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5. How Do the Tropics Precipitate? Daily Variations in Precipitation and Cloud Distribution.

Author

SEGURA, Hans and HOHENEGGER, Cathy

Subjects
*PRECIPITATION variability, *PROBABILITY density function, *CONVECTIVE clouds, *CLOUDINESS, *RATE setting
Abstract

What controls the variability of daily precipitation averaged over the tropics? Are these the most numerous precipitation rates or the most intense ones? And do they relate to a specific cloud type? This work addresses these questions using precipitation from the one-year simulation of the global-coupled storm-resolving ICOsahedral Non-hydrostatic model run in its Sapphire configuration (ICON-Sapphire) and observations. Moreover, we develop a framework to analyze the precipitation variability based on the area covered by and the mean intensity of different groups of precipitation rates. Our framework shows that 60 % of the precipitation variability is explained by precipitation rates between 20 mm d-1 and 70 mm d-1, but those precipitation rates only explain 46 % of the mean precipitation in the tropics. The decomposition of the precipitation variability into the area fraction and mean intensity of a set of precipitation rates shows that this variability is explained by changes in the area fraction covered by precipitation rates between 20 mm d-1 and 70 mm d-1, not by changes in the mean intensity. These changes in the area fraction result from changes in the area covered by congestus clouds, not by cumulonimbus or shallow clouds, even though congesti and cumulonimbi contribute equally to the mean tropical precipitation. Overall, ICON-Sapphire reproduces the probability density function of precipitation rates and the control of specific precipitation rates on the tropical mean precipitation and variability compared to observations. [ABSTRACT FROM AUTHOR]

Published
2024
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11. ICON-Sapphire: simulating the components of the Earth system and their interactions at kilometer and subkilometer scales

Author

Hohenegger, Cathy, Korn, Peter, Linardakis, Leonidas, Redler, René, Schnur, Reiner, Adamidis, Panagiotis, Bao, Jiawei, Bastin, Swantje, Behravesh, Milad, Bergemann, Martin, Biercamp, Joachim, Bockelmann, Hendryk, Brokopf, Renate, Brüggemann, Nils, Casaroli, Lucas, Chegini, Fatemeh, Datseris, George, Esch, Monika, Geet, George, Giorgetta, Marco, Gutjahr, Oliver, Haak, Helmuth, Hanke, Moritz, Ilyina, Tatiana, Jahns, Thomas, Jungclaus, Johann, Kern, Marcel, Klocke, Daniel, Kluft, Lukas, Kölling, Tobias, Kornblueh, Luis, Kosukhin, Sergey, Kroll, Clarissa, Lee, Junhong, Mauritsen, Thorsten, Mehlmann, Carolin, Mieslinger, Theresa, Naumann, Ann Kristin, Paccini, Laura, Peinado, Angel, Praturi, Divya Sri, Putrasahan, Dian, Rast, Sebastian, Riddick, Thomas, Roeber, Niklas, Schmidt, Hauke, Schulzweida, Uwe, Schütte, Florian, Segura, Hans, Shevchenko, Radomyra, Singh, Vikram, Specht, Mia, Stephan, Claudia Christine, von Storch, Jin-Song, Vogel, Raphaela, Wengel, Christian, Winkler, Marius, Ziemen, Florian, Marotzke, Jochem, and Stevens, Bjorn

Subjects
Ocean, Earth System Modeling, Tropics, General Medicine, Eddie Resolving, ICON-Saphire Model
Abstract

State-of-the-art Earth system models typically employ grid spacings of O(100 km), which is too coarse to explicitly resolve main drivers of the flow of energy and matter across the Earth system. In this paper, we present the new ICON-Sapphire model configuration, which targets a representation of the components of the Earth system and their interactions with a grid spacing of 10 km and finer. Through the use of selected simulation examples, we demonstrate that ICON-Sapphire can (i) be run coupled globally on seasonal timescales with a grid spacing of 5 km, on monthly timescales with a grid spacing of 2.5 km, and on daily timescales with a grid spacing of 1.25 km; (ii) resolve large eddies in the atmosphere using hectometer grid spacings on limited-area domains in atmosphere-only simulations; (iii) resolve submesoscale ocean eddies by using a global uniform grid of 1.25 km or a telescoping grid with the finest grid spacing at 530 m, the latter coupled to a uniform atmosphere; and (iv) simulate biogeochemistry in an ocean-only simulation integrated for 4 years at 10 km. Comparison of basic features of the climate system to observations reveals no obvious pitfalls, even though some observed aspects remain difficult to capture. The throughput of the coupled 5 km global simulation is 126 simulated days per day employing 21 % of the latest machine of the German Climate Computing Center. Extrapolating from these results, multi-decadal global simulations including interactive carbon are now possible, and short global simulations resolving large eddies in the atmosphere and submesoscale eddies in the ocean are within reach.

Published
2023
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14. ICON-Sapphire: simulating the components of the Earth System and their interactions at kilometer and subkilometer scales

Author

Hohenegger, Cathy, primary, Korn, Peter, additional, Linardakis, Leonidas, additional, Redler, René, additional, Schnur, Reiner, additional, Adamidis, Panagiotis, additional, Bao, Jiawei, additional, Bastin, Swantje, additional, Behravesh, Milad, additional, Bergemann, Martin, additional, Biercamp, Joachim, additional, Bockelmann, Hendryk, additional, Brokopf, Renate, additional, Brüggemann, Nils, additional, Casaroli, Lucas, additional, Chegini, Fatemeh, additional, Datseris, George, additional, Esch, Monika, additional, George, Geet, additional, Giorgetta, Marco, additional, Gutjahr, Oliver, additional, Haak, Helmuth, additional, Hanke, Moritz, additional, Ilyina, Tatiana, additional, Jahns, Thomas, additional, Jungclaus, Johann, additional, Kern, Marcel, additional, Klocke, Daniel, additional, Kluft, Lukas, additional, Kölling, Tobias, additional, Kornblueh, Luis, additional, Kosukhin, Sergey, additional, Kroll, Clarissa, additional, Lee, Junhong, additional, Mauritsen, Thorsten, additional, Mehlmann, Carolin, additional, Mieslinger, Theresa, additional, Naumann, Ann Kristin, additional, Paccini, Laura, additional, Peinado, Angel, additional, Praturi, Divya Sri, additional, Putrasahan, Dian, additional, Rast, Sebastian, additional, Riddick, Thomas, additional, Roeber, Niklas, additional, Schmidt, Hauke, additional, Schulzweida, Uwe, additional, Schütte, Florian, additional, Segura, Hans, additional, Shevchenko, Radomyra, additional, Singh, Vikram, additional, Specht, Mia, additional, Stephan, Claudia Christine, additional, von Storch, Jin-Song, additional, Vogel, Raphaela, additional, Wengel, Christian, additional, Winkler, Marius, additional, Ziemen, Florian, additional, Marotzke, Jochem, additional, and Stevens, Bjorn, additional

Published
2022
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17. Deforestation impacts on Amazon-Andes hydroclimatic connectivity

Author

Sierra, Juan Pablo, primary, Junquas, Clementine, additional, Espinoza, Jhan Carlo, additional, Segura, Hans, additional, Condom, Thomas, additional, Andrade, Marcos, additional, Molina-Carpio, Jorge, additional, Ticona, Laura, additional, Mardoñez, Valeria, additional, Blacutt, Luis, additional, Polcher, Jan, additional, Rabatel, Antoine, additional, and Sicart, Jean Emmanuel, additional

Published
2021
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23. A regional view of the linkages between hydro‐climatic changes and deforestation in the Southern Amazon.

Author

Wongchuig, Sly, Espinoza, Jhan Carlo, Condom, Thomas, Segura, Hans, Ronchail, Josyane, Arias, Paola A., Junquas, Clementine, Rabatel, Antoine, and Lebel, Thierry

Subjects
WALKER circulation, LAND cover, DEFORESTATION, CLIMATE change, EVAPOTRANSPIRATION, LAND use
Abstract

In the last four decades, the Southern Amazon (south of 8°S) has shown changes in the spatial and temporal patterns of its hydro‐climatic components, leading to drier conditions. Due to climate and land‐use changes, this region is considered as a zone under biophysical transition processes. Previous studies have documented a complex interaction between climate and deforestation either on a large‐scale or based on limited in situ data, typically covering the Brazilian Amazon. In this study, we analyse the relationships between hydro‐climate, the surface water‐energy partitioning and an index of regional forest cover change for the period 1981–2018. Additionally, we discretized three regions covering the Bolivian Amazon and the southern portions of the Peruvian and Brazilian Amazon due to their differences in the evolution of land use. In the Bolivian region, a high ratio of forest cover change, exceeding 40–50%, is related to a significant tendency to become water‐limited. This change is associated with decreased rainfall, increased potential evapotranspiration and decreased actual evapotranspiration. Regardless of the region analysed, those that are characterized by a high ratio of forest cover change (>40–50%) show growing imbalance between increasing potential and decreasing actual evapotranspiration. However, in the Peruvian and Brazilian regions, hydro‐climatic conditions remain energy‐limited due to minor rainfall changes. The observed differences in surface water‐energy partitioning behaviour evidence a complex dependence of both sub‐regional (i.e., land cover changes) and large‐scale (i.e., strengthening of the Walker and Hadley circulations) conditions. Our findings indicate a clear link between hydro‐climatic changes and deforestation, providing a new perspective on their spatial variability on a sub‐regional scale. [ABSTRACT FROM AUTHOR]

Published
2022
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27. Intra-seasonal rainfall variability in the Amazon basin related to large-scale circulation patterns: a focus on western Amazon-Andes transition region

Author

Paccini, Laura, Espinoza, Jhan Carlo, Ronchail, Josyane, Segura, Hans, Instituto Geofísico del Perú (IGP), Océan et variabilité du climat (VARCLIM), Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN), Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)-Institut de Recherche pour le Développement (IRD)-Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université de Paris (UP)-Institut de Recherche pour le Développement (IRD)-Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU), Université Paris Diderot - Paris 7 (UPD7), Institut des Géosciences de l’Environnement (IGE), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut de Recherche pour le Développement (IRD)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019]), National Innovation Program for Competitiveness and Productivity (PNICP) of Peru through the contract N°397-PNICP-PIAP-2014, HYBAM, Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité)-Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut Pierre-Simon-Laplace (IPSL (FR_636)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-École polytechnique (X)-Centre National d'Études Spatiales [Toulouse] (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Université Paris Cité (UPCité), and Institut de Recherche pour le Développement (IRD)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP )-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Grenoble Alpes [2016-2019] (UGA [2016-2019])

Subjects
[PHYS.PHYS.PHYS-GEO-PH]Physics [physics]/Physics [physics]/Geophysics [physics.geo-ph]
Abstract

This study aims to relate the intra-seasonal rainfall variability over the Amazon basin to atmospheric circulation patterns (CPs), with particular attention to extreme rainfall events in the Amazon–Andes region. The CPs summarize the intra-seasonal variability of atmospheric circulation and are defined using daily low-level winds from the ERA-Interim (1.5° × 1.5°) reanalysis for the 1979–2014 period. Furthermore, observational data of precipitation and high-resolution TRMM 3B42 (∼25 km), 2A25 PR (∼5 km) and CHIRPS (∼5 km) data products are related to the CPs throughout the Amazon basin. Nine CPs are determined using a hybrid method that combines a neural network technique (self-organizing maps, SOM) and hierarchical ascendant classification. The CPs are characterized by a specific cycle with alternative transitions and a duration of 14 days on average. This configuration initially results in northerly winds to southerly winds towards the northern or eastern Amazon basin. The related rainfall suggests that it is driven mainly by CP dynamics. In addition, we demonstrate a good agreement amongst the four rainfall data sets: observed precipitation, TRMM 3B42, TRMM 2A25 PR and CHIRPS. Furthermore, special attention is given to the Amazon–Andes transition region. Over this region, two particular CPs (CP4 and CP5) are identified as the key contributors of maximum and minimum daily rainfall, respectively. Thus, during the dry season, 40.8% (11.4%) of the CP5 (CP4) days demonstrate rainfall of less than 1 mm day−1, while during the wet season, 6.2% (14.6%) of the CP5 (CP4) days show rainfall amounts higher than the seasonal 90th percentile (10.4 mm day−1). This study provides additional information concerning the intra-seasonal circulation variability in Amazonia and demonstrates the value of using remote sensing precipitation data in this region as a tool for forecast in areas lacking observable information.

Published
2018
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29. Reconstrucción de la monzón Sud Americana durante los últimos 10 mil anos y sus efectos en la precipitación del Nordeste de los Andes por medio de registros isotópicos de espeleotemas

Author

Bustamante, Maria Gracia, Cruz, Francisco Da, Vuille, Mathias, Apaéstegui, James, Strikis, Nicolas, G. Panizo, F. Novello, M. Deininger, Sifeddine, Abdel, Cheng, Hai, Moquet, Jean Sébastien, Guyot, Jean Loup, Santos, Roberto, Segura, Hans, and R. Edwards

Published
2016
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33. Tratamiento inmunosupresor combinado en la nefritis lúpica. Reporte de un caso

Author

García Segura, Hans, Figueroa Palomino, Washington, García Segura, Hans, and Figueroa Palomino, Washington

Abstract

El tratamiento de la glomerulonefritis mesangiocapilar, una de las afectaciones más severas de la nefropatía lúpica, se basa en la combinación de esteroides e inmunosupresores. Los “bolos” de metilprednisolona junto a ciclofosfamida intravenosa, se han utilizado para la inducción de la remisión de la enfermedad con resultados eficaces, empleándose otros tipos de agentes en los casos refractarios a esta terapia. El presente caso trata de un paciente masculino 29 años de edad, con antecedentes patológicos personales de asma bronquial, antecedentes patológicos familiares: abuelo fallecido por lupus eritematoso sistémico (LES). Evolución clínica de 5 meses, con fatiga, caída del cabello, fiebre intermitente; tres semanas antes de su admisión presenta edema de miembros inferiores progresivo, oliguria, siendo ingresado por síndrome nefrótico. El laboratorio evidenció al menos cuatro criterios para LES, practicándose biopsia renal, que reveló una glomerulonefritis mesangioendotelial, clase IV, según la OMS estableciéndose su diagnóstico y tratamiento con corticoides e inicio con pulsos mensuales de ciclofosfamida debido a la severidad del cuadro, con mejoría parcial del mismo.

Published
2009

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