Simulation of East Asian Summer Monsoon (EASM) in SP‐CCSM4: Part I—Seasonal mean state and intraseasonal variability

Yan, Jin; Stan, Cristiana

doi:10.1002/2015jd024035

Cited by 9 publications

(8 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In all simulations isolines of mean rainfall are too zonal and mean rainfall is as much as twice the observed amount in large parts of China. These biases are hardly affected by resolution or coupling, consistent with previous studies (Song and Zhou, 2014a;Jiang et al, 2016;Johnson et al, 2016;Ogata et al, 2017). The spatial pattern of IPV matches observations better than mean precipitation.…”

Section: Mean State Biasessupporting

confidence: 90%

“…Jiang et al (2016), analyzing CMIP3-CMIP5 simulations at horizontal resolutions of ∼ 60-620 km, and Chen and Frauenfeld (2014), analyzing CMIP5 simulations at horizontal resolutions of ∼ 210-830 km, obtained a similar result for coupled GCMs. In MetUM GA3 summer rainfall biases inside the Asian monsoon domain at 50-180 • E, 20 • S-40 • N (Johnson et al, 2016) and the East Asian monsoon domain at 120-180 • E, 0-40 • N (Ogata et al, 2017) increasingly worsen when changing resolution from N96 (135 km at 50 • N) to N216 (60 km) and N216 to N512 (25 km).…”

Section: Introductionmentioning

confidence: 98%

“…We can attribute some of the skill at simulating variability to the reasonable simulation of the oscillatory dynamic flow. Large biases in mean precipitation are very likely imposed by physical parameterizations, e.g., the use of a convective parameterization, which has previously been shown to affect the simulation of summer rainfall variability over China (e.g., Chen et al, 2010;DeMott et al, 2013;Jin and Stan, 2016).…”

mentioning

confidence: 99%

See 2 more Smart Citations

Intraseasonal summer rainfall variability over China in the MetUM GA6 and GC2 configurations

et al. 2018

View full text Add to dashboard Cite

Abstract. The simulation of intraseasonal precipitation variability over China in extended summer (May–October) is evaluated based on six climate simulations of the Met Office Unified Model. Two simulations use the Global Atmosphere 6.0 (GA6) and four the Global Coupled 2.0 (GC2) configuration. Model biases are large such that mean precipitation and intraseasonal variability reach twice their observed values, particularly in southern China. To test the impact of air–sea coupling and horizontal resolution, GA6 and GC2 at horizontal resolutions corresponding to ∼25, 60, and 135 km at 50∘ N are analyzed. Increasing the horizontal resolution and adding air–sea coupling have little effect on these biases. Pre-monsoon rainfall in the Yangtze River basin is too strong in all simulations. Simulated rainfall amounts in June are too high along the southern coast and persist in the coastal region through July, with only a weak northward progression. The observed northward propagation of the Meiyu–Baiu–Changma rainband from spring to late summer is poor in all GA6 and GC2 simulations. To assess how well the MetUM simulates spatial patterns of temporally coherent precipitation, empirical orthogonal teleconnection (EOT) analysis is applied to pentad-mean precipitation. Patterns are connected to large-scale processes by regressing atmospheric fields onto the EOT pentad time series. Most observed patterns of intraseasonal rainfall variability are found in all simulations, including the associated observed mechanisms. This suggests that GA6 and GC2 may provide useful predictions of summer intraseasonal variability despite their substantial biases in mean precipitation and overall intraseasonal variance.

show abstract

Section: Mean State Biasessupporting

confidence: 90%

Section: Introductionmentioning

confidence: 98%

mentioning

confidence: 99%

See 1 more Smart Citation

Intraseasonal summer rainfall variability over China in the MetUM GA6 and GC2 configurations

et al. 2018

View full text Add to dashboard Cite

show abstract

“…1b, 6a). This is probably due to the lack of air-sea interaction over the western Pacific warm pool (Wang et al 2005;Kim and Hong 2010;Song and Zhou 2014;Jin and Stan 2016). When treating the PCC of 0.5 between the observed and the simulated anomalies of the stream function over the domain (30 -80°N, 60°W -150°E) as a threshold, 6 out of the 10 members can better reproduce the anomalies of circulation in July 2018.…”

Section: B Agcm Resultsmentioning

confidence: 99%

Record-Breaking Northward Shift of the Western North Pacific Subtropical High in July 2018

Liu

Zhu

et al. 2019

Journal of the Meteorological Society of Japan

View full text Add to dashboard Cite

The northward shift of the Western North Pacific Subtropical High (WNPSH) in July 2018 broke the historical record since 1958 and resulted in extreme heat waves and casualties across Northeast Asia (NEA). In the present work, we associated this extreme WNPSH anomaly with the anomalies of barotropic anticyclone above NEA originating from the strongest positive tripole pattern of sea surface temperature anomaly (SSTA) in the North Atlantic in July. Both data analysis and numerical experiments indicated that the positive tripole SSTA pattern could produce an upper-tropospheric wave source over Europe, which stimulated an eastward propagating wave train along the subpolar westerly jet over the Eurasian Continent. When its anticyclonic node reached NEA, the WNPSH started to shift northward. After the cyclonic node in the circulation anomaly encountered the Tibetan Plateau (TP), atmospheric diabatic heating was enhanced over the eastern TP, initiating another subtropical wave train, which furthered the northward shift of the WNPSH. Therefore, the wave source over Europe was critical for the northward shift of the WNPSH in July, connecting the tripole SSTA pattern in the North Atlantic with the WNPSH anomaly and maintaining the downstream effects of thermal forcing over the eastern TP on the East Asian summer monsoon.

show abstract

“…Using a 5-level spectrum AGCM, Huang et al (2001) concluded that the Kuo scheme (Kuo, 1965) performs better in simulating the East Asian summer monsoon (EASM) precipitation, compared to the Manabe (Manabe and Strickler, 1964) and Arakawa-Schubert schemes (Arakawa and Schubert, 1974). Besides the direct modification on the convection schemes, the super-parameterization approach (Grabowski, 2001;Khairoutdinov and Randall, 2001), which embeds an explicit two-dimensional cloud-resolving model (CRM; e.g., Guichard and Couvreux, 2017 and the references therein), is incorporated into the climate system models (CSMs) and AGCMs to improve simulation of the EASM (Jin and Stan, 2016) and propagation of the boreal summer intraseasonal oscillation (DeMott et al, 2013).…”

mentioning

confidence: 99%

Effects of a stochastic multicloud parameterization on the simulated Asian‐Australian monsoon rainfall in an AGCM

Jiang

Cao

2019

Intl Journal of Climatology

View full text Add to dashboard Cite

The Asian‐Australian monsoon (AAM) plays a vital role in modulating the global and local climates. Current numerical models, including climate system models (CSMs) and atmospheric general circulation models (AGCMs), have difficulties in capturing the fundamental and intrinsic features of the AAM. By applying the stochastic multicloud model (SMCM) to the state‐of‐the‐art ECHAM6.3 atm model, we investigated the impacts of SMCM on the simulation of AAM precipitation. Though the modified model with the SMCM improves simulations of the AAM precipitation in June–July–August–September season, the solstice mode, the AAM domain, and the AAM precipitation intensity, deficiencies also exist in other aspects, that is, simulations of rainfall in December–January–February–March and April–May seasons, and the equinox mode. Analyses also unravelled the modified model improves in simulating the spatial patterns of seasonal variation of precipitation in the Indian monsoon region, western North Pacific monsoon region, and Australian monsoon region in terms of pattern correlation coefficient and normalized root‐mean square error scores. The enhanced simulation of solar radiation in the modified model favours improving the performance of the simulated solstice mode. In addition, moisture budget analysis was applied to investigate physical processes that modulate the variations and distributions of AAM precipitation. Analyses revealed that variations and distributions of the vertical integral of moisture flux convergence is closely associated with changes in precipitation, while the stratification of vertical moist transport is associated with changes in precipitation over land in the AAM region. In addition, the modified model influences the AAM precipitation mainly through the variations of moisture flux convergence. The present work potentially provides a method to improve the simulated capability of AGCMs.

show abstract

Simulation of East Asian Summer Monsoon (EASM) in SP‐CCSM4: Part I—Seasonal mean state and intraseasonal variability

Cited by 9 publications

References 46 publications

Intraseasonal summer rainfall variability over China in the MetUM GA6 and GC2 configurations

Intraseasonal summer rainfall variability over China in the MetUM GA6 and GC2 configurations

Record-Breaking Northward Shift of the Western North Pacific Subtropical High in July 2018

Effects of a stochastic multicloud parameterization on the simulated Asian‐Australian monsoon rainfall in an AGCM

Contact Info

Product

Resources

About