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

Frontiers in Climate, Journal Year: 2022, Volume and Issue: 4

Published: May 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.

Language: Английский

---

The importance of internal climate variability in climate impact projections

Proceedings of the National Academy of Sciences, Journal Year: 2022, Volume and Issue: 119(42)

Published: Oct. 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.

Language: Английский

---

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

Nonlinear processes in geophysics, Journal Year: 2023, Volume and Issue: 30(1), P. 63 - 84

Published: Feb. 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.

Language: Английский

---

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

Communications Earth & Environment, Journal Year: 2023, Volume and Issue: 4(1)

Published: Nov. 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.

Language: Английский

---

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

Journal of Advances in Modeling Earth Systems, Journal Year: 2023, Volume and Issue: 15(10)

Published: Oct. 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

Language: Английский

---

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

Environmental Research Letters, Journal Year: 2022, Volume and Issue: 17(4), P. 044052 - 044052

Published: March 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.

Language: Английский

---

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

Meteorological Applications, Journal Year: 2022, Volume and Issue: 29(3)

Published: May 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.

Language: Английский

---

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

Communications Earth & Environment, Journal Year: 2024, Volume and Issue: 5(1)

Published: Jan. 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.

Language: Английский

---

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

Journal of Hydrology, Journal Year: 2024, Volume and Issue: 640, P. 131679 - 131679

Published: July 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.

Language: Английский

---

Spatiotemporal Variability of Current and Future Sub‐Daily Rainfall in Japan Using State‐Of‐The‐Art High‐Quality Data Sets

Water Resources Research, Journal Year: 2023, Volume and Issue: 59(4)

Published: April 1, 2023

Abstract Using potentially best available rainfall data sets for the entire country of Japan (spatial scales 1‐ and 20‐km), we analyze 1–24 hr city‐scale (1–400 km 2 ) extreme rainfalls both current (2006–2020) future periods (2081–2109) at 1.5 K global warming scenario, complementing previous work that focuses on either coarse spatial temporal or other scenarios (e.g., RCP scenarios). A peak‐over‐threshold (POT)‐based approach is applied to compute areal reduction factor (ARF) subsequently establishing intensity‐duration‐area‐frequency (IDAF) curves. Our results reveal ARF values generally decrease with increasing area size increase longer duration are affected by multiple underlying physical phenomena. Moreover, find a greater in intensities shorter durations higher return periods, ranging from 9.4% (1‐hr) 6.2% (24‐hr), averaged all 8.3% (25‐year) 7.3% (2‐year), durations. Spatially, projected 8.9% northern (albeit less intense intensity period), which than rest (6.8%), underscoring need focus more infrastructure designs Japan. The IDAF curves further display an frequency events city‐scale, example, 25‐year 2006–2020 would likely be 5‐10‐year 2081–2109. state‐of‐the‐art implementable can utilized policymaking reduce warming‐induced risks beyond.

Language: Английский

---