A5059608069- Climate variability and models
- Atmospheric and Environmental Gas Dynamics
- Meteorological Phenomena and Simulations
- Tropical and Extratropical Cyclones Research
- Atmospheric chemistry and aerosols
- Scientific Research and Discoveries
- Stellar, planetary, and galactic studies
- Atmospheric Ozone and Climate
- Advanced Thermodynamics and Statistical Mechanics
- Greenhouse Technology and Climate Control
- Geophysics and Gravity Measurements
- Methane Hydrates and Related Phenomena
- Marine and coastal ecosystems
- Light effects on plants
- Climate Change Policy and Economics
- Astro and Planetary Science
- Milk Quality and Mastitis in Dairy Cows
- Oceanographic and Atmospheric Processes
- Geomagnetism and Paleomagnetism Studies
- Geology and Paleoclimatology Research
- Cyclone Separators and Fluid Dynamics
- Soil erosion and sediment transport
- Atmospheric aerosols and clouds
- History and Developments in Astronomy
- Solar and Space Plasma Dynamics
Laboratoire de Météorologie Dynamique
2018-2021
École Polytechnique
2019-2021
Sorbonne Université
2018-2021
BOKU University
2021
École Normale Supérieure - PSL
2019-2020
Centre National de la Recherche Scientifique
2019-2020
Max Planck Institute for Meteorology
2014-2019
Infektionsmedizinisches Centrum Hamburg
2019
NOAA Geophysical Fluid Dynamics Laboratory
2017
Princeton University
2016-2017
A new release of the Max Planck Institute for Meteorology Earth System Model version 1.2 (MPI-ESM1.2) is presented. The development focused on correcting errors in and improving physical processes representation, as well computational performance, versatility, overall user friendliness. In addition to radiation aerosol parameterizations atmosphere, several relatively large, but partly compensating, coding model's cloud, convection, turbulence were corrected. representation land was refined...
Abstract The Radiative‐Convective Equilibrium Model Intercomparison Project (RCEMIP) is an intercomparison of multiple types numerical models configured in radiative‐convective equilibrium (RCE). RCE idealization the tropical atmosphere that has long been used to study basic questions climate science. Here, we employ investigate role clouds and convective activity play determining cloud feedbacks, sensitivity, state aggregation, climate. RCEMIP unique among intercomparisons its inclusion a...
Water-rich planets such as Earth are expected to become eventually uninhabitable, because liquid water does not remain stable at the surface temperatures increase with solar luminosity over time. Whether a large of atmospheric concentrations greenhouse gases CO$_2$ could also destroy habitability water-rich has remained unclear. We show three-dimensional aqua-planet numerical experiments that CO$_2$-induced forcing readily destabilizes climate forcing. The instability is caused by positive...
Abstract The energy demand for heating and cooling buildings is changing with global warming. Using proxies of climate-driven based on the Degree-Days methodology applied to thirty climate model simulations, we show that, over all continental areas, trends were weak, by less than 10% from 1950 1990, but become stronger 1990 2030, more 10%. With multi-model mean, increasing in are pronounced decreasing heating. changes cooling, however, highly variable depending individual ranging a few...
Abstract The discovery of planets orbiting double stars at close distances has sparked increasing scientific interest in determining whether Earth-analogues can remain habitable such environments and how their atmospheric dynamics is influenced by the rapidly changing insolation. In this work we present results first three-dimensional numerical experiments a water-rich planet star. We find that periodic forcing atmosphere noticeable impact on planet’s climate. Signatures frequencies related...
A major bias in tropical precipitation over the Pacific climate simulations stems from models’ tendency to produce two strong distinct intertropical convergence zones (ITCZs) too often. Several mechanisms have been proposed that may contribute emergence of ITCZs, but current theories cannot fully explain bias. This problem is tackled by investigating how interaction between atmospheric cloud-radiative effects (ACREs) and large-scale circulation influences ITCZ position an general model....
Abstract The tropical zonal‐mean precipitation in climate models is well known to have substantial biases such as an erroneous double intertropical convergence zone the Pacific, but a comprehensive quantification of these currently missing. Therefore, we introduce set nine indicators that fully characterize position and magnitude extrema precipitation. An analysis Coupled Model Intercomparison Project (CMIP) historical Atmospheric (AMIP) simulations reveals large and, especially, both sets...
Abstract The rate of transient warming is determined by a number factors, notably the radiative forcing from increasing CO 2 concentrations and net feedback. Uncertainty in comes both uncertainty each factor warming's sensitivity to factor. An energy balance model used untangle these two components warming, which shown be most sensitive not feedbacks. Additionally, efficacy ocean heat uptake more important than uptake. Three further implications are as follows: (1) highly emissions, (2)...
Low-cloud based emergent constraints have the potential to substantially reduce uncertainty in Earth's equilibrium climate sensitivity, but recent work has shown that previously developed fail latest generation of models, suggesting new approaches are needed. Here, we investigate for regional cloud feedbacks, rather than global-mean feedback. Strong relationships found between monthly and interannual variability tropical clouds, net These combined with observations narrow feedback...
Abstract A one-dimensional radiative–convective equilibrium model is used to investigate the influence of clouds on onset a runaway greenhouse under strong solar forcing. By comparing experiments with clear-sky conditions (clouds are transparent radiation) full-sky radiatively active), authors find that critical irradiance necessary trigger increased from around 1.15–1.20 times present-day total (TSI) Earth S0 for 1.40–1.45S0 conditions. Cloud thickness increases TSI, leading substantially...
We investigate the influence of rotation period ( $${\rm P}_{rot}$$ ) on mean climate an aquaplanet, with a focus role sea-ice albedo. perform aquaplanet simulations atmospheric general circulation model ECHAM6 for various periods from one Earth-day to 365 Earth-days in which case planet is synchronously rotating. The global-mean surface temperature decreases increasing and sea ice expands equatorwards. cooling caused partly by high albedo dayside deep convective clouds over substellar...
Abstract Deep convection can exhibit a large diversity of spatial organizations along the equator. The form organization may affect tropical large-scale motions atmosphere, but observational evidence is currently missing. Here we show using observations that when equator more clustered in zonal direction, rain belt widens meridional and exhibits double-peak structure. About half influence convective clustering on width associated with annual cycle other unforced climate variability....
Convective clustering, the spatial organization of tropical deep convection, can manifest itself in two ways: through a decrease total area covered by convection and/or number convective areas. Much our current understanding clustering comes from simulations idealized radiative equilibrium (RCE) configurations. In these forms tend to covary, and their individual effects on climate are thus hard disentangle. This study shows that aquaplanet with more realistic boundary conditions, such as...
Strong links are seen in observations between convective clustering and several properties of the Intertropical Convergence Zone (ITCZ). These suggest that biases how climate models simulate ITCZ may be related to model or there represent relationship ITCZ. We investigate these issues by analyzing clustering, link 18 models. find variability generally weaker less robust than observations. By contrast, climatological explain a substantial fraction double-ITCZ bias, though they do not width.
The relative contributions of the meridional gradients in insolation and longwave optical depth (caused by water vapor) to equator-to-pole temperature difference, Earth’s climate general, have not been quantified before. As a first step understanding these contributions, this study investigates simulations with an idealized general circulation model which are eliminated individually or jointly, while keeping global means fixed. gradient has larger influence on model’s than depth, but both...