Decadal variability of winter warm Arctic‐cold Eurasia dipole patterns modulated by Pacific Decadal Oscillation and Atlantic Multidecadal Oscillation

This is the second part of a three-part paper on North American climate in phase 5 of the Coupled Model Intercomparison Project (CMIP5) that evaluates the twentieth-century simulations of intraseasonal to multidecadal variability and teleconnections with North American climate. Overall, the multimodel ensemble does reasonably well at reproducing observed variability in several aspects, but it does less well at capturing observed teleconnections, with implications for future projections examined in part three of this paper. In terms of intraseasonal variability, almost half of the models examined can reproduce observed variability in the eastern Pacific and most models capture the midsummer drought over Central America. The multimodel mean replicates the density of traveling tropical synoptic-scale disturbances but with large spread among the models. On the other hand, the coarse resolution of the models means that tropical cyclone frequencies are underpredicted in the Atlantic and eastern North Pacific. The frequency and mean amplitude of ENSO are generally well reproduced, although teleconnections with North American climate are widely varying among models and only a few models can reproduce the east and central Pacific types of ENSO and connections with U.S. winter temperatures. The models capture the spatial pattern of Pacific decadal oscillation (PDO) variability and its influence on continental temperature and West Coast precipitation but less well for the wintertime precipitation. The spatial representation of the Atlantic multidecadal oscillation (AMO) is reasonable, but the magnitude of SST anomalies and teleconnections are poorly reproduced. Multidecadal trends such as the warming hole over the central–southeastern United States and precipitation increases are not replicated by the models, suggesting that observed changes are linked to natural variability.

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Decadal variability in the occurrence of wintertime haze in central eastern China tied to the Pacific Decadal Oscillation

Scientific Reports ◽

10.1038/srep27424 ◽

2016 ◽

Vol 6 (1) ◽

Cited By ~ 41

Author(s):

Sen Zhao ◽

Jianping Li ◽

Cheng Sun

Keyword(s):

Pacific Decadal Oscillation ◽

Decadal Variability ◽

Eastern China ◽

The Pacific ◽

Central Eastern

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On the Mechanisms of Pacific Decadal Oscillation Modulation in a Warming Climate

Journal of Climate ◽

10.1175/jcli-d-18-0337.1 ◽

2019 ◽

Vol 32 (5) ◽

pp. 1443-1459 ◽

Cited By ~ 4

Author(s):

Tao Geng ◽

Yun Yang ◽

Lixin Wu

Keyword(s):

Growth Rate ◽

Global Warming ◽

Pacific Decadal Oscillation ◽

Decadal Variability ◽

Coupled Model ◽

Growth Time ◽

Coupled Mode ◽

Warming Climate ◽

The Pacific ◽

Intercomparison Project

Abstract Changes of the Pacific decadal oscillation (PDO) under global warming are investigated by using outputs from phase 5 of the Coupled Model Intercomparison Project (CMIP5) and a theoretical midlatitude air–sea coupled model. In a warming climate, the decadal variability of the PDO is found to be significantly suppressed, with the amplitude reduced and the decadal cycle shifted toward a higher-frequency band. We used the theoretical model put forward by Goodman and Marshall (herein the GM model) to underpin the potential mechanisms. The GM model exhibits a growing coupled mode that resembles the simulated PDO. It is found that the suppression of the PDO appears to be associated with the acceleration of Rossby waves due to the enhanced oceanic stratification under global warming. This shortens the PDO period and reduces PDO amplitude by limiting the growth time of the coupled mode. The GM model also suggests that the increase of growth rate due to strengthening of oceanic stratification tends to magnify the PDO amplitude, counteracting the Rossby wave effect. This growth rate influence, however, plays a secondary role.

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Gulf Stream Excursions and Sectional Detachments Generate the Decadal Pulses in the Atlantic Multidecadal Oscillation

Journal of Climate ◽

10.1175/jcli-d-17-0010.1 ◽

2018 ◽

Vol 31 (7) ◽

pp. 2853-2870 ◽

Cited By ~ 19

Author(s):

Sumant Nigam ◽

Alfredo Ruiz-Barradas ◽

Léon Chafik

Keyword(s):

North Atlantic ◽

Gulf Stream ◽

Decadal Variability ◽

Low Frequency ◽

Atlantic Multidecadal Oscillation ◽

Subpolar Gyre ◽

Western Basin ◽

Salinity Anomaly ◽

Meridional Displacement ◽

Great Salinity Anomaly

Decadal pulses within the lower-frequency Atlantic multidecadal oscillation (AMO) are a prominent but underappreciated AMO feature, representing decadal variability of the subpolar gyre (e.g., the Great Salinity Anomaly of the 1970s) and wielding notable influence on the hydroclimate of the African and American continents. Here clues are sought into their origin in the spatiotemporal development of the Gulf Stream’s (GS) meridional excursions and sectional detachments apparent in the 1954–2012 record of ocean surface and subsurface salinity and temperature observations. The GS excursions are tracked via meridional displacement of the 15°C isotherm at 200-m depth—the GS index—whereas the AMO’s decadal pulses are targeted through the AMO tendency, which implicitly highlights the shorter time scales of the AMO index. The GS’s northward shift is shown to be preceded by the positive phase of the low-frequency North Atlantic Oscillation (LF-NAO) and followed by a positive AMO tendency by 1.25 and 2.5 years, respectively. The temporal phasing is such that the GS’s northward shift is nearly concurrent with the AMO’s cold decadal phase (cold, fresh subpolar gyre). Ocean–atmosphere processes that can initiate phase reversal of the gyre state are discussed, starting with the reversal of the LF-NAO, leading to a mechanistic hypothesis for decadal fluctuations of the subpolar gyre. According to the hypothesis, the fluctuation time scale is set by the self-feedback of the LF-NAO from its influence on SSTs in the seas around Greenland, and by the cross-basin transit of the GS’s detached eastern section; the latter is produced by the southward intrusion of subpolar water through the Newfoundland basin, just prior to the GS’s northward shift in the western basin.

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Factors Associated with Decadal Variability in Great Plains Summertime Surface Temperatures

Journal of Climate ◽

10.1175/jcli-d-11-00713.1 ◽

2013 ◽

Vol 26 (1) ◽

pp. 343-350 ◽

Cited By ~ 21

Author(s):

Scott J. Weaver

Keyword(s):

Surface Temperature ◽

Great Plains ◽

Decadal Variability ◽

Atlantic Multidecadal Oscillation ◽

Regional Warming ◽

Factors Associated ◽

Sst Variability ◽

The Pacific ◽

Low Level Jet ◽

Decadal Climate

Abstract Decadal variability of summertime Great Plains surface temperature is probed from the perspective of the Great Plains low-level jet (GPLLJ). GPLLJ variability modes 2 and 5 are shown to be most influential on the evolution and magnitude of Great Plains surface temperature anomalies over the latter half of the twentieth century, including the development of the summertime warming hole and are further linked to the Pacific decadal oscillation (PDO) and Atlantic multidecadal oscillation (AMO), respectively. The connection between GPLLJ variability and Great Plains surface temperature is strongest when the PDO and AMO are oppositely phased, and in the case of the warming hole, a preference for a positive (negative) PDO (AMO). The influence of remote SST variability on the central U.S. warming hole is broadly consistent with previous modeling studies. However, the pivotal role that GPLLJ variability plays in linking the hemispheric-wide SST variability (through the AMO and PDO) to the regional warming hole is an expanded and clarified perspective. These findings unify the results of recent studies from the U.S. Climate Variability and Predictability (CLIVAR) Drought Working Group and have implications for decadal climate prediction efforts.

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Effects of Atlantic multidecadal oscillation and Pacific decadal oscillation on interdecadal variability of fog frequency in autumn–winter season in Southwest China

International Journal of Climatology ◽

10.1002/joc.7353 ◽

2021 ◽

Author(s):

Peng Liu ◽

Ying Zhang ◽

Mingyue Tang

Keyword(s):

Pacific Decadal Oscillation ◽

Southwest China ◽

Winter Season ◽

Atlantic Multidecadal Oscillation ◽

Interdecadal Variability

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A New Statistical Model for Predicting Seasonal North Atlantic Hurricane Activity

Weather and Forecasting ◽

10.1175/waf-d-14-00156.1 ◽

2015 ◽

Vol 30 (3) ◽

pp. 730-741 ◽

Cited By ~ 10

Author(s):

Kyle Davis ◽

Xubin Zeng ◽

Elizabeth A. Ritchie

Keyword(s):

Statistical Model ◽

North Atlantic ◽

Decadal Variability ◽

Poor Performance ◽

Seasonal Prediction ◽

Atlantic Multidecadal Oscillation ◽

Hybrid Models ◽

Colorado State University ◽

Atlantic Hurricane ◽

The North

Abstract Statistical, dynamical, and statistical–dynamical hybrid models have been developed in past decades for the seasonal prediction of North Atlantic hurricane numbers. These models’ prediction skills show considerable decadal variability, with particularly poor performance in the past few years. Here, environmental factors that affect hurricane activities are reevaluated to develop a new statistical model for seasonal prediction by 1 June of each year. The predictors include the April–May multivariate ENSO index (MEI) conditioned upon the Atlantic multidecadal oscillation (AMO) index, the power of the average zonal pseudo–wind stress across the North Atlantic in May, and the average March–May tropical Atlantic sea surface temperature. When compared to the actual number of hurricanes each year from 1950 to 2013, this model has a root-mean-square error (RMSE) of 1.91 with a correlation coefficient of 0.71. It shows a 39% improvement in RMSE over a no-skill metric (based on the 5-yr running mean of seasonal hurricane counts) for the period 2001–13. It also outperforms three statistical–dynamical hybrid models [CPC, Colorado State University (CSU), and Tropical Storm Risk (TSR)] by more than 25% for the same period. Furthermore, two approaches are developed to provide the uncertainty ranges around the predicted (deterministic) hurricane number per season that better encompass the range of uncertainty than does the standard method of adding/subtracting a standard deviation of the errors.

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The Pacific Decadal Oscillation less predictable under greenhouse warming

10.5194/egusphere-egu2020-6399 ◽

2020 ◽

Author(s):

Shujun Li

Keyword(s):

Pacific Decadal Oscillation ◽

Decadal Variability ◽

Coupled Model ◽

Influential Factor ◽

Growth Time ◽

Greenhouse Warming ◽

Surface Warming ◽

The North ◽

Global Mean Temperature ◽

The Pacific

<p><strong>The Pacific Decadal Oscillation (PDO) is the most prominent form of decadal variability over the North Pacific, characterized by its horseshoe-like sea surface temperature (SST) anomaly pattern. The PDO exerts a substantial influence on marine ecosystems, fisheries, and agriculture. Through modulating global mean temperature, the phase shift of the PDO at the end of the 20th century is suggested to be an influential factor in the recent surface warming hiatus. Therefore, determining the predictability of the PDO in a warming climate is of great importance. By analyzing future climate under different emission scenarios simulated by the Coupled Model Intercomparison Project phase 5 (CMIP5), we show that the prediction lead time and the associated amplitude of the PDO decreases sharply under greenhouse warming conditions. This decrease is largely attributable to a warming-induced intensification of oceanic stratification, which accelerates propagation of Rossby waves, shortening the PDO lifespan and suppressing its amplitude by limiting its growth time. Our results suggest that greenhouse warming will make prediction of the PDO more challenging, with far-reaching ramifications.&#160;&#160; </strong></p>

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Sea level trends in Southeast Asian seas

Climate of the Past ◽

10.5194/cp-11-743-2015 ◽

2015 ◽

Vol 11 (5) ◽

pp. 743-750 ◽

Cited By ~ 15

Author(s):

M. W. Strassburg ◽

B. D. Hamlington ◽

R. R. Leben ◽

P. Manurung ◽

J. Lumban Gaol ◽

...

Keyword(s):

Sea Level ◽

Pacific Decadal Oscillation ◽

Decadal Variability ◽

Southeast Asian ◽

Global Ocean ◽

Satellite Altimeter ◽

Trade Winds ◽

The Past ◽

The Pacific ◽

Regional Sea Level

Abstract. Southeast Asian seas span the largest archipelago in the global ocean and provide a complex oceanic pathway connecting the Pacific and Indian oceans. The Southeast Asian sea regional sea level trends are some of the highest observed in the modern satellite altimeter record that now spans almost 2 decades. Initial comparisons of global sea level reconstructions find that 17-year sea level trends over the past 60 years exhibit good agreement with decadal variability associated with the Pacific Decadal Oscillation and related fluctuations of trade winds in the region. The Southeast Asian sea region exhibits sea level trends that vary dramatically over the studied time period. This historical variation suggests that the strong regional sea level trends observed during the modern satellite altimeter record will abate as trade winds fluctuate on decadal and longer timescales. Furthermore, after removing the contribution of the Pacific Decadal Oscillation (PDO) to sea level trends in the past 20 years, the rate of sea level rise is greatly reduced in the Southeast Asian sea region. As a result of the influence of the PDO, the Southeast Asian sea regional sea level trends during the 2010s and 2020s are likely to be less than the global mean sea level (GMSL) trend if the observed oscillations in wind forcing and sea level persist. Nevertheless, long-term sea level trends in the Southeast Asian seas will continue to be affected by GMSL rise occurring now and in the future.

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