A Machine Learning Tool for Determining the Required Sample Size for GEV Fitting in Climate Applications DOI Creative Commons
Richard J. Matear, P. Jyoteeshkumar Reddy

Geophysical Research Letters, Journal Year: 2025, Volume and Issue: 52(6)

Published: March 23, 2025

Abstract Extreme climate events (ECEs) like heavy rainfall and heatwaves significantly impact society, change is altering their magnitude frequency. Generalized Value (GEV) distributions help quantify these ECEs guide human system design. We train a machine learning (ML) model using set of arbitrary GEV to estimate the sample size required determine return value with specific uncertainty. For negative shape parameter maximum extreme temperatures are bounded fewer samples needed given uncertainty than extremes which have positive unbounded values. example, if 1‐in‐20‐year heatwave event requires 400 1% uncertainty, one would need 20 different 20‐year simulations. Achieving such quantities will require extensive downscaling simulations, potentially aided by ML‐based methods increase ensemble size.

Language: Английский

The 2021 western North America heat wave among the most extreme events ever recorded globally DOI Creative Commons
Vikki Thompson, Alan Kennedy-Asser, Emily Vosper

et al.

Science Advances, Journal Year: 2022, Volume and Issue: 8(18)

Published: May 4, 2022

In June 2021, western North America experienced a record-breaking heat wave outside the distribution of previously observed temperatures. While it is clear that event was extreme, not obvious whether other areas in world have also events so far their natural variability. Using novel assessment extremes, we investigate how extreme this global context. Characterizing relative intensity an as number standard deviations from mean, remarkable, coming at over four deviations. Throughout globe, where reliable data, only five waves were found to be more since 1960. We find both reanalyses and climate projections, statistical extremes increases through time, line with mean shift due change. Regions that, by chance, had recent may less prepared for potentially imminent events.

Language: Английский

Citations

203

Globally unequal effect of extreme heat on economic growth DOI Creative Commons
Christopher W. Callahan, Justin S. Mankin

Science Advances, Journal Year: 2022, Volume and Issue: 8(43)

Published: Oct. 28, 2022

Increased extreme heat is among the clearest impacts of global warming, but economic effects waves are poorly understood. Using subnational data, metrics measuring temperature hottest several days in each year, and an ensemble climate models, we quantify effect intensity on growth globally. We find that human-caused increases have depressed output most poor tropical regions least culpable for warming. Cumulative 1992-2013 losses from anthropogenic likely fall between $5 trillion $29.3 Losses amount to 6.7% Gross Domestic Product per capita year bottom income decile, only 1.5% top decile. Our results potential inform adaptation investments demonstrate how inequality both a cause consequence unequal burden change.

Language: Английский

Citations

120

Origin, importance, and predictive limits of internal climate variability DOI Creative Commons
Flavio Lehner,

Clara Deser

Environmental Research Climate, Journal Year: 2023, Volume and Issue: 2(2), P. 023001 - 023001

Published: April 21, 2023

Abstract Adaptation to climate change has now become a necessity for many regions. Yet, adaptation planning at regional scales over the next few decades is challenging given contingencies originating from combination of different sources projection uncertainty, chief among them internal variability. Here, we review causes and consequences variability, how it can be quantified accounted in uncertainty assessments, what research questions remain most pertinent better understand its predictive limits science society. This perspective argues putting variability into spotlight intensifying collaborations between modeling application communities.

Language: Английский

Citations

48

How to stop being surprised by unprecedented weather DOI Creative Commons
Timo Kelder, Dorothy Heinrich, Lisette Klok

et al.

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: March 10, 2025

Abstract We see unprecedented weather causing widespread impacts across the world. In this perspective, we provide an overview of methods that help anticipate hazards can contribute to stop being surprised. then discuss disaster management and climate adaptation practices, their gaps, how may build resilience. stimulate thinking about transformative as a foundation for long-term resilience weather, supported by incremental through upgrading existing infrastructure, reactive short-term early action response. Because in end, should take responsibility rather than surprised weather.

Language: Английский

Citations

3

Growing Threats From Unprecedented Sequential Flood‐Hot Extremes Across China DOI
Zhen Liao, Yang Chen,

Wei Li

et al.

Geophysical Research Letters, Journal Year: 2021, Volume and Issue: 48(18)

Published: Sept. 8, 2021

Abstract When multiple extremes occur in rapid sequence, their impacts cascade to cause disproportionate damages. However, the prevalence of univariate definitions and inability identify low‐likelihood events short observations/simulations leave knowledge on sequential sparse. Leveraging two initial‐condition large ensembles, we project future changes historically unprecedented flood‐hot China. Results show that despite dozens 1 50‐year floods hot more than 2,000 years historical simulations, sequenced occurrence within a week has no precedent. This out‐of‐ordinary configuration is projected be increasingly possible across China, with earlier emergence larger frequency increases expected Southwest Southeast The direction, spatial extent, magnitude cannot explained by internal variability alone, though it potential modulate human‐caused timing magnitude.

Language: Английский

Citations

65

Unprecedented Heatwave in Western North America during Late June of 2021: Roles of Atmospheric Circulation and Global Warming DOI Creative Commons
Chunzai Wang, Jiayu Zheng, Wei Lin

et al.

Advances in Atmospheric Sciences, Journal Year: 2022, Volume and Issue: 40(1), P. 14 - 28

Published: July 22, 2022

Abstract An extraordinary and unprecedented heatwave swept across western North America (i.e., the Pacific Northwest) in late June of 2021, resulting hundreds deaths, a massive die-off sea creatures off coast, horrific wildfires. Here, we use observational data to find atmospheric circulation variabilities Arctic-Pacific-Canada patterns that co-occurred with development mature phases heatwave, as well pattern, which coincided decaying eastward movement heatwave. Climate models from Coupled Model Intercomparison Project (Phase 6) are not designed simulate particular event like this one. Still, show greenhouse gases main reason for long-term increase average daily maximum temperature past future.

Language: Английский

Citations

45

Demystifying global climate models for use in the life sciences DOI Creative Commons
David S. Schoeman, Alex Sen Gupta, Cheryl S. Harrison

et al.

Trends in Ecology & Evolution, Journal Year: 2023, Volume and Issue: 38(9), P. 843 - 858

Published: May 11, 2023

Language: Английский

Citations

39

Storylines for unprecedented heatwaves based on ensemble boosting DOI Creative Commons
Erich Fischer, Urs Beyerle, Luna Bloin-Wibe

et al.

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: Aug. 22, 2023

Recent temperature extremes have shattered previously observed records, reaching intensities that were inconceivable before the events. Could possibility of an event with such unprecedented intensity as 2021 Pacific Northwest heatwave been foreseen, based on climate model information available event? scientific community quantified its potential current generation models? Here, we demonstrate how ensemble boosting approach can be used to generate physically plausible storylines a hotter than in Northwest. We also show heatwaves much greater ever are possible other locations like Greater Chicago and Paris regions. In order establish confidence 'black swan'-type events, different lines evidence need combined along process understanding make this robust actionable for stakeholders.

Language: Английский

Citations

38

Observational and model evidence together support wide-spread exposure to noncompensable heat under continued global warming DOI Creative Commons
Carter M. Powis, David Byrne, Zachary Zobel

et al.

Science Advances, Journal Year: 2023, Volume and Issue: 9(36)

Published: Sept. 8, 2023

As our planet warms, a critical research question is when and where temperatures will exceed the limits of what human body can tolerate. Past modeling efforts have investigated 35°C wet-bulb threshold, proposed as theoretical upper limit to survivability taking into account physiological behavioral adaptation. Here, we conduct an extreme value theory analysis weather station observations climate model projections investigate emergence empirically supported heat compensability limit. We show that hottest parts world already experience these extremes on limited basis under moderate continued warming every continent, except Antarctica, see rapid increase in their extent frequency. To conclude, discuss consequences this noncompensable need for incorporating different thermal adaptation planning.

Language: Английский

Citations

27

Multi-year drought storylines for Europe and North America from an iteratively perturbed global climate model DOI Creative Commons
Claudia Gessner, Erich Fischer, Urs Beyerle

et al.

Weather and Climate Extremes, Journal Year: 2022, Volume and Issue: 38, P. 100512 - 100512

Published: Sept. 27, 2022

Throughout history, Europe and North America have experienced intense long-lasting droughts with large impacts on society ecosystem such as the recent drought 2018/2019 historical 1540 in Europe, or US Dust Bowl of 1930s. To increase resilience develop adaptation strategies to extreme droughts, it is important understand how dry a worst-case would be long take recover from it. This study introduces evaluates methodological framework generate coherent climate model-based storylines different severities for locations. The so-called iterative ensemble resampling method repeatedly runs ensembles only keeps those members, which minimize local precipitation. are developed fully coupled global model CESM1. first part analysis demonstrates feasibility by generating some most possible. Using stringent precipitation criteria, accumulated reduced 80% relative long-term average western 77% central America, respectively, over multiple years. number days Western European storyline corresponds estimates reconstructed Central Europe. low induces soil moisture deficit that physically consistent but beyond high return levels estimated based purely statistically fitted generalized value (GEV) distributions. In second part, used setup assess recovery time deficits. Over driest regions well eastern recovers period few months up more than five years, depending mean atmospheric circulation rather strength deficit. can very rare conduct idealized experiments. When lowering selection criteria precipitation, less likely occur real world. approach help stress test socio-economic system potential periods.

Language: Английский

Citations

33