scholarly journals Multi-scale variation of the meridional movement of the western Pacific warm pool and its associated large-scale climate features

2016 ◽  
Vol 129 (3-4) ◽  
pp. 859-872 ◽  
Author(s):  
Guojun Zhou ◽  
Song Yang ◽  
Dawei Zheng
Keyword(s):  
Large Scale ◽  
Warm Pool ◽  
Western Pacific ◽  
Western Pacific Warm Pool ◽  
Multi Scale ◽  
Pacific Warm Pool ◽  
The Western Pacific ◽  
Scale Variation

scholarly journals Strong Ocean–Atmosphere Interactions during a Short-Term Hot Event over the Western Pacific Warm Pool in Response to El Niño

2016 ◽  
Vol 29 (10) ◽  
pp. 3841-3865 ◽  
Author(s):  
Guixing Chen ◽  
Huiling Qin
Keyword(s):  
Convective Instability ◽  
Large Scale ◽  
Warm Pool ◽  
Western Pacific ◽  
Western Pacific Warm Pool ◽  
Short Term ◽  
Pacific Warm Pool ◽  
Ocean Atmosphere ◽  
The Western Pacific ◽  
Hot Event

Abstract A short-term hot event with a very high sea surface temperature (SST ≥ 30°C) occurred in the western Pacific warm pool during November 2006. The interactions between this ocean hot event, atmospheric convection, and large-scale dynamics are studied using satellite observations, buoy measurements, air–sea fluxes analysis, and global reanalysis. It is shown that SST variation and deep convection over the western Pacific behave like a remote response to the El Niño warm SST anomaly in the central Pacific that induces westward-moving atmospheric convection and equatorial waves. The large-scale subsidence associated with propagating convection not only promotes high SSTs in the western Pacific through establishing cloud-free conditions and increasing heat content in a thin ocean mixed layer, but also produces convective instability through capping substantial water vapor in the lower troposphere. Under the precondition of convective instability and the steering of tropical easterlies, some convective systems propagate coherently from the central to western Pacific and intensify. In particular, new cloud clusters are dynamically attracted to the warmest oceans with maximum atmospheric instability. The enhanced convective activity then transfers oceanic energy into the atmosphere, strengthens upper-ocean mixing, and returns the positive SST anomalies to more typical values. In such a coupled system, synoptic-scale convective activities at an interval of 5–8 days are selectively amplified and thus are filtered to an intraseasonal (20–30-day) oscillation, depending on the phase of the hot event over the western Pacific. The observed evidence has implications for the predictability of short-term climate, and it offers critical information for validating the coupled ocean–atmosphere dynamics in climate models.

Role of Abnormally Enhanced MJO over the Western Pacific in the Formation and Subseasonal Predictability of the Record-Breaking Northeast Asian Heatwave in the Summer of 2018

2020 ◽  
Vol 33 (8) ◽  
pp. 3333-3349 ◽  
Author(s):  
Pang-Chi Hsu ◽  
Yitian Qian ◽  
Yu Liu ◽  
Hiroyuki Murakami ◽  
Yingxia Gao
Keyword(s):  
Real Time ◽  
Time Scale ◽  
Wave Train ◽  
Northeast Asia ◽  
Warm Pool ◽  
Western Pacific ◽  
Western Pacific Warm Pool ◽  
Pacific Warm Pool ◽  
Northeast Asian ◽  
The Western Pacific

AbstractIn the summer of 2018, Northeast Asia experienced a heatwave event that broke the existing high-temperature records in several locations in Japan, the Korean Peninsula, and northeastern China. At the same time, an unusually strong Madden–Julian oscillation (MJO) was observed to stay over the western Pacific warm pool. Based on reanalysis diagnosis, numerical experiments, and assessments of real-time forecast data from two subseasonal-to-seasonal (S2S) models, we discovered the importance of the western Pacific MJO in the generation of this heatwave event, as well as its predictability at the subseasonal time scale. During the prolonged extreme heat period (11 July–14 August), a high pressure anomaly with variability at the intraseasonal (30–90 days) time scale appeared over Northeast Asia, causing persistent adiabatic heating and clear skies in this region. As shown in the composites of MJO-related convection and circulation anomalies, the occurrence of this 30–90-day high anomaly over Northeast Asia was linked with an anomalous wave train induced by tropical heating associated with the western tropical Pacific MJO. The impact of the MJO on the heatwave was further confirmed by sensitivity experiments with a coupled GCM. As the western Pacific MJO-related components were removed by nudging prognostic variables over the tropics toward their annual cycle and longer time scales (>90 days) in the coupled GCM, the anomalous wave train along the East Asian coast disappeared and the surface air temperature in Northeast Asia lowered. The MJO over the western Pacific warm pool also influenced the predictability of the extratropical heatwave. Our assessments of two S2S models’ real-time forecasts suggest that the extremity of this Northeast Asian heatwave can be better predicted 1–4 weeks in advance if the enhancement of MJO convection over the western Pacific warm pool is predicted well.

Coupled Mg/Ca and clumped isotope measurements at IODP Site U1488 confirm absence of Plio-Pleistocene sea surface temperature cooling in the Western Pacific Warm Pool

2020 ◽  
Author(s):  
Niklas Meinicke ◽  
Maria Reimi ◽  
Christina Ravelo ◽  
Nele Meckler
Keyword(s):  
Surface Temperature ◽  
Sea Surface Temperature ◽  
Planktonic Foraminifera ◽  
Warm Pool ◽  
Western Pacific ◽  
Sea Surface ◽  
Western Pacific Warm Pool ◽  
Pacific Warm Pool ◽  
The Western Pacific

<p>The Western Pacific Warm Pool (WPWP) as a major source of heat and water vapor has a crucial influence on climate dynamics both in the tropics and globally. Yet, there is conflicting proxy evidence regarding the evolution of WPWP temperatures since the Miocene. On the one hand TEX<sub>86</sub> data suggest a gradual cooling by ~2℃ (O’Brian et al., 2014, Zhang et al., 2014) from the Pliocene to today, while faunal (planktonic foraminifera) sea surface temperature estimates (Dowsett, 2007) and Mg/Ca data measured in planktonic foraminifera (Wara et al., 2005) on the other hand indicate the absence of any long-term temperature trends. It has been suggested that Mg/Ca temperatures could on these time scales be biased by long-term changes of the Mg/Ca ratio of seawater (Evans et al., 2016). To test the influence of the proposed seawater changes on Mg/Ca we combined data from two independent temperature proxies, Mg/Ca and clumped isotopes, measured on two species of planktonic foraminifera from IODP Site U1488 in the central WPWP. Our study finds good agreement between both proxies thereby verifying the validity of Mg/Ca records from the WPWP and confirming the absence of a Plio-Pleistocene cooling trend for the WPWP. This finding suggests that the persistent disagreement between foraminifer-based proxies such as Mg/Ca and biomarker data might be caused by different environmental parameters being recorded in the two archives.</p><p> </p><p>References:</p><p>O’Brien CL, Foster GL, Martínez-Botí MA, Abell R, Rae JWB, Pancost RD. High sea surface temperatures in tropical warm pools during the Pliocene. Nature Geoscience. 2014;7(8):606-11.</p><p>Zhang YG, Pagani M, Liu Z. A 12-million-year temperature history of the tropical Pacific Ocean. Science. 2014;344(6179):84-7.</p><p>Dowsett H. Faunal re-evaluation of Mid-Pliocene conditions in the western equatorial Pacific. Micropaleontology. 2007;53(6):447-56.</p><p>Wara MW, Ravelo AC, Delaney ML. Permanent El Nino-like conditions during the Pliocene warm period. Science. 2005;309(5735):758-61.</p><p>Evans D, Brierley C, Raymo ME, Erez J, Müller W. Planktic foraminifera shell chemistry response to seawater chemistry: Pliocene–Pleistocene seawater Mg/Ca, temperature and sea level change. Earth and Planetary Science Letters. 2016;438:139-48.</p>

Sign in / Sign up

Export Citation Format

Share Document