A5064167911- Climate variability and models
- Meteorological Phenomena and Simulations
- Oceanographic and Atmospheric Processes
- Atmospheric and Environmental Gas Dynamics
- Marine and coastal ecosystems
- Geology and Paleoclimatology Research
- Plant Water Relations and Carbon Dynamics
- Hydrological Forecasting Using AI
- Arctic and Antarctic ice dynamics
- Geophysics and Gravity Measurements
- Climate Change Policy and Economics
- Tropical and Extratropical Cyclones Research
- Hydrology and Drought Analysis
- Climate change impacts on agriculture
- Complex Systems and Time Series Analysis
- Agricultural risk and resilience
- Species Distribution and Climate Change
- Ecosystem dynamics and resilience
- Hydrology and Watershed Management Studies
- Climate Change Communication and Perception
- Ionosphere and magnetosphere dynamics
- Air Quality Monitoring and Forecasting
- Arctic and Russian Policy Studies
- Cryospheric studies and observations
- Science and Climate Studies
Universität Hamburg
2018-2025
Hamburg Institut (Germany)
2024
Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques
2019-2023
École Normale Supérieure - PSL
2021-2023
Laboratoire de Météorologie Dynamique
2021-2023
Institut Pierre-Simon Laplace
2019-2022
Sorbonne Université
2019-2022
Institut de Recherche pour le Développement
2019-2022
Centre National de la Recherche Scientifique
2019-2022
Environnements et Paléoenvironnements Océaniques et Continentaux
2021
Abstract Due to its wide‐ranging impacts, predicting decadal variations of sea surface temperature (SST) in the subpolar North Atlantic remains a key goal climate science. Here, we compare representation observed SST since 1960 initialized and uninitialized historical simulations from 5th 6th phases Coupled Model Intercomparison Project (CMIP5/6). Initialized hindcasts CMIP6 explain 88% variance post‐1980 gyre at lead years 5–7 (77% simulations) compared 42% (8%) CMIP5, indicating more...
Abstract CMIP5 models have been shown to exhibit rapid cooling events in their projections of the North Atlantic subpolar gyre. Here, we analyze CMIP6 archive, searching for such new generation models. Four out 35 instabilities. The climatic impacts these are large on decadal timescales, with a substantial effect surface temperature over Europe, precipitation pattern tropics—most notably Sahel and Amazon regions—and possible impact mean atmospheric circulation. mechanisms leading related...
Abstract. We have created a performance-based assessment of CMIP6 models for Europe that can be used to inform the sub-selection this region. Our covers criteria indicative ability individual capture range large-scale processes are important representation present-day European climate. use study provide examples how may applied multi-model ensemble (a) filter performance against these climatological and processed-based (b) create smaller subset based on also maintains model diversity...
The north Atlantic subpolar gyre (SPG) has been widely implicated as the source of large-scale changes in marine environment. However, inconsistencies between indices SPG-strength have raised questions about active role and size play determining water properties eastern North (ENA). Here, by analyzing various SPG derived from observations a global coupled model, we show that choice index dictates interpretation strength-salinity relationship ENA. Variability geostrophic currents observed...
An analysis of a three-member ensemble initialized coupled simulations with the MPI-ESM-LR covering period 1901–2010 shows that Atlantic northward ocean heat transport (OHT) at 50°N influences surface temperature variability in North region for several years. Three to ten years after strong OHT phases 50°N, characteristic pattern sea (SST) anomalies emerges: warm are found and cold emerge Gulf Stream region. This originates from persistent upper-ocean content originate southward-propagating...
Observations facilitate model evaluation and provide constraints that are relevant to future predictions projections. Constraints for uninitialized projections generally based on performance in simulating climatology climate change. For initialized predictions, skill scores over the hindcast period insight into relative of models, value initialization as compared Predictions combined can, principle, seamless decadal multi-decadal information. that, though, role observations estimates needs...
Abstract The German Bight coastline is regularly affected by storm surges driven extratropical cyclones. Decadal‐scale predictions of local would foster coastal protection and decision making in areas. We examine the prediction skill Max‐Planck‐Institute Earth System Model (MPI‐ESM) decadal system for three different surge metrics at Cuxhaven (Germany), Esbjerg (Denmark), Delfzijl (The Netherlands). To avoid dynamical downscaling from coarse model output to heights, we use machine learning...
The occurrence of climate extremes is influenced by forcing as well internal variability: variability may temporarily obscure or enhance the forced signal in extremes. role versus noise plays an important role, for instance analysis emergence. extreme indices from Expert Team on Climate Change Detection and Indices (ETCCDI) are routinely used to assess impacts change extremes, but such analyses often ignored. We present a comprehensive catalogue importance 27 ETCCDI inform guide impact...
We use causal effect networks to assess the influence of spring North Atlantic sea surface temperatures (NA-SSTs) on summer East (EA) pattern predictability during 1908–2008. In ERA-20C reanalysis, a robust link is identified for 1958–2008, where meridional SST gradient causes 0.2 standard deviation change in EA. Additionally, index has an estimated negative (~−0.2) 2m air over northwestern Europe. However, both links are absent when analysing full period and...
Future projections suggest that compound heat and drought in Europe will occur more frequently under increasing global warming. Year-to-year variability driven by atmospheric circulation patterns decadal phenomena like the Atlantic Multidecadal Variability (AMV) temporarily dampens or amplifies these changes. As such, frequency intensity of events can be affected anthropogenic natural drivers.Disentangling contributions is essential for understanding current reliability future projections,...
Spring in particular can carry impact-relevant extreme events over Europe, such as late frost or early summer heat. However, the dominating mechanisms and drivers of temperature extremes European springtime are currently not well understood. Across all seasons, one mechanism relevant for Europe is atmospheric blocking. Unlike winter, where blocking predominantly related to cold spells, summer, warm spring a transition period during which both spells might be connected blockings.While this...
Summer heat waves pose health threats to the general population, in particular, vulnerable groups. The skill for seasonal prediction of such has recently advanced. Yet, whether forecast information on this time scale, a scale at which individual preparedness could still be improved, might taken up by has—so far—not been investigated. Here, we present results from large-scale online experiment with population sample Germany (N = 4,251) test how households respond risk...
Abstract We use a decadal prediction system with the Coupled Model Intercomparison Project Phase 6 version of coupled Max Planck Institute Earth System to predict probability occurrence for extremely warm summers in Northern Hemisphere. An assimilation run shows robust response summer temperature extremes northern Europe and northeast Asia North Atlantic sea surface via circumglobal Rossby wavetrain. When is warm, occur 20 % 24 Asia, respectively. In cold phase, these probabilities are 0 8 ....
Where water meets German land, strong winds often push towards the causing high water. Knowing if these high-water days will happen more or less in next few years would help people to be ready for them. The ways we already use know about what come don't understand small enough areas To make this better, computer learning couple highs and lows air low at three places where land: Cuxhaven, Esbjerg, Delfzijl. Our can then turn knowing how change ten into one place years. We check good works...
Climate extremes have increased in frequency and scope recently, this development is projected to continue under ever worsening anthropogenic climate change. Media coverage of extreme weather events plays an important role promoting climate-friendly attitudes, the perception science willingness take collective action for mitigation change adaptation extremes. While Earth System model simulations are becoming more accurate, increasing doubts about results existence recently been observed...
Abstract We demonstrate in this paper that conventional time‐averaged decadal hindcast skill estimates can overestimate or underestimate the credibility of an individual climate forecast. show a long period be higher lower than its subperiods. Instead using measures, we propose to use physical state system at beginning forecast judge credibility. analyze hindcasts North Atlantic sea surface temperature (SST) initialized prediction based on MPI‐ESM‐LR for 1901–2010. Subpolar Ocean heat...
Abstract This study presents an approach to provide seamless climate information by concatenating decadal predictions and projections in time. Results for near‐surface air temperature over 29 regions indicate that such has potential meaningful but can also introduce significant inconsistencies. Inconsistencies are often most pronounced relatively extreme quantiles of the CMIP6 multi‐model ensemble distribution, whereas they generally smaller mostly insignificant close median. The affected...
Abstract We investigate how ocean‐driven multidecadal sea surface temperature (SST) variations force the atmosphere to jointly set pace of Atlantic variability (AMV). generate periodic low‐frequency Meridional Overturning Circulation oscillations by implementing time‐dependent deep‐ocean‐density restoring in MPI‐ESM1.2 explicitly identify driven without any perturbation at ocean‐atmosphere interface. show a coupled experiment that ocean heat convergence positive SST anomalies, turbulent...
Abstract We assess the capability of decadal prediction simulations from Coupled Model Intercomparison Project phase 6 (CMIP6) archive to predict European summer temperature during period 1970–2014. Using a multi-model ensemble average, we show that Southern (SEU) temperatures are highly predictable for up ten years in CMIP6. Much this predictive skill, is related externally forced response: historical explain about 90% observed SEU variance. Prediction skill unforced signal low: initialized...
Abstract We identify subdecadal variations in European summer temperatures coupled and uncoupled century‐long reanalyses. Spectral analyses reveal significant peaks at 5–10 years the midtwentieth century. The show substantial amplitudes of ~1–1.5 °C, associated with extremely warm summers during their positive phases. use forced ocean model experiments that temperature are North Atlantic climate system. A winter NAO‐like forcing is changes circulation mass heat convergence occurring 1–2...
Abstract Interconnections between ocean basins are recognized as an important driver of climate variability. Recent modeling evidence suggests that the North Atlantic can respond to persistent warming tropical Indian Ocean sea surface temperature (SST) relative rest tropics ( rTIO ). Here, we use observational data demonstrate multi-decadal changes in pantropical gradients lead variations SST-based proxy Meridional Overturning Circulation AMOC The largest contribution this gradient-...
We combine a machine learning method and ensemble climate predictions to investigate windows of opportunity for seasonal predictability European summer associated with the North Atlantic jet stream. particularly focus on impact spring sea surface temperatures (SST) four dominant atmospheric teleconnections stream: Oscillation (NAO) in positive negative phases, Ridge (At. Ridge), Low Low). go beyond standard forecast practices by not only identifying these their SST precursors but making use...
Abstract Slowly varying large-scale ocean circulation can provide climate predictability on decadal time scales. It has been hypothesized that the North Atlantic subpolar gyre (SPG) exerts substantial influence predictability. However, a clear identification of downstream impact SPG variations is still lacking. Using MPI-ESM-LR1.2 prediction system, we show along water pathway, dynamical link to causes salinity be considerably better predicted than temperature. By modulating slow northward...