Present-day constraint for tropical Pacific precipitation changes due to global warming in CMIP5 models

Anomalous rainfall in the tropical Pacific driven by El Niño–Southern Oscillation (ENSO) is a crucial pathway of ENSO’s global impacts. The changes in ENSO rainfall under global warming vary among the models, even though previous studies have shown that many models project that ENSO rainfall will likely intensify and shift eastward in response to global warming. The present study evaluates the robustness of the changes in ENSO rainfall in 32 CMIP5 models forced under the representative concentration pathway 8.5 (RCP8.5) scenario. The robust increase in mean-state moisture dominates the robust intensification of ENSO rainfall. The uncertain amplitude changes in ENSO-related SST variability are the largest source of the uncertainty in ENSO rainfall changes through influencing the amplitude changes in ENSO-driven circulation variability, whereas the structural changes in ENSO SST and ENSO circulation enhancement in the central Pacific are more robust than the amplitude changes. The spatial pattern of the mean-state SST changes—the departure of local SST changes from the tropical mean—with an El Niño–like pattern is a relatively robust factor, although it also contains pronounced intermodel differences. The intermodel spread of historical ENSO circulation is another noteworthy source of the uncertainty in ENSO rainfall changes. The intermodel standard deviation of ENSO rainfall changes increases along with the increase in global-mean surface temperature. However, the robustness of enhanced ENSO rainfall changes in the central-eastern Pacific is almost unchanged, whereas the eastward shift of ENSO rainfall is increasingly robust along with the increase in global-mean surface temperature.

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Time-Varying Response of ENSO-Induced Tropical Pacific Rainfall to Global Warming in CMIP5 Models. Part I: Multimodel Ensemble Results

Journal of Climate ◽

10.1175/jcli-d-16-0058.1 ◽

2016 ◽

Vol 29 (16) ◽

pp. 5763-5778 ◽

Cited By ~ 21

Author(s):

Ping Huang

Keyword(s):

Global Warming ◽

El Niño ◽

El Nino ◽

Rainfall Variability ◽

Tropical Pacific ◽

Cmip5 Models ◽

Global Mean Temperature ◽

Mean Temperature ◽

Global Mean ◽

Mean State

Abstract El Niño–Southern Oscillation (ENSO) is one of the most important drivers of climatic variability on the global scale. Much of this variability arises in response to ENSO-driven changes in tropical Pacific rainfall. Previous research has shown that the ENSO-driven tropical Pacific rainfall variability can shift east and intensify in response to global warming, even if ENSO-related SST variability remains unchanged. Here, the twenty-first century changes in ENSO-driven tropical Pacific rainfall variability in 32 CMIP5 models forced under the representative concentration pathway 8.5 (RCP8.5) scenario are examined, revealing that the pattern of changes in ENSO-driven rainfall is not only gradually enhanced but also shifts steadily eastward along with the global-mean temperature increase. Using a recently developed moisture budget decomposition method, it is shown that the projected changes in ENSO-driven rainfall variability in the tropical Pacific can be primarily attributed to a projected increase in both mean-state surface moisture and spatially relative changes in mean-state SST, defined as the departure of local SST changes from the tropical mean. The enhanced moisture increase enlarges the thermodynamic component of ENSO rainfall changes. The enhanced El Niño–like changes in mean-state SST steadily move the dynamic component of changes in ENSO-driven rainfall variability to the central-eastern Pacific, along with increasing global-mean temperature.

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South American precipitation changes simulated by PMIP3/CMIP5 models during the Little Ice Age and the recent global warming period

International Journal of Climatology ◽

10.1002/joc.5449 ◽

2018 ◽

Vol 38 (6) ◽

pp. 2638-2650 ◽

Cited By ~ 2

Author(s):

Leandro B. Díaz ◽

Carolina S. Vera

Keyword(s):

Global Warming ◽

Little Ice Age ◽

Ice Age ◽

Cmip5 Models ◽

South American ◽

Warming Period ◽

Precipitation Changes

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Changes in Independency between Two Types of El Niño Events under a Greenhouse Warming Scenario in CMIP5 Models

Journal of Climate ◽

10.1175/jcli-d-14-00721.1 ◽

2015 ◽

Vol 28 (19) ◽

pp. 7561-7575 ◽

Cited By ~ 2

Author(s):

Yoo-Geun Ham ◽

Yerim Jeong ◽

Jong-Seong Kug

Keyword(s):

Global Warming ◽

El Niño ◽

El Nino ◽

Western Pacific ◽

Cmip5 Models ◽

Greenhouse Warming ◽

Central Pacific ◽

El Niño Events ◽

The Western Pacific ◽

El Nino Events

Abstract This study uses archives from phase 5 of the Coupled Model Intercomparison Project (CMIP5) to investigate changes in independency between two types of El Niño events caused by greenhouse warming. In the observations, the independency between cold tongue (CT) and warm pool (WP) El Niño events is distinctively increased in recent decades. The simulated changes in independency between the two types of El Niño events according to the CMIP5 models are quite diverse, although the observed features are simulated to some extent in several climate models. It is found that the climatological change after global warming is an essential factor in determining the changes in independency between the two types of El Niño events. For example, the independency between these events is increased after global warming when the climatological precipitation is increased mainly over the equatorial central Pacific. This climatological precipitation increase extends convective response to the east, particularly for CT El Niño events, which leads to greater differences in the spatial pattern between the two types of El Niño events to increase the El Niño independency. On the contrary, in models with decreased independency between the two types of El Niño events after global warming, climatological precipitation is increased mostly over the western Pacific. This confines the atmospheric response to the western Pacific in both El Niño events; therefore, the similarity between them is increased after global warming. In addition to the changes in the climatological state after global warming, a possible connection of the changes in the El Niño independency with the historical mean state is discussed in this paper.

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A stronger versus weaker Walker: understanding model differences in fast and slow tropical Pacific responses to global warming

Climate Dynamics ◽

10.1007/s00382-021-05818-5 ◽

2021 ◽

Author(s):

Ulla K. Heede ◽

Alexey V. Fedorov ◽

Natalie J. Burls

Keyword(s):

Global Warming ◽

Tropical Pacific

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A Link between the Hiatus in Global Warming and North American Drought

Journal of Climate ◽

10.1175/jcli-d-14-00616.1 ◽

2015 ◽

Vol 28 (9) ◽

pp. 3834-3845 ◽

Cited By ~ 69

Author(s):

Thomas L. Delworth ◽

Fanrong Zeng ◽

Anthony Rosati ◽

Gabriel A. Vecchi ◽

Andrew T. Wittenberg

Keyword(s):

Global Warming ◽

North America ◽

Surface Temperature ◽

North American ◽

Radiative Forcing ◽

Tropical Pacific ◽

Global Warming Hiatus ◽

Warming Hiatus ◽

The Impact ◽

The Tropical Pacific

Abstract Portions of western North America have experienced prolonged drought over the last decade. This drought has occurred at the same time as the global warming hiatus—a decadal period with little increase in global mean surface temperature. Climate models and observational analyses are used to clarify the dual role of recent tropical Pacific changes in driving both the global warming hiatus and North American drought. When observed tropical Pacific wind stress anomalies are inserted into coupled models, the simulations produce persistent negative sea surface temperature anomalies in the eastern tropical Pacific, a hiatus in global warming, and drought over North America driven by SST-induced atmospheric circulation anomalies. In the simulations herein the tropical wind anomalies account for 92% of the simulated North American drought during the recent decade, with 8% from anthropogenic radiative forcing changes. This suggests that anthropogenic radiative forcing is not the dominant driver of the current drought, unless the wind changes themselves are driven by anthropogenic radiative forcing. The anomalous tropical winds could also originate from coupled interactions in the tropical Pacific or from forcing outside the tropical Pacific. The model experiments suggest that if the tropical winds were to return to climatological conditions, then the recent tendency toward North American drought would diminish. Alternatively, if the anomalous tropical winds were to persist, then the impact on North American drought would continue; however, the impact of the enhanced Pacific easterlies on global temperature diminishes after a decade or two due to a surface reemergence of warmer water that was initially subducted into the ocean interior.

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Physical forcing and the dynamics of the pelagic ecosystem in the eastern tropical Pacific: simulations with ENSO-scale and global-warming climate drivers

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f03-100 ◽

2003 ◽

Vol 60 (9) ◽

pp. 1161-1175 ◽

Cited By ~ 49

Author(s):

George M Watters ◽

Robert J Olson ◽

Robert C Francis ◽

Paul C Fiedler ◽

Jeffrey J Polovina ◽

...

Keyword(s):

Global Warming ◽

Phytoplankton Biomass ◽

Southern Oscillation ◽

Tropical Pacific ◽

Trophic Levels ◽

Eastern Tropical Pacific ◽

Ecosystem Models ◽

Pelagic Ecosystem ◽

Physical Forcing ◽

Physical Effects

We used a model of the pelagic ecosystem in the eastern tropical Pacific Ocean to explore how climate variation at El Niño Southern Oscillation (ENSO) scales might affect animals at middle and upper trophic levels. We developed two physical-forcing scenarios: (1) physical effects on phytoplankton biomass and (2) simultaneous physical effects on phytoplankton biomass and predator recruitment. We simulated the effects of climate-anomaly pulses, climate cycles, and global warming. Pulses caused oscillations to propagate through the ecosystem; cycles affected the shapes of these oscillations; and warming caused trends. We concluded that biomass trajectories of single populations at middle and upper trophic levels cannot be used to detect bottom-up effects, that direct physical effects on predator recruitment can be the dominant source of interannual variability in pelagic ecosystems, that such direct effects may dampen top-down control by fisheries, and that predictions about the effects of climate change may be misleading if fishing mortality is not considered. Predictions from ecosystem models are sensitive to the relative strengths of indirect and direct physical effects on middle and upper trophic levels.

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Spatiotemporal Variability in Extreme Precipitation in China from Observations and Projections

Water ◽

10.3390/w10081089 ◽

2018 ◽

Vol 10 (8) ◽

pp. 1089 ◽

Cited By ~ 9

Author(s):

Yifeng Peng ◽

Xiang Zhao ◽

Donghai Wu ◽

Bijian Tang ◽

Peipei Xu ◽

...

Keyword(s):

Global Warming ◽

Extreme Precipitation ◽

Spatiotemporal Variability ◽

Tibet Plateau ◽

Cmip5 Models ◽

Ecological Processes ◽

The Past ◽

Spatiotemporal Characteristics ◽

Extreme Precipitation Events ◽

Precipitation Events

Extreme precipitation events, which have intensified with global warming over the past several decades, will become more intense in the future according to model projections. Although many studies have been performed, the occurrence patterns for extreme precipitation events in past and future periods in China remain unresolved. Additionally, few studies have explained how extreme precipitation events developed over the past 58 years and how they will evolve in the next 90 years as global warming becomes much more serious. In this paper, we evaluated the spatiotemporal characteristics of extreme precipitation events using indices for the frequency, quantity, intensity, and proportion of extreme precipitation, which were proposed by the World Meteorological Organization. We simultaneously analyzed the spatiotemporal characteristics of extreme precipitation in China from 2011 to 2100 using data obtained from the Coupled Model Intercomparison Project Phase 5 (CMIP5) models. Despite the fixed threshold, 95th percentile precipitation values were also used as the extreme precipitation threshold to reduce the influence of various rainfall events caused by different geographic locations; then, eight extreme precipitation indices (EPIs) were calculated to evaluate extreme precipitation in China. We found that the spatial characteristics of the eight EPIs exhibited downward trends from south to north. In the periods 1960–2017 and 2011–2100, trends in the EPIs were positive, but there were differences between different regions. In the past 58 years, the extreme precipitation increased in the northwest, southeast, and the Tibet Plateau of China, while decreased in northern China. Almost all the trends of EPIs are positive in the next two periods (2011–2055 and 2056–2100) except for some EPIs, such as intensity of extreme precipitation, which decrease in southeastern China in the second period (2056–2100). This study suggests that the frequency of extreme precipitation events in China will progressively increase, which implies that a substantial burden will be placed on social economies and terrestrial ecological processes.

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