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Explore in-depth analyses of North Pacific Oscillation, West Pacific Teleconnection Pattern, and East Asian Winter Monsoon. Discover the findings and implications for winter climate dynamics and monsoon transitions. Dive into the relationship between various atmospheric patterns and global warming effects. Uncover ancient climate reconstructions using tree-ring chronologies in Asia. Gain insights into factors influencing monsoon behavior and summer rainfall patterns in the Asian-Northwest Pacific region. Stay informed on significant regime shifts in temperature and precipitation over the past decades in East Asia and Taiwan.
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Summary R98229014 Kirsten Feng
The North Pacific Oscillation – West Pacific Teleconnection Pattern : Mature-Phase Structure and Winter Impacts MEGAN E. LINKIN AND SUMANT NIGAM
Introduction and conclusion • NPO / WP is a prominent mode of winter midlatitude variability consitituted by both the NPO and WP teleconnection pattern. • NPO / WP variability, on subseasonal time scales, is characterized by a large-scale meridional dipole in SLP and geopotential height.
NPO/WP is strongly linked to marginal ice zone variability of the Arctic seas with an influence that surpasses that of other Pacific modes. Although NPO/WP variability and impacts have not been as extensively analyzed as PNA or ENSO, it is shown to be more consequential for Arctic sea ice and North American winter hydroclimate.
Low-Frequency Variability of Surface Air Temperature in a 1000-Year Integration of a Coupled Atmosphere-Ocean-Land Surface Model SYUKURO MANABE AND RONALD J. STOUFFER
Introduction and conclusion • There are two models for the coupled model: • 1. Mixed layer model: the general circulation model of the atmosphere combined with a simple slab model of the mixed layer ocean • 2. Fixed SST model: the same atmosphere model overlying seasonally varying
The large abrupt events caused by thermohaline circulation fluctuation like Younger Dryas, didn’t occur in the model. • According to the paper, it doesn’t take the anthopologic activity into consideration, thus the warming impact didn’t appear also.
Both of the coupled model and the mixed layer model without ocean curents can approximately simulate the power spectrum of observed, global mean SAT at decadal to interdecadal timescales.
Impact of global warming on the East Asian winter monsoon revealed by nine coupled atmosphere-ocean GCMs Masatake E. Hori and Hiroki Ueda
Weakening of the EAWM accompanied by a strong anticyclonic anomaly over the North Pacific corresponding to a weakened and/or the northern shift of the Aleutian Low (AL). • The weakening of both the AL and the Siberian High (SH), which gives rise to a weakened pressure gradient along the eastern coast of the Eurasian continent.
Response of 850 hPa wind reveals an overall weakening of the EAWM. • Indices of the EAWM also shows a negative trend. • The EAWM response against global warming.
Global surface temperature signals in pine ring-width chronologies from southern monsoon Asia B. M. Buckley, B. I. Cook, A. Bhattacharyya, D. Dukpa, and V. Chaudhary
Decadal scale droughts over northwestern Thailand over the past 448 years: links to the tropical Pacific and Indian Ocean sectors Brendan M. Buckley A Kritsadapan Palakit
Both of these two papers are talking about how they did for reconstructing ancient climate by tree rings. • Those kind of trees (pine and teak) have significant growing patterns corresponding to climate. The main factor is the precipitation of the pre-monsoon period.
Each paper shows: • The tree ring is able to reflect the ENSO signal and the influence of the tropical oceans in controlling the moisture availability • The teak chronology is reliable to confirm that their record is a proxy for summer monsoon strength and/or duration, and highlight the importance of soil moisture availability in the seasons of transition.
Important Factors for the Development of the Asian–Northwest Pacific summer Monsoon HIROAKI UEDA, MASAMICHI OHBA, SHANG-PING XIE
A new method is developed to evaluate the effects of sea surface temperature (SST) and other changes on these rapid monsoon transitions. • The latter changes include solar radiation, land memory, and atmospheric transient (SLAT) effects. • Their model is tried to take those factors into calculation, then it can better simulate the robust rainfall during monsoon and mei-yu.
Both the correlation analyses and the composites indicate that in stronger EAWM years, the Siberian high and the higher-level subtropical westerly jet are stronger, and the Aleutian low and the East Asia trough are deeper. • Almost all the indices show that EAWM can also exert a remarkable leading effect on the summer monsoon in next year, including opposite precipitation patterns in different latitudes along the west pacific ocean.
The early 1950s regime shift in temperature in Taiwan and East Asia Tzu-Ting Lo And Huang-Hsiung Hsu
There is an abrupt change during the 1950s, especially in spring and summer proved by more than two statistics methods analyzing different dataset. • The regime shift pattern is more obvious on SST which may be related to PDO than precipitation.