Early warning signal for a tipping point suggested by a millennial Atlantic Multidecadal Variability reconstruction

Nature Communications, Год журнала: 2022, Номер 13(1)

Опубликована: Сен. 2, 2022

Atlantic multidecadal variability is a coherent mode of natural climate occurring in the North Ocean, with strong impacts on human societies and ecosystems worldwide. However, its periodicity drivers are widely debated due to short temporal extent instrumental observations competing effects both internal external factors acting surface temperature variability. Here, we use paleoclimate database an advanced statistical framework generate, evaluate, compare 312 reconstructions over past millennium, based different indices regression methods. From this process, best reconstruction obtained random forest method, robustness checked using model outputs independent oceanic data. This shows that memory variations have strongly increased recently-a potential early warning signal for approach tipping point.

Язык: Английский

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Attribution of multi-annual to decadal changes in the climate system: The Large Ensemble Single Forcing Model Intercomparison Project (LESFMIP)

Frontiers in Climate, Год журнала: 2022, Номер 4

Опубликована: Сен. 16, 2022

Multi-annual to decadal changes in climate are accompanied by extreme events that cause major impacts on society and severe challenges for adaptation. Early warnings of such now potentially possible through operational predictions. However, improved understanding the causes regional these timescales is needed both attribute recent gain further confidence forecasts. Here we document Large Ensemble Single Forcing Model Intercomparison Project will address this need coordinated model experiments enabling different external drivers be isolated. We highlight account errors propose an attribution approach exploits differences between models diagnose real-world situation overcomes potential atmospheric circulation changes. The analysis proposed here provide substantial improvements our ability understand near-term support World Climate Research Program Lighthouse Activity Explaining Predicting Earth System Change.

Язык: Английский

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Emerging unprecedented lake ice loss in climate change projections

Nature Communications, Год журнала: 2022, Номер 13(1)

Опубликована: Окт. 2, 2022

Abstract Seasonal ice in lakes plays an important role for local communities and lake ecosystems. Here we use Large Ensemble simulations conducted with the Community Earth System Model version 2, which includes a simulator, to quantify response of greenhouse warming determine emergence patterns anthropogenic loss. Our model show that average duration coverage maximum thickness are projected decrease over next 80 years by 38 days 0.23 m, respectively. In Canadian Arctic, loss is accelerated cold-season polar amplification. Lake on Tibetan Plateau decreases rapidly due combination strong insolation forcing ice-albedo feedbacks. Comparing signal natural variability represented Ensemble, find ecosystems these regions may be exposed no-analogue within 4-5 decades.

Язык: Английский

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An updated assessment of past and future warming over France based on a regional observational constraint

Earth System Dynamics, Год журнала: 2022, Номер 13(4), С. 1397 - 1415

Опубликована: Окт. 4, 2022

Abstract. Building on CMIP6 climate simulations, updated global and regional observations, recently introduced statistical methods, we provide an assessment of past future warming over France. Following the IPCC AR6 recent global-scale studies, combine model results with observations to constrain change at scale. Over mainland France, forced in 2020 respect 1900–1930 is assessed be 1.66 [1.41 1.90] ∘C, i.e., upper range estimates, almost entirely human-induced. A refined view seasonality this provided through daily normals. Projected response intermediate emission scenario 3.8 ∘C (2.9 4.8 ∘C) 2100 rises up 6.7 [5.2 8.2] a very high scenario, substantially higher than previous ensembles simulations. Winter summer are expected about 15 % lower 30 annual mean warming, respectively, for all scenarios time periods. This work highlights importance combining various lines evidence, including observed data, deliver most reliable information. can feed adaptation planning activities provides additional rationale urgent action. Code made available facilitate replication other areas or political entities.

Язык: Английский

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Global Evaluation of Runoff Simulation From Climate, Hydrological and Land Surface Models

Water Resources Research, Год журнала: 2022, Номер 59(1)

Опубликована: Дек. 22, 2022

Abstract Recent advances in global hydrological modeling yield many runoff data sets that are extensively used analyses. Here, we provide a comprehensive evaluation of simulated from 21 models, including 12 climate models CMIP6, six the Inter‐Sectoral Impact Model Inter‐Comparison Project (ISMIP2a) and three land surface Global Land Data Assimilation System (GLDAS), against observed streamflow 840 unimpaired catchments globally. Our results show (a) no model performs consistently better estimating all aspects, tend to perform more humid regions non‐cold areas; (b) interannual variability is well represented ISIMIP2a GLDAS satisfactorily capturing annual trend; (c) intra‐annual cycle reasonably captured by yet an overestimation early bias peak flow timing commonly found; (d) uncertainty leads larger estimates than induced forcing ISIMIP2a, ISIMIP2a. Finally, confirm multi‐model ensemble effective way reduce individual except for CMIP6 regarding mean magnitude trend. Overall, our findings suggest assessments/projections changes based on these outputs contain great uncertainties should be interpreted with caution, call advanced, observation‐guided techniques large‐scale applications.

Язык: Английский

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Global-scale analysis of socioeconomic impacts of coastal flooding over the 21st century

Frontiers in Marine Science, Год журнала: 2023, Номер 9

Опубликована: Янв. 16, 2023

Building on a global database of projected extreme coastal flooding over the coming century, an extensive analysis that accounts for both existing levels defences (structural measures) and two scenarios future changes in defence is undertaken to determine expected annual people affected ( EAPA ) damage EAD ). A range plausible climate change considered along with narratives socioeconomic change. We find no further adaptation, could increase from 34M people/year 2015 246M by 2100. Global 0.3% GDP today 2.9% If, however, are increased at rate which matches sea level, 2100, total reduced 119M will be factor almost three 1.1% GDP. The impacts such disproportionately affect developing world. By Asia, West Africa Egypt regions most impacted. If adaptation actions taken, many nations experience greater than 5% GDP, whilst all developed less 3%

Язык: Английский

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Exceptional stratospheric contribution to human fingerprints on atmospheric temperature

Proceedings of the National Academy of Sciences, Год журнала: 2023, Номер 120(20)

Опубликована: Май 8, 2023

In 1967, scientists used a simple climate model to predict that human-caused increases in atmospheric CO2 should warm Earth's troposphere and cool the stratosphere. This important signature of anthropogenic change has been documented weather balloon satellite temperature measurements extending from near-surface lower Stratospheric cooling also confirmed mid upper stratosphere, layer roughly 25 50 km above surface (S25 - 50). To date, however, S25 temperatures have not pattern-based attribution studies change. Here, we perform such "fingerprint" study with satellite-derived patterns extend Including information signal-to-noise ratios by factor five, markedly enhancing fingerprint detectability. Key features this global-scale human include stratospheric tropospheric warming at all latitudes, amplifying height. contrast, dominant modes internal variability smaller-scale changes lack uniform sign. These pronounced spatial differences between signal noise are accompanied large (1 2[Formula: see text]C over 1986 2022) low levels. Our results explain why "vertical fingerprinting" stratosphere yields incontrovertible evidence effects on thermal structure atmosphere.

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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Revised historical Northern Hemisphere black carbon emissions based on inverse modeling of ice core records

Nature Communications, Год журнала: 2023, Номер 14(1)

Опубликована: Янв. 17, 2023

Abstract Black carbon emitted by incomplete combustion of fossil fuels and biomass has a net warming effect in the atmosphere reduces albedo when deposited on ice snow; accurate knowledge past emissions is essential to quantify model associated global climate forcing. Although bottom-up inventories provide historical Carbon emission estimates that are widely used Earth System Models, they poorly constrained observations prior late 20th century. Here we use an objective inversion technique based detailed atmospheric transport deposition modeling reconstruct 1850 2000 from thirteen Northern Hemisphere ice-core records. We find substantial discrepancies between reconstructed existing which do not fully capture complex spatial-temporal patterns. Our findings imply changes radiative forcing necessary, with potential implications for observation-constrained sensitivity.

Язык: Английский

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Tropical Atlantic multidecadal variability is dominated by external forcing

Nature, Год журнала: 2023, Номер 622(7983), С. 521 - 527

Опубликована: Сен. 13, 2023

Язык: Английский

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