Czech border. This highlights the importance of quality control for large-scale CML-based rainfall estimation.
EARTH AND SPACE SCIENCE
(2023)
Article
Environmental Sciences
Joel Arnault, Anthony Musili Mwanthi, Tanja Portele, Lu Li, Thomas Rummler, Benjamin Fersch, Mohammed Abdullahi Hassan, Titike Kassa Bahaga, Zhenyu Zhang, Eric Mensah Mortey, Ifeany Chukwudi Achugbu, Hassane Moutahir, Souleymane Sy, Jianhui Wei, Patrick Laux, Stefan Sobolowski, Harald Kunstmann
Summary: This study investigates the impact of afforestation on regional climate in a heavily farmed region of tropical Africa. The results show that afforestation can decrease soil evaporation and increase plant transpiration, leading to increased sensible heat flux, precipitation, and runoff, thus affecting regional water resources.
FRONTIERS IN CLIMATE
(2023)
Proceedings Paper
Acoustics
Julius Polz, Luca Glawion, Maximilian Graf, Nico Blettner, Zbieta Lasota, Lennart Schmidt, Harald Kunstmann, Christian Chwala
Summary: Accurate detection of signal anomalies in commercial microwave links (CMLs) attenuation time-series is crucial for high quality rainfall estimates. Examples of anomalies include dew/ice on the antenna and multipath propagation. A study analyzing 20 CMLs in Germany found that removing flagged anomalies improved the correlation between CML and radar rainfall estimates, emphasizing the importance of considering expert uncertainty in quality control of environmental sensor data.
2023 IEEE INTERNATIONAL CONFERENCE ON ACOUSTICS, SPEECH, AND SIGNAL PROCESSING WORKSHOPS, ICASSPW
(2023)
Article
Geosciences, Multidisciplinary
Efi Rousi, Andreas H. Fink, Lauren S. Andersen, Florian N. Becker, Goratz Beobide-Arsuaga, Marcus Breil, Giacomo Cozzi, Jens Heinke, Lisa Jach, Deborah Niermann, Dragan Petrovic, Andy Richling, Johannes Riebold, Stella Steidl, Laura Suarez-Gutierrez, Jordis S. Tradowsky, Dim Coumou, Andre Dusterhus, Florian Ellsaesser, Georgios Fragkoulidis, Daniel Gliksman, Doerthe Handorf, Karsten Haustein, Kai Kornhuber, Harald Kunstmann, Joaquim G. Pinto, Kirsten Warrach-Sagi, Elena Xoplaki
Summary: The summer of 2018 experienced simultaneous, widespread, and concurrent heat and drought extremes in northern and central Europe, with significant impacts on agriculture, forests, water supply, and the socio-economic sector. The study provides a comprehensive analysis of the extreme summer in terms of heat and drought, particularly focusing on Germany. The research identifies the atmospheric circulation patterns and climate precursors, as well as the probabilistic attribution of the heatwave to anthropogenic global warming. Future projections indicate a higher frequency and intensity of extreme summers under climate change. Such studies are crucial for adaptation and mitigation strategies.
NATURAL HAZARDS AND EARTH SYSTEM SCIENCES
(2023)
Article
Geosciences, Multidisciplinary
Gerhard Smiatek, Harald Kunstmann
Summary: The pan-African Great Green Wall for the Sahara and the Sahel initiative aims to reverse land degradation through reforestation. However, our investigation found no significant evidence that the GGW-induced changes in precipitation characteristics or positive impacts on forestation activities in the Sahel. Our simulations showed regional-scale changes in precipitation, but they were not statistically significant at the 5% level.
EARTH INTERACTIONS
(2023)