Local Drivers of Marine Heatwaves: A Global Analysis With an Earth System Model

Frontiers in Climate, Год журнала: 2022, Номер 4

Опубликована: Май 3, 2022

Marine heatwaves (MHWs) are periods of extreme warm ocean temperatures that can have devastating impacts on marine organisms and socio-economic systems. Despite recent advances in understanding the underlying processes individual events, a global view local oceanic atmospheric drivers MHWs is currently missing. Here, we use daily-mean output temperature tendency terms from comprehensive fully coupled coarse-resolution Earth system model to quantify main leading onset decline surface different seasons. The subtropics mid-to-high latitudes primarily driven by net heat uptake associated with reduction latent loss all seasons, increased shortwave absorption summer reduced sensible winter, dampened vertical mixing non-local portion K-Profile Parameterization boundary layer scheme (KPP) especially summer. In tropics, lowered diffusion cause warming. subsequent phase, atmosphere due enhanced seasons together high during dominate decrease globally. similar for short long MHWs, but there differences between winter. Different types distinct driver combinations identified within large variability among events. Our analysis contributes better MHW may therefore help improve prediction high-impact heatwaves.

Язык: Английский

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The importance of internal climate variability in climate impact projections

Proceedings of the National Academy of Sciences, Год журнала: 2022, Номер 119(42)

Опубликована: Окт. 10, 2022

Uncertainty in climate projections is driven by three components: scenario uncertainty, intermodel and internal variability. Although socioeconomic impact studies increasingly take into account the first two components, little attention has been paid to role of variability, although underestimating this uncertainty may lead costs change. Using large ensembles from seven coupled general circulation models with a total 414 model runs, we partition classic dose-response relating county-level corn yield, mortality, per-capita gross domestic product temperature continental United States. The partitioning depends on time frame projection, model, geographic region. Internal variability represents more than 50% certain projections, including mortality for early 21st century, its relative influence decreases over time. We recommend due many temperature-driven impacts, early-century midcentury regions high such as Upper Midwest States, impacts nonlinear relationships.

Язык: Английский

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A range of outcomes: the combined effects of internal variability and anthropogenic forcing on regional climate trends over Europe

Nonlinear processes in geophysics, Год журнала: 2023, Номер 30(1), С. 63 - 84

Опубликована: Фев. 15, 2023

Abstract. Disentangling the effects of internal variability and anthropogenic forcing on regional climate trends remains a key challenge with far-reaching implications. Due to its largely unpredictable nature timescales longer than decade, limits accuracy model projections, introduces challenges in attributing past changes, complicates evaluation. Here, we highlight recent advances modeling physical understanding that have led novel insights about these issues. In particular, synthesize new findings from large-ensemble simulations Earth system models, observational large ensembles, dynamical adjustment methodologies, focus European climate.

Язык: Английский

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Extreme heat and drought typical of an end-of-century climate could occur over Europe soon and repeatedly

Communications Earth & Environment, Год журнала: 2023, Номер 4(1)

Опубликована: Ноя. 30, 2023

Abstract Extreme heat and drought typical of an end-of-century climate could soon occur over Europe, repeatedly. Despite the European being potentially prone to multi-year successive extremes due influence North Atlantic variability, it remains unclear how likelihood changes under warming, early they reach levels, this is affected by internal variability. Using Max Planck Institute Grand Ensemble, we find that even moderate levels virtually impossible 20 years ago 1-in-10 likelihoods as 2030s. By 2050–2074, two single or compound extremes, unprecedented date, exceed likelihoods; while Europe-wide 5-year megadroughts become plausible. Whole decades stress start 2040, 2020 for drought, with a warm Atlantic, starting 2030 twice likely.

Язык: Английский

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The New Max Planck Institute Grand Ensemble With CMIP6 Forcing and High‐Frequency Model Output

Journal of Advances in Modeling Earth Systems, Год журнала: 2023, Номер 15(10)

Опубликована: Окт. 1, 2023

Abstract Single‐model initial‐condition large ensembles are powerful tools to quantify the forced response, internal climate variability, and their evolution under global warming. Here, we present CMIP6 version of Max Planck Institute Grand Ensemble (MPI‐GE CMIP6) with currently 30 realizations for historical period five emission scenarios. The power MPI‐GE goes beyond its predecessor ensemble by providing high‐frequency output, full range scenarios including highly policy‐relevant low SSP1‐1.9 SSP1‐2.6, opportunity compare complementary high‐resolution simulations. First, describe CMIP6, evaluate it observations reanalyzes MPI‐GE. Then, demonstrate six application examples how use better understand future extremes, inform about uncertainty in approaching Paris Agreement warming limits, combine artificial intelligence. For instance, allows us show that recently observed Siberian Pacific North American heatwaves would only avoid reaching 1–2 years return periods 2071–2100 scenarios, European precipitation extremes captured simulations, 3‐hourly output projects a decreasing activity storms mid‐latitude oceans. Further, is ideal estimates probabilities crossing limits irreducible introduced sufficiently be used infilling surface temperature

Язык: Английский

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Interpreting extreme climate impacts from large ensemble simulations—are they unseen or unrealistic?

Environmental Research Letters, Год журнала: 2022, Номер 17(4), С. 044052 - 044052

Опубликована: Март 11, 2022

Abstract Large-ensemble climate model simulations can provide deeper understanding of the characteristics and causes extreme events than historical observations, due to their larger sample size. However, adequate evaluation simulated ‘unseen’ that are more those seen in records is complicated by observational uncertainties natural variability. Consequently, conventional correction methods cannot determine whether outside observed variability correct for right physical reasons. Here, we introduce a three-step procedure assess realism based on properties (step 1), statistical features 2), credibility 3). We illustrate these steps 2000 year Amazon monthly flood ensemble global EC-Earth hydrological PCR-GLOBWB. PCR-GLOBWB large-scale catchments like Amazon, have floods far find be statistically explained. For example, there could legitimate discrepancies between observations resulting from infrequent temporal compounding multiple peaks, rarely observations. Physical checks crucial assessing show unseen were generated an unrealistic bias precipitation. conclude high sensitivity method, what driving events. Understanding mechanisms may guide future research uncovering key deficiencies. They also play vital role helping decision makers anticipate impacts detecting plausible drivers.

Язык: Английский

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An open workflow to gain insights about low‐likelihood high‐impact weather events from initialized predictions

Meteorological Applications, Год журнала: 2022, Номер 29(3)

Опубликована: Май 1, 2022

Abstract Low‐likelihood weather events can cause dramatic impacts, especially when they are unprecedented. In 2020, amongst other high‐impact events, UK floods caused more than £300 million damage, prolonged heat over Siberia led to infrastructure failure and permafrost thawing, while wildfires ravaged California. Such rare phenomena cannot be studied well from historical records or reanalysis data. One way improve our awareness is exploit ensemble prediction systems, which represent large samples of simulated events. This ‘UNSEEN’ method has been successfully applied in several scientific studies, but uptake hindered by data processing requirements, uncertainty regarding the credibility simulations. Here, we provide a protocol apply ensure UNSEEN for studying low‐likelihood globally, including an open workflow based on Copernicus Climate Change Services (C3S) seasonal predictions. Demonstrating using European Centre Medium‐Range Weather Forecasts (ECMWF) SEAS5, find that 2020 March–May Siberian heatwave was predicted one members; record‐shattering August California‐Mexico temperatures were part strong increasing trend. However, each case studies exposes challenges with respect sensitivity outcomes user decisions. We conclude new insights about decisions transparent, sensitivities acknowledged. Anticipating plausible extreme uncovering unforeseen hazards under changing climate warrants further research at science‐policy interface manage high impacts.

Язык: Английский

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Projected amplification of summer marine heatwaves in a warming Northeast Pacific Ocean

Communications Earth & Environment, Год журнала: 2024, Номер 5(1)

Опубликована: Янв. 26, 2024

Abstract Marine heatwaves are expected to become more frequent, intense, and longer-lasting in a warming world. However, it remains unclear whether feedback processes could amplify or dampen extreme ocean temperatures. Here we impose the observed atmospheric flow coupled climate simulations determine how record-breaking 2019 Northeast Pacific marine heatwave would have unfolded preindustrial times, unravel +4 °C warmer world compared present-day conditions. We find that air-sea interactions, involving reductions clouds mixed-layer depth air advection from fast-warming subpolar regions, modulate rates within heatwave. In climate, global oceans +1.9 than present levels, regional mean can reach +2.3–2.7 ± 0.25 °C. Our identified projected further intensity spatial extent of analogous summer beyond those thresholds, with reaching +2.9 0.15 above levels. Such an event-specific amplification place even greater stress on ecosystems fisheries.

Язык: Английский

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Rising risks of hydroclimatic swings: A large ensemble study of dry and wet spell transitions in North America

Global and Planetary Change, Год журнала: 2024, Номер 238, С. 104476 - 104476

Опубликована: Май 20, 2024

Hydroclimatic swings between dry and wet spells are increasing globally, raising concerns due to their severe impacts on society, agriculture, infrastructure systems, water resource management. These extremes projected changes traditionally assessed in isolation, which can underestimate associated risks future resilience adaptation plans. This study investigates climate change projections of such lagged compound across North America using a single model initial-condition large ensemble (SMILE). Three dry-wet spell indices merged into an integrated indicator provide comprehensive perspective changing risks. We apply pooling approach the Canadian Regional Climate Model version 4 Large Ensemble (CanRCM4-LE) enhance sample size for index estimation. Results suggest that hydroclimatic expected become more frequent intensified warmer climate. Trends spatial fraction aggregation during transitions indicate management challenges. Hot spots with higher frequency, as Northern Central America, southern part Eastern Western including Mexico state California, overlap larger extent transitions. The seasonal analysis characteristics indicates winter may wetter summer drier at warming levels, potentially intensifying extremes. Clustered lead environmental, hydrological, socio-economic consequences, necessitating appropriate mitigation measures.

Язык: Английский

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Variability in flood frequency in Sub-Saharan Africa: The role of large-scale climate modes of variability and their future impacts

Journal of Hydrology, Год журнала: 2024, Номер 640, С. 131679 - 131679

Опубликована: Июль 14, 2024

Sub-Saharan Africa (SSA) is strongly affected by flood hazards, endangering human lives and economic stability. However, the role of internal climate modes variability in driving fluctuations SSA occurrence remains poorly documented understood. To address this gap, we quantify relative combined contribution large-scale drivers to seasonal regional using a new 65-year daily streamflow dataset, sea-surface temperatures derived from observations, 12 Single Model Initial-condition Large Ensembles (SMILEs) Coupled Intercomparison Project Phases 5 6. We find significant relationships between floods across SSA, with climatic accounting for 30–90 % floods. Notably, western, central, summer-rain region southern display stronger teleconnections comparison East winter-rain South Africa, where circulation patterns activities may play more important role. In eastern are mainly influenced Pacific Indian Oceans, while western central Atlantic Ocean Mediterranean Sea larger also that number projected fluctuate ± 10–50 during 21st century response different sequences key variability. note contributions future risks generally consistent all SMILEs. Our findings thus provide valuable information long-term disaster risk reduction management.

Язык: Английский

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