Influences of ENSO on boreal summer intraseasonal oscillation over the western Pacific in decaying summer

Chen, Xiong; Li, Chongyin; Li, Xin

doi:10.1007/s00382-020-05183-9

Cited by 12 publications

(7 citation statements)

References 52 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…That is, the intraseasonal dSST shows a weaker minimum/maximum during the convectively active/suppressed phase (0.2/0.47°C) but a stronger oscillation (0.27°C) during El Niño developing summers than that during El Niño decaying summers (0.34/0.58°C with a 0.24°C range). This can be explained by the prominent antisymmetric features of the circulation anomalies between the two summer types (Chen et al ., 2020). During El Niño decaying summers, the TWP is controlled by an abnormal anticyclonic circulation, which could lead to moisture divergence and the suppression of convection.…”

Section: Resultsmentioning

confidence: 99%

Modulation of observed sea surface temperature variation by the quasi‐biweekly oscillation in the tropical western Pacific during boreal summer

Yang

et al. 2021

Intl Journal of Climatology

View full text Add to dashboard Cite

Using 17‐year in situ buoy observations, this study investigates how sea surface temperature (SST) over the tropical western Pacific Ocean is modulated by the quasi‐biweekly oscillation (QBWO) during boreal summer. The 10‐buoy mean phase‐by‐phase composites of SST indicate that SST evolution lags behind the convection cycle by approximately one quarter, with the maximum SST occurring in Phase −90° (29.68°C) and the minimum SST occurring in Phase 90° (29.37°C). The diurnal cycle of SST (dSST) is in phase with the convection cycle, with the minimum dSST occurring during the convectively active phase (0.34°C) and the maximum dSST occurring during the convectively suppressed phase (0.61°C). The fluctuation in the dSST reaches 0.27°C, which is similar to that in the SST (0.31°C). This kind of oscillation can be well explained by the evolution of the sea surface forcing parameters, especially the shortwave radiation and wind speeds, observed from the buoys. In addition, the composite range of the dSST suggests an interesting asymmetry between Phase −90° and 90°. The interaction of the background summer mean state and the 10–30‐day intraseasonal anomalies causes the asymmetry in wind speed between Phase −90° and 90°, which in turn results in the asymmetry in the dSST between these two phases. Since QBWOs are more likely to occur during El Niño developing summers than during El Niño decaying summers, the 10–30‐day intraseasonal SST and dSST variances during El Niño developing summers are stronger than those during El Niño decaying summers.

show abstract

Section: Resultsmentioning

confidence: 99%

Modulation of observed sea surface temperature variation by the quasi‐biweekly oscillation in the tropical western Pacific during boreal summer

Yang

et al. 2021

Intl Journal of Climatology

View full text Add to dashboard Cite

show abstract

“…Recently, there are increasing researches suggesting that the change in boreal summer solar insolation is not the direct factor in EASM change (Chiang et al, 2020;Xu et al, 2020). As one of the main processes that regulates the interannual variability of the atmospheric circulation at intercontinental and global scales, ENSO has been widely studied (Chen, Lian, et al, 2015;Chen et al, 2020;McPhaden et al, 2006). Western Pacific subtropical high (WPSH) is a high-pressure system in the western subtropical North Pacific which plays an important role in summer precipitation in East Asia (Rong Hua et al, 2006;Wu & Zhou, 2008;Yu et al, 2019).…”

Section: Possible Forcing Mechanisms Of Easm and Enso In Taiwan Islandmentioning

confidence: 99%

Paleofire, Vegetation, and Climate Reconstructions of the Middle to Late Holocene From Lacustrine Sediments of the Toushe Basin, Taiwan

Huang

Chyi

et al. 2020

Geophysical Research Letters

View full text Add to dashboard Cite

We identified four climatic stages between 6.2 and 1.3 cal kyr before present (BP) based on pollen and charcoal concentrations by high-resolution Accelerated mass spectrometer (AMS) 14 C-dated sediment profile from Taiwan's Toushe Basin. From 6.2 to 4.6 cal kyr BP, the region was warm-wet with infrequent wildfires and dominant subtropical evergreen broad-leaved forests. The climate was cooler-drier from 4.6 to 3.0 cal kyr BP, with a decline in forest and increased fire frequency. From 3.0 to 2.1 cal kyr BP, climate further cooled and dried, with the development of alpine meadows and higher fire frequency. The region became warmer and wetter from 2.1 to 1.3 cal kyr BP, accompanied by forest recovery. Climatic changes were linked to changes in East Asia Summer Monsoon intensity, which is mainly controlled by solar radiation. Wildfires were likely controlled by precipitation variability that is influenced by East Asia Summer Monsoon and El Niño-Southern Oscillation. Toushe Basin experienced drought conditions and frequent wildfires during the El Niño years. Plain Language Summary The purpose of our study is to reveal the relationship between paleoclimate, vegetation, and wildfire. The study area is located in the Toushe Basin, central Taiwan. Through palynological and charcoal analysis, the vegetation, climate, and wildfire history of the past 6,000 to 1,000 years in the study area were reconstructed. The study found that after 4,600 years, the East Asian summer monsoon continued to weaken until approximately 2,000 years ago, during which time the climate was dry and cool, and wildfires were frequent. In addition, it is found that the climate in this region is mainly controlled by the changes in solar radiation. The cycle of climate change coincides with that of solar activity. In El Niño years, the Toushe Basin was dry and frequent wildfires occurred.

show abstract

“…We further investigate differences in northward propagation of BSISO between E‐DV and E‐DC. Several studies (X. Chen et al., 2020; Teng & Wang, 2003) have demonstrated the northward propagation of BSISO activity in the Indian Ocean is less affected by ENSO. Our results are also similar to those (figure not shown).…”

Section: Characteristics Of Bsiso In E‐dv and E‐dc Summersmentioning

confidence: 99%

“…The BSISO convective activities in the western Pacific during La Niña summers are enhanced compared to those in El Niño summers (Lin, 2019). The ENSO modulation of BSISO activities depends on the location of BSISO convection (X. Chen et al., 2020). The northward‐propagating BSISO in the Indian Ocean is less sensitive to ENSO than the western Pacific because the ENSO‐induced circulation change is merely a small fraction of the mean monsoon over the Indian Ocean.…”

Section: Introductionmentioning

confidence: 99%

Dominant Processes for Dependence of Boreal Summer Intraseasonal Oscillation on El Niño Phases

Lee

Yang

et al. 2022

Geophysical Research Letters

View full text Add to dashboard Cite

Boreal summer intraseasonal oscillation (BSISO) strongly interacts with background mean fields and tends to be stronger and longer in its northward propagation during La Niña than El Niño summers. However, BSISO dependence on El Niño‐Southern Oscillation phase has not been well understood. Here, we show that BSISO‐related convections are stronger and more organized with northward propagation on 30–60‐day timescales during El Niño developing (E‐DV) than decaying (E‐DC) summers over the western Pacific. The easterly vertical shear, responsible for the next vorticity generation north of the BSISO convection, in the E‐DV (E‐DC) remarkably increases (decreases) due to the enhanced (weakened) upper‐level easterly anomaly. The air‐sea interaction in E‐DV gets stronger due to the larger meridional gradient of sea surface temperature, amplifying northward propagation than in E‐DC.

show abstract

Influences of ENSO on boreal summer intraseasonal oscillation over the western Pacific in decaying summer

Cited by 12 publications

References 52 publications

Modulation of observed sea surface temperature variation by the quasi‐biweekly oscillation in the tropical western Pacific during boreal summer

Modulation of observed sea surface temperature variation by the quasi‐biweekly oscillation in the tropical western Pacific during boreal summer

Paleofire, Vegetation, and Climate Reconstructions of the Middle to Late Holocene From Lacustrine Sediments of the Toushe Basin, Taiwan

Dominant Processes for Dependence of Boreal Summer Intraseasonal Oscillation on El Niño Phases

Contact Info

Product

Resources

About