• <tr id="yyy80"></tr>
  • <sup id="yyy80"></sup>
  • <tfoot id="yyy80"><noscript id="yyy80"></noscript></tfoot>
  • 99热精品在线国产_美女午夜性视频免费_国产精品国产高清国产av_av欧美777_自拍偷自拍亚洲精品老妇_亚洲熟女精品中文字幕_www日本黄色视频网_国产精品野战在线观看 ?

    ENSO Frequency Asymmetry and the Pacific Decadal Oscillation in Observations and 19 CMIP5 Models

    2018-03-07 06:58:03RenpingLINFeiZHENGandXiaoDONG
    Advances in Atmospheric Sciences 2018年5期

    Renping LIN,Fei ZHENG?,2,and Xiao DONG

    1International Center for Climate and Environment Sciences,Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029,China

    2Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters,Nanjing University of Information Science and Technology,Nanjing 210044,China

    1.Introduction

    The El Ni?o–Southern Oscillation(ENSO),as the most important natural variation on the interannual timescale,exerts considerable impacts on global climate.Thus,for several decades,great attention has been paid to investigating the mechanisms of ENSO(Bjerknes,1969;Jin,1997;Wang and Picaut,2004).In recent years,the decadal modulations of ENSO have attracted significant attention(An and Wang,2000).Timmermann(2003)suggested a nonlinear mechanism that generates decadal ENSO amplitude modulations without invoking extratropical dynamics.Yeh et al.(2004)stated that the decadal modulation of ENSO is primarily due to atmospheric noise processes.

    The Pacific Decadal Oscillation(PDO)is a climate mode on the decadal timescale that can influence global and regional climate(Mantua et al.,1997;Newman et al.,2016).Yeh and Kirtman(2005)investigated the relationship between Pacific decadal variability and decadal ENSO amplitude modulation and found that the PDO is unrelated to the modulation of ENSO amplitude.However,others have argued that the decadal modulations of ENSO variability are related to decadal climate modes,such as the PDO(Kravtsov,2011).Besides,Feng et al.(2014)claimed that the PDO can impact the evolution of ENSO,e.g.,El Ni?o(EN)decays slowly(rapidly)during positive(negative)PDO phases.Verdon and Franks(2006)investigated the interaction between ENSO and the PDO using proxy climate records derived from paleoclimate data of the past 400 years.

    However,decadal modulation of ENSO frequency asymmetry has not been intensively studied.For example,are there more(fewer)EN events than La Ni?a(LN)events in positive(negative)PDO phases?In this study,using the output of 19 models from the Coupled Model Intercomparison Project Phase 5(CMIP5)experiments combined with observational data,we investigate the modulation of ENSO frequency asymmetry(EN and LN occurrence frequency)by the phases of the PDO.Specifically,the following two questions are addressed:(1)Is the frequency of EN and LN events modulated by different PDO phases?(2)If so,what is the reason for this decadal modulation?

    2.Data and methods

    The following datasets are used in this study:(1)monthly mean sea surface temperature data provided by the NOAA’s Extended Reconstructed SST dataset,version 3b(ERSST.v3b),with a horizontal resolution of2°×2°(Smith et al.,2008).This dataset is available from 1854 to the present day.(2)The Kalnay et al.(1996)NCEP–NCAR reanalysis(R1)dataset,with a resolution of 2.5°×2.5°and covering the period 1948–2014.(3)Global sea level pressure(SLP)data from the Second Hadley Centre SLP dataset(HadSLP2),with a resolution of 5°×5°(Allan and Ansell,2006).The period 1900–2014 is used to investigate the modulation of ENSO frequency asymmetry by the PDO.When the mechanism is examined,we use the circulation data from R1 over the period 1948–2014.

    Additionally,outputs from the pre-industrial runs of 19 CMIP5 models are analyzed to validate observational results(Taylor et al.,2012).Details of the CMIP5 models used in this study are listed in Table 1.The coupled models are freely integrated for several hundred years—much longer than the time span of the observational data.Thus,more robust conclusions can be drawn if the results derived from the ensemble mean of the models are consistent with those from observation.

    The commonly used Ni?o3.4 index associated with ENSO is defined as the area average of monthly SST anomalies in the region(5°N–5°S,170°–120°W)(Trenberth et al.,2002).The climatology is derived from the whole period of each dataset.The December–January–February(DJF)averaged Ni?o3.4 SST anomalies from the ERSST.v3b observations of 1900–2014 are shown in Fig.1a.The Ni?o3.4 index reveals substantial multi-decadal oscillations superimposed on interannual variability.Because our focus here is on the interannual variability of the Ni?o3.4 index,we apply a nineyear high-pass filter to the original Ni?o3.4 index,and obtain a new result for the Ni?o3.4 index without multi-decadal variability(Fig.1b).

    We select EN(LN)events by identifying years when the Ni?o3.4 SST index exceeds 1(is less than?1)standard deviation.Additionally,the an indexRis calculated to reveal the difference between EN and LN event occurrence:

    in whichNEN(NLN)denotes the number of EN(LN)events.R=0 means that the number of EN events is the same as the number of LN events.

    The monthly PDO index is defined as the time series of the leading empirical orthogonal function(EOF)of monthly mean SST anomalies for the Pacific Ocean north of 20°N in the observational data(Mantua et al.,1997;Wang et al.,2012).Before performing the EOF calculation,the global mean SST anomaly is firstly removed to reduce the influence of long-term trends.Here,we mainly concentrate on the decadal modulation by the PDO,as in Feng et al.(2014).Following Wang et al.(2012),the Pacific decadal variability considered in this study is the first two EOFs of monthly SST anomalies in the North Pacific: the PDO and the North Pacific Gyre Oscillation(NPGO).In the observational data,the first(second)EOF is defined as the PDO(NPGO)(Wang et al.,2012).In the CMIP5 models,we provide the pattern correlation coefficients(PCCs)between two EOF modes of CMIP5 models and the observed PDO mode and NPGO mode(Table 2).We define the mode of a model as the PDO mode when the PCC of that mode with the observed PDO(NPGO)mode is higher(lower).According to this criterion,the second mode of eight models(ACCESS1.0,BCC CSM1.1,CanESM2,CESM1(CAM5),CNRM-CM5,CSIRO Mk3.6.0,FGOALS-s2 and MRI-CGCM3)is defined as the PDO mode.The final PDO patterns are also shown in Fig.2.The November–March(NDJFM)average is regarded as the PDO index(Fig.1c).Following Feng et al.(2014),positive(negative)PDO years are identified when the PDO index is greater(less)than zero.Furthermore,to exclude years when the PDO index is rather neutral,we select a threshold of the PDO index as 0.2 standard deviations,rather than zero as in Feng et al.(2014).The black line in Fig.1c denotes 0.2 standard deviations of the PDO index.Actually,the main results are insensitive to our chosen threshold.When identifying the numbers of EN and LN events,positive(negative)PDO years are considered as warm(cold)phases in the following analysis.

    Table 1.Details of the pre-industrial control simulation experiments of the 19 CMIP5 models chosen in this study.

    Fig.1.Time series of(a)unfiltered and(b)nine-year high-pass filtered DJF Ni?o3.4 index,and(c)yearly PDO index,derived from ERSST.v3b during 1900 to 2014.The dashed line in(a)is the nine-year low-pass filtered Ni?o3.4 index.The black lines in(c)denote 0.2 standard deviations of the yearly PDO index.

    To test the significance of the modulation of ENSO frequency asymmetry by PDO phases,we use the Monte Carlo method(Chu and Wang,1997).In the 115 years of the observed time series(1900–2014),there are 45 positive PDO years.Thus,we choose 45 years randomly from the observed time series,one million times,to obtain one million samples.We then calculateRfor each sample.The probability distribution function(PDF)of the one millionRvalues is obtained.If the observedRis outside the 99%range of the PDF,we consider it to have reached the 99%level of significance according to the Monte Carlo test.The method is similar when the negative PDO phase is tested.

    Fig.2.PDO patterns of the(a)observational data and(b–t)simulations of 19 CMIP5 models(names given above each panel).In ACCESS1.0,BCCCSM1.1,CanESM2,CESM1(CAM5),CNRM-CM5,CSIRO Mk3.6.0,FGOALS-s2 and MRI-CGCM3,the PDO patterns are defined as the second EOF mode of the North Pacific SST anomalies.In the observational data and other models,the PDO patterns are defined as the first EOF mode of the North Pacific SST anomalies.

    Table 2.PCCs between the observed EOF1 mode and simulated EOF1 and EOF2 modes in 19 models.

    3.Results

    3.1.SST difference between positive and negative PDO phases

    Before examining the ENSO frequency asymmetry modulated by PDO phases,we firstly show the differences in SST,SLP and the wind field at 850 hPa between positive and negative PDO phases in Fig.3,in the observational data and in the multi-model simulations.The observational data show that the SLP difference between positive and negative PDO phases mainly occurs at midlatitudes.A notable negative anomaly occurs in the North Pacific,which is associated with the deepened Aleutian low in positive PDO phases.Additionally,although the PDO is defined as the leading empirical SST mode in the North Pacific,it has a considerable influence on the tropical Pacific.According to previous studies,this influence of the PDO on the tropics takes place via atmospheric teleconnections associated with the decadal background change(Barnett et al.,1999;Pierce et al.,2000;Wang and An,2002;Feng et al.,2014).In positive PDO phases,the eastern equatorial Pacific is anomalously warm.Similar conclusions have also been made by Feng et al.(2014)and Dong and Xue(2016).Additionally,compared to negative PDO phases,in positive PDO phases there are notable anomalous westerlies over the central equatorial Pacific.These PDO phase–dependent background westerly anomalies on the decadal timescale may be associated with the fact that more EN events tend to occur in positive PDO phases,although it is well known that westerly wind bursts are essential to triggering EN events(Lengaigne et al.,2004).

    Fig.3.(a)Observed and(b–t)simulated(model names given above each panel)differences in SST(color shading;units: °C),SLP(contours;units:hPa)and 850-hPa wind(vectors;units:m s?1)between positive and negative PDO phases.

    As for the simulation results,most models reproduce the negative SLP anomaly in the North Pacific,albeit with a slightly different location of the anomaly center.However,the magnitude of the SST anomaly—especially in the tropical eastern Pacific—is underestimated in most of the CMIP5 coupled models,which is associated with the weakly portrayed low-level westerly anomaly in the equatorial central Pacific.

    3.2.ENSO composition in positive and negative PDO phases

    To compare the EN/LN events between positive and negative PDO phases,we examine the spatial pattern of SST composition in EN/LN mature winter(DJF)in positive and negative PDO phases,separately(Fig.4).In positive PDO phases,in the observational data,with EN events the equatorial eastern Pacific is anomalously warm,and in the northern/southern central Pacific and equatorial western Pacific it is anomalously cool(Fig.4).The cooling anomaly in the northern and southern Pacific may be associated with the occurrence of a positive PDO phase,while that in the equatorial western Pacific may be associated with EN events(Shakun and Shaman,2009).Most models reproduce this spatial pattern of global SST,with respective regional bias( figure omitted).In negative PDO phases,with the positive SST anomaly in the central and eastern equatorial Pacific in EN events,the positive SST anomaly in the North Pacific is more significant than its South Pacific counterpart(Fig.4).Note that in positive PDO phases with EN events,the SST near the western coast of the American continent is anomalously warm;whereas,in negative PDO phases with EN events there is no significant signal.Besides,in the observational data,with EN events the positive SST anomaly in the equatorial eastern Pacific is much stronger in positive PDO phases than in negative PDO phases.Meanwhile,in the simulation results,models cannot reasonably reproduce this difference.That is,in the simulation results the contrast in magnitude between positive and negative PDO phase is negligible.

    Fig.4.Composite SST anomaly spatial pattern(color shading;units:°C)in(a,b)EN and(c,d)LN mature winter(DJF)in(a,c)positive(i.e.,warm)and(b,d)negative(i.e.,cool)PDO phases,based on the observational data(lefthand panels)and multi-model ensemble mean(right-hand panels).The oblique lines denote values that exceed the 95%confidence level in the observational results.

    With respect to LN events,the observational data in Fig.4c show that in positive PDO phases there are significantly negative SSTs in the equatorial central and eastern Pacific and central and western North Pacific.Meanwhile,a positive SST anomaly is located in most regions of the Pacific Ocean.The magnitude of the negative SST anomaly in the central and eastern equatorial Pacific in the multi-model ensemble of the CMIP5 models is stronger than that in the observational data.Besides,not all of the CMIP5 models reproduce the concurrent negative SST anomaly in both the northern and equatorial Pacific in positive-PDO-phase LN events.Even in those models that do,the location of the negative SST anomaly in the northern Pacific is considerablely biased compared to the observed location.Thus,as stated in previous studies,it is still a difficult task to simulate the connection between the PDO and ENSO,or between the midlatitudes and equatorial ocean(Newman et al.,2016).In negative PDO phases with LN events,the observed positive SST anomaly in the North Pacific shifts eastward compared to in positive phases,and a South Pacific counterpart exists(Fig.4d).Most of the CMIP5 models reproduce the horseshoe pattern in the Pacific reasonably.The main deviation of the models is the overly westward shifted cold tongue in the equatorial Pacific,which is an unresolved problem in the current CMIP5 models.In addition,the negative SST anomaly in the equatorial Pacific is much stronger in negative PDO phases than in positive PDO phases.As mentioned for the EN events,in the simulation results,models cannot reproduce this difference reasonably.The contrast in magnitude between positive and negative PDO phases in the simulation results is negligible.

    Figure 5 shows the SST difference between positive and negative PDO phases in EN/LN events,separately.The results for EN and LN events are similar,i.e.,a negative(positive)center in the western and central North Pacific(equatorial central and eastern Pacific and coastline of the American continent).The multi-model ensemble reproduces the negative center in the North Pacific with only a slight location bias.However,the SST difference in the equatorial Pacific is rather weak.This indicates that many climate models suf-fer from bias in simulating the connection between the PDO and ENSO,or between the midlatitudes and equatorial ocean(Newman et al.,2016).

    Fig.5.Composite spatial pattern of SST anomaly differences(color shading;units:°C)in(a)EN and(b)LN events between different PDO phases[positive(i.e.,warm)minus negative(i.e.,cool)],based on the observational data(left-hand panels)and multi-model ensemble mean(right-hand panels).

    3.3.ENSO frequency asymmetry in different PDO phases

    Next,we investigate the PDO phase–dependent ENSO frequency asymmetry using the method defined in section 2.As shown in Fig.6,results show that in positive(negative)PDO phasesRis positive(negative),indicating that EN is more frequent than LN in positive PDO phases,while LN is more frequent than EN in negative PDO phases.In the observational data,EN is 300%more(58%less)frequent than LN in positive(negative)PDO phases.That is,positive(negative)PDO phases are conducive to the occurrence of more EN(LN)events.Besides,the amplitude ofRis also asymmetric in positive and negative PDO phases.For instance,in positive PDO phases EN is 300%more frequent than LN,which is much larger than its counterpart in negative PDO phases(58%).We also drew the above figure with unfiltered Ni?o3.4 index values,and the results were almost the same( figure not shown).

    To test the significance of our results,we apply the Monte Carlo significant test to the observational data.The PDF ofRin positive and negative PDO phases is shown in Fig.7.In positive(negative)PDO phases,the observedRvalue is positive(negative),which means that in positive(negative)PDO phases EN is more(less)frequent than LN.The same conclusion can be drawn from Fig.6.Besides,from Fig.7 it can be seen that the observedRvalue(red line)is beyond the threshold in both positive and negative PDO phases,indicating that our above conclusion,i.e.,that EN is more(less)frequent than LN in positive(negative)PDO phases,is significant at the 99%confidence level.The PDF distributions of the CMIP5 models are shown in Fig.8.Most of the CMIP5 model results are consistent with the observational results.However,there are six(seven)models that cannot reproduce the significant PDO phase–dependent ENSO asymmetry in positive(negative)PDO phases.This conclusion can also be drawn from Fig.6.

    Fig.6.The R values(percentage difference between the number of EN and LN events relative to the number of LN events)based on the observational data(OBS),multi-model ensemble(MME),and 19 CMIP5 models.The letter“Y”indicates that the R value is statistically significant at the 1%level.The vertical line(orange)denotes one standard deviation for the 19 model results.

    Fig.7.PDF of R in(a)positive and(b)negative phases of the PDO in the Monte Carlo test with a sample size of 1 000 000.The red line denotes the observed value of R and the blue line denotes the threshold[99%percentile for(a)and 1%percentile for(b)]beyond which the observed R can be regarded as significant.

    Fig.8.PDF of R derived from the observational data(OBS)and 19 CMIP5 models in(a)positive and(b)negative phases of the PDO in the Monte Carlo test with a sample size of 1 000 000.The red line denotes the value of R and the blue line denotes the threshold(99%percentile)beyond which R can be regarded as significant.

    Fig.8.(Continued)

    3.4.Discussion on the relationship between the PDO and ENSO

    To examine the possible causes of the ENSO frequency asymmetry between positive and negative PDO phases,the differences in SST,SLP and the wind field at 850 hPa between positive and negative PDO phases can be referred to,as mentioned in subsection 3.1(Fig.3).It can be seen that,although the PDO is defined as the leading empirical SST mode in the North Pacific,it has a considerable influence on the tropical Pacific.In positive PDO phases,the eastern equatorial Pacific is anomalously warm.Additionally,compared to negative PDO phases,in positive PDO phases there are notable anomalous westerlies over the central equatorial Pacific.This PDO-dependent westerly anomaly over the central equatorial Pacific on the decadal timescale may be with the fact that more EN rather than LN events tend to occur in positive PDO phases.However,it should be acknowledged that,from the evidence shown here, one cannot say for certain that it is the PDO that results in the occurrence of more EN events.Notably,previous studies(e.g.,Newman et al.2003)argue that the PDO is an ENSO-forced signal.In this paper,using observational data and CMIP5 coupled model results,we only reveal the phenomenon that there tend to be more EN events in positive PDO phases.Of course,two possibilities exist,i.e.,that the PDO influences ENSO or vice versa.More work(e.g.,numerical sensitivity experiments)should be carried out to explore the mechanisms involved(i.e.,whether the PDO influences ENSO,or the other way around).

    4.Conclusions and discussion

    This study examines the modulation of ENSO frequency asymmetry by the different phases of the PDO.Results from observational data show that more EN(LN)events tend to occur in positive(negative)PDO phases.Specifically,EN is 300%more(58%less)frequent than LN in positive(negative)PDO phases.Monte Carlo testing is used to check the significance of the above observational evidence,and the results show that the conclusion,i.e.,that EN is more(less)frequent than LN in positive(negative)PDO phases,is statistically significant at the 99%confidence level.Besides the observational evidence,the pre-industrial simulations of 19 CMIP5 models are analyzed using the same method as with the observed data.We find that most of the CMIP5 models exhibit the same results as observed in both positive and negative PDO phases,indicating that ENSO frequency asymmetry is indeed modulated by the PDO phases.

    The modulation of ENSO frequency asymmetry by the PDO may be due to the background SST and circulation patterns in different PDO phases.In positive PDO phases there are notable anomalous westerlies over the central equatorial Pacific,which are associated with the warming SST east of the anomalous low-level wind.Thus,this decadal-scale westerly wind anomaly associated with positive PDO phases may encourage more EN events,rather than LN events,to occur.However,in previous studies(e.g.,Newman et al.,2003)it has been argued that the PDO is an ENSO-forced signal.Of course,two possibilities exist—that the PDO influences ENSO or vice versa.In this paper,using observational data and CMIP5 coupled model results,we only seek to reveal the phenomenon that there tend to be more EN events in positive PDO phases,and in doing so we find that this relationship between the PDO and ENSO is statistically significant based on the Monte Carlo test.

    Besides analysis of observational data and CMIP5 multimodel pre-industrial control simulations,sensitivity experiments using numerical models are necessary to fully explore the modulation of ENSO frequency asymmetry by the different PDO phases.Such work has recently begun using a coupled climate model with assimilated SST in the ocean component(Dong et al.,2016).Indeed,it has already been found that this method can reproduce the decadal variation of the East Asian summer monsoon reasonably well(Lin et al.,2016).Thus,further study using model experiments to investigate the associated mechanisms is warranted.

    Acknowledgements.We appreciate the suggestions and comments from the two anonymous reviewers and the Editor,which helped to improve the quality of the original paper.This work was jointly supported by the National Key R&D Program of China(Grant No.2017YFA0604201),the National Natural Science Foundation of China(Grant Nos.41576019,41606027 and 41706028),and the China Postdoctoral Science Foundation(Grant No.2015M571095).

    Allan,R.,and T.Ansell,2006:A new globally complete monthly historical gridded mean sea level pressure dataset(HadSLP2):1850-2004.J.Climate,19,5816–5842,https://doi.org/10.1175/JCLI3937.1.

    An,S.I.,and B.Wang,2000:Interdecadal change of the structure of the ENSO mode and its impact on the ENSO frequency.J.Climate,13,2044–2055,https://doi.org/10.1175/1520-0442(2000)013<2044:ICOTSO>2.0.CO;2.

    Barnett,T.P.,D.W.Pierce,M.Latif,D.Dommenget,and R.Saravanan,1999:Interdecadal interactions between the tropics and midlatitudes in the Pacific basin.Geophys.Res.Lett.,26,615–618,https://doi.org/doi:10.1029/1999GL900042.

    Bjerknes,J.,1969:Atmospheric teleconnections from the equatorial Pacific.Mon.Wea.Rev.,97(3),163–172,https://doi.org/10.1175/1520-0493(1969)097<0163:ATFTEP>2.3.CO;2.

    Chu,P.S.,and J.X.Wang,1997:Tropical cyclone occurrences in the vicinity of Hawaii:Are the differences between El Ni?o and non-El Ni?o years significant?J.Climate,10(10),2683–2689,https://doi.org/10.1175/1520-0442(1997)010<2683:TCOITV>2.0.CO;2.

    Dong,X.,and F.Xue,2016:Phase transition of the Pacific decadal oscillation and decadal variation of the East Asian summer monsoon in the 20th century.Adv.Atmos.Sci.,33(3),330–338,https://doi.org/doi:10.1007/s00376-015-5130-7.

    Dong,X.,R.P.Lin,J.Zhu,and Z.T.Lu,2016:Evaluation of ocean data assimilation in CAS-ESM-C:Constraining the SST field.Adv.Atmos.Sci.,33(7),795–807,https://doi.org/10.1007/s00376-016-5234-8.

    Feng,J.,L.Wang,and W.Chen,2014:How does the East Asian summer monsoon behave in the decaying phase of El Ni?o during different PDO phases?J.Climate,27,2682–2698,https://doi.org/10.1175/JCLI-D-13-00015.1.

    Jin,F.F.,1997: An equatorial ocean recharge paradigm for ENSO.Part I:Conceptual model.J.Atmos.Sci.,54(7),811–829,https://doi.org/10.1175/1520-0469(1997)054<0811:AEORPF>2.0.CO;2.

    Kalnay,E.,and Coauthors,1996: The NCEP/NCAR 40-year reanalysis project.Bull.Amer.Meteor.Soc.,77(3),437–472,https://doi.org/10.1175/1520-0477(1996)077<0437:TNYRP>2.0.CO;2.

    Kravtsov,S.,2011:An empirical model of decadal ENSO variability.Climate Dyn.,39(9–10),2377–2391,https://doi.org/10.1007/s00382-012-1424-y.

    Lengaigne,M.,E.Guilyardi,J.P.Boulanger,C.Menkes,P.Delecluse,P.Inness,J.Cole,and J.Slingo,2004:Triggering of El Ni?no by westerly wind events in a coupled general circulation model.Climate Dyn.,23(6),601–620,https://doi.org/10.1007/s00382-004-0457-2.

    Lin,R.,J.Zhu,and F.Zheng,2016:Decadal shifts of East Asian summer monsoon in a climate model free of explicit GHGs and aerosols.Scientific Reports,6,38546,https://doi.org/10.1038/srep38546.

    Mantua,N.J.,S.R.Hare,Y.Zhang,J.M.Wallace,and R.C.Francis,1997:A Pacific interdecadal climate oscillation with impacts on salmon production.Bull.Amer.Meteor.Soc.,78,1069–1079,https://doi.org/10.1175/1520-0477(1997)078<1069:APICOW>2.0.CO;2.

    Newman,M.,and Coauthors,2016:The Pacific decadal oscillation,revisited.J.Climate,29(12),4399–4427,https://doi.org/10.1175/JCLI-D-15-0508.1.

    Pierce,D.W.,T.P.Barnett,and M.Latif,2000:Connections between the Pacific Ocean tropics and midlatitudes on decadal time scales.J.Climate,13,1173–1194.

    Shakun,J.D.,and J.Shaman,2009:Tropical origins of North and South Pacific decadal variability.Geophys.Res.Lett.,36,L19711,https://doi.org/10.doi:1029/2009GL040313.

    Smith,T.M.,R.W.Reynolds,T.C.Peterson,and J.Lawrimore,2008:Improvements to NOAA’s historical merged land–ocean surface temperature analysis(1880-2006).J.Climate,21,2283–2296,https://doi.org/10.1175/2007JCLI2100.1.

    Taylor,K.E.,R.J.Stouffer,and G.A.Meehl,2012:An overview of CMIP5 and the experiment design.Bull.Amer.Meteor.Soc.,93,485–498,https://doi.org/10.1175/BAMS-D-11-00094.1.

    Timmermann,A.,2003:Decadal ENSO amplitude modulations:A nonlinear paradigm.Global and Planetary Change,37(1–2),135–156,https://doi.org/10.1016/S0921-8181(02)00194-7.

    Trenberth,K.E.,J.M.Caron,D.P.Stepaniak,and S.Worley,2002:Evolution of El Ni?o–Southern Oscillation and global atmospheric surface temperatures.J.Geophys.Res.,107,4065,https://doi.org/doi:10.1029/2000JD000298.

    Verdon,D.C.,and S.W.Franks,2006:Long-term behaviour of ENSO:interactions with the PDO over the past 400 years inferred from paleoclimate records.Geophys.Res.Lett.,33(6),L06712,https://doi.org/10.1029/2005GL025052.

    Wang,B.,and S.I.An,2002:A mechanism for decadal changes of ENSO behavior:Roles of background wind changes.Climate Dyn.,18,475–486,https://doi.org/10.1007/s00382-001-0189-5.

    Wang,C.Z.,and J.Picaut,2004:Understanding ENSO physics—a review.Earth’s Climate:The Ocean-Atmosphere Interaction,C.Wang et al.,Eds.,American Geophysical Union,21–48,https://doi.org/10.1029/147GM02.

    Wang,H.,A.Kumar,W.Q.Wang,and Y.Xue,2012:Influence of ENSO on Pacific decadal variability:An analysis based on the NCEP climate forecast system.J.Climate,25,6136–6151,https://doi.org/10.1175/JCLI-D-11-00573.1.

    Yeh,S.W.,and B.P.Kirtman,2005:Pacific decadal variability and decadal ENSO amplitude modulation.Geophys.Res.Lett.,32(5),L05703,https://doi.org/10.1029/2004GL021731.

    Yeh,S.W.,J.G.Jhun,I.S.Kang,and B.P.Kirtman,2004:The decadal ENSO variability in a hybrid coupled model.J.Climate,17(6),1225–1238,https://doi.org/10.1175/1520-0442(2004)017<1225:TDEVIA>2.0.CO;2.

    成熟少妇高潮喷水视频| 中文字幕人成人乱码亚洲影| 久久午夜福利片| 97人妻精品一区二区三区麻豆| 在线a可以看的网站| 亚洲欧美日韩高清在线视频| 中出人妻视频一区二区| www.999成人在线观看| 欧美日本亚洲视频在线播放| 国产高清视频在线播放一区| 国产老妇女一区| 免费av观看视频| 好看av亚洲va欧美ⅴa在| 看十八女毛片水多多多| 免费av不卡在线播放| 亚洲专区中文字幕在线| 国产精品,欧美在线| 成人特级av手机在线观看| 在线观看午夜福利视频| 欧美成人免费av一区二区三区| 国产色爽女视频免费观看| 757午夜福利合集在线观看| 91字幕亚洲| 日本精品一区二区三区蜜桃| 亚洲精华国产精华精| 51国产日韩欧美| 国产精品永久免费网站| 欧美+日韩+精品| 国产高潮美女av| 九九久久精品国产亚洲av麻豆| 欧美性猛交╳xxx乱大交人| 美女cb高潮喷水在线观看| 如何舔出高潮| 成人高潮视频无遮挡免费网站| 国内精品美女久久久久久| 国产av在哪里看| 男女做爰动态图高潮gif福利片| 最近视频中文字幕2019在线8| 十八禁人妻一区二区| 蜜桃亚洲精品一区二区三区| 国产亚洲精品综合一区在线观看| 老熟妇仑乱视频hdxx| 日本与韩国留学比较| 色吧在线观看| 桃红色精品国产亚洲av| 老师上课跳d突然被开到最大视频 久久午夜综合久久蜜桃 | 99久久九九国产精品国产免费| 大型黄色视频在线免费观看| 久久中文看片网| 国内毛片毛片毛片毛片毛片| bbb黄色大片| 中文字幕人妻熟人妻熟丝袜美| 91九色精品人成在线观看| 国产精品久久久久久久电影| 97超视频在线观看视频| 欧美成狂野欧美在线观看| 在线播放国产精品三级| 欧美不卡视频在线免费观看| 国产一区二区在线观看日韩| 成人特级av手机在线观看| 亚洲欧美日韩卡通动漫| 人妻久久中文字幕网| 91狼人影院| 日韩欧美国产一区二区入口| 九色成人免费人妻av| 久久久色成人| 成人一区二区视频在线观看| 每晚都被弄得嗷嗷叫到高潮| 成人特级av手机在线观看| 可以在线观看的亚洲视频| 国产色婷婷99| 老熟妇仑乱视频hdxx| 天堂√8在线中文| 美女cb高潮喷水在线观看| 亚洲天堂国产精品一区在线| 亚洲中文字幕日韩| 国产国拍精品亚洲av在线观看| 午夜福利视频1000在线观看| 99精品在免费线老司机午夜| 国产三级中文精品| 我要搜黄色片| 久久精品国产亚洲av天美| 国产白丝娇喘喷水9色精品| eeuss影院久久| 午夜亚洲福利在线播放| 亚洲avbb在线观看| 人妻制服诱惑在线中文字幕| 亚洲综合色惰| 国产欧美日韩一区二区精品| 色综合婷婷激情| 国产精品影院久久| 天美传媒精品一区二区| 欧美高清性xxxxhd video| 老熟妇乱子伦视频在线观看| 欧美午夜高清在线| 精品一区二区三区视频在线| 亚洲午夜理论影院| 精品久久久久久久久亚洲 | 久久99热6这里只有精品| 国产精品人妻久久久久久| 日韩欧美国产一区二区入口| 一区二区三区四区激情视频 | 久久精品夜夜夜夜夜久久蜜豆| 嫩草影院新地址| 夜夜夜夜夜久久久久| 好看av亚洲va欧美ⅴa在| 国产午夜精品久久久久久一区二区三区 | 中文字幕免费在线视频6| 有码 亚洲区| 日本 欧美在线| 51国产日韩欧美| 中文在线观看免费www的网站| 91在线观看av| 日本黄色视频三级网站网址| 久久人人精品亚洲av| 色吧在线观看| 日韩欧美免费精品| 午夜福利视频1000在线观看| 久久久国产成人精品二区| 国产在线精品亚洲第一网站| 国产伦在线观看视频一区| 亚洲第一区二区三区不卡| 精品人妻视频免费看| 亚洲av免费在线观看| 69av精品久久久久久| 国产日本99.免费观看| av黄色大香蕉| 欧美潮喷喷水| 亚洲av五月六月丁香网| 婷婷亚洲欧美| 人妻制服诱惑在线中文字幕| 一进一出抽搐gif免费好疼| 日韩中字成人| 国产精品日韩av在线免费观看| 午夜老司机福利剧场| 欧美丝袜亚洲另类 | 精品国内亚洲2022精品成人| 人妻制服诱惑在线中文字幕| 此物有八面人人有两片| 欧美黄色片欧美黄色片| 99国产精品一区二区蜜桃av| 中文字幕精品亚洲无线码一区| 高清在线国产一区| 伊人久久精品亚洲午夜| 免费电影在线观看免费观看| 国内精品久久久久久久电影| 亚洲av五月六月丁香网| 国产三级黄色录像| 欧美极品一区二区三区四区| 国内精品美女久久久久久| 90打野战视频偷拍视频| 99热这里只有精品一区| 欧美一区二区精品小视频在线| 我要看日韩黄色一级片| 亚洲男人的天堂狠狠| 全区人妻精品视频| 18禁在线播放成人免费| 蜜桃亚洲精品一区二区三区| 亚洲一区二区三区色噜噜| 琪琪午夜伦伦电影理论片6080| 美女高潮的动态| 精品福利观看| 国产一区二区激情短视频| 18禁黄网站禁片午夜丰满| 乱码一卡2卡4卡精品| 欧美不卡视频在线免费观看| 两性午夜刺激爽爽歪歪视频在线观看| 一本久久中文字幕| 男女视频在线观看网站免费| 一夜夜www| 嫩草影院新地址| 能在线免费观看的黄片| 久久伊人香网站| 国产 一区 欧美 日韩| 欧美另类亚洲清纯唯美| 怎么达到女性高潮| 又爽又黄a免费视频| 中文资源天堂在线| 成年女人看的毛片在线观看| 成人三级黄色视频| 国产一区二区亚洲精品在线观看| 久久久久国内视频| 校园春色视频在线观看| 丁香六月欧美| 亚洲经典国产精华液单 | 一区二区三区免费毛片| 欧美极品一区二区三区四区| 成人高潮视频无遮挡免费网站| 免费看a级黄色片| 深夜精品福利| 丝袜美腿在线中文| bbb黄色大片| 国产国拍精品亚洲av在线观看| 男女床上黄色一级片免费看| 久久亚洲真实| 人妻久久中文字幕网| 赤兔流量卡办理| 成人av一区二区三区在线看| 宅男免费午夜| 久久亚洲真实| 夜夜夜夜夜久久久久| 看免费av毛片| 欧美日韩瑟瑟在线播放| 又粗又爽又猛毛片免费看| 十八禁网站免费在线| 亚洲精品久久国产高清桃花| 中出人妻视频一区二区| 中文资源天堂在线| 亚洲第一区二区三区不卡| 亚洲精品日韩av片在线观看| 99在线人妻在线中文字幕| 日本a在线网址| 亚洲五月天丁香| 国产69精品久久久久777片| 小蜜桃在线观看免费完整版高清| 欧美一区二区精品小视频在线| 88av欧美| 男人的好看免费观看在线视频| 别揉我奶头 嗯啊视频| 午夜两性在线视频| 两个人视频免费观看高清| 亚洲欧美日韩高清在线视频| 一进一出抽搐gif免费好疼| 最近中文字幕高清免费大全6 | 久久草成人影院| 精品一区二区三区视频在线观看免费| 99国产精品一区二区蜜桃av| netflix在线观看网站| 男女做爰动态图高潮gif福利片| 日韩有码中文字幕| 欧美日韩综合久久久久久 | 男女之事视频高清在线观看| 精品久久久久久久人妻蜜臀av| 最新中文字幕久久久久| 国内精品久久久久久久电影| 人妻夜夜爽99麻豆av| 男女之事视频高清在线观看| 日日夜夜操网爽| eeuss影院久久| 国产人妻一区二区三区在| 日本熟妇午夜| 噜噜噜噜噜久久久久久91| 日韩欧美国产在线观看| 亚洲成人中文字幕在线播放| 老司机午夜十八禁免费视频| 99视频精品全部免费 在线| 深爱激情五月婷婷| 国产综合懂色| 久久这里只有精品中国| 欧美黄色淫秽网站| 欧美+亚洲+日韩+国产| 国产精品三级大全| 99久国产av精品| 国内精品美女久久久久久| 欧美精品国产亚洲| aaaaa片日本免费| 国产黄片美女视频| 日韩欧美免费精品| 人人妻人人看人人澡| 亚洲av.av天堂| 亚洲精品456在线播放app | 成年女人永久免费观看视频| 国产大屁股一区二区在线视频| av在线观看视频网站免费| 久久九九热精品免费| 日韩精品中文字幕看吧| 国产精品女同一区二区软件 | 99久久久亚洲精品蜜臀av| 欧美zozozo另类| 小蜜桃在线观看免费完整版高清| АⅤ资源中文在线天堂| 久久人妻av系列| 日韩成人在线观看一区二区三区| 老司机午夜十八禁免费视频| 91字幕亚洲| 男插女下体视频免费在线播放| 老司机深夜福利视频在线观看| 一二三四社区在线视频社区8| 老司机福利观看| 婷婷精品国产亚洲av在线| 亚洲av免费高清在线观看| 成人国产综合亚洲| 天美传媒精品一区二区| 日韩欧美在线乱码| 欧美一区二区国产精品久久精品| 亚洲欧美日韩高清在线视频| 97超视频在线观看视频| 国产大屁股一区二区在线视频| 婷婷色综合大香蕉| 成人鲁丝片一二三区免费| 国内少妇人妻偷人精品xxx网站| 精品久久久久久久末码| 亚洲国产日韩欧美精品在线观看| АⅤ资源中文在线天堂| 亚洲在线观看片| 久久99热这里只有精品18| 桃色一区二区三区在线观看| 人人妻,人人澡人人爽秒播| 一区二区三区免费毛片| 亚洲人成网站高清观看| 国产精品久久久久久亚洲av鲁大| 九色成人免费人妻av| 三级毛片av免费| 熟妇人妻久久中文字幕3abv| 亚洲真实伦在线观看| 国产精品日韩av在线免费观看| 亚洲五月婷婷丁香| 高潮久久久久久久久久久不卡| 亚洲av成人不卡在线观看播放网| 日韩欧美免费精品| 老司机午夜十八禁免费视频| 午夜日韩欧美国产| avwww免费| 久久性视频一级片| 国产熟女xx| 国产69精品久久久久777片| 老熟妇乱子伦视频在线观看| 岛国在线免费视频观看| 在线十欧美十亚洲十日本专区| 欧美日韩中文字幕国产精品一区二区三区| 国产欧美日韩精品一区二区| 哪里可以看免费的av片| 国产成人a区在线观看| 久久99热这里只有精品18| 精品午夜福利视频在线观看一区| 18禁黄网站禁片免费观看直播| 日韩 亚洲 欧美在线| 成年女人看的毛片在线观看| 久久九九热精品免费| 在线a可以看的网站| 亚洲av第一区精品v没综合| 小蜜桃在线观看免费完整版高清| a级毛片免费高清观看在线播放| 久久久久久久亚洲中文字幕 | 精品国内亚洲2022精品成人| 国产黄a三级三级三级人| 亚洲人成网站高清观看| 天堂动漫精品| 99热精品在线国产| 国产国拍精品亚洲av在线观看| 十八禁国产超污无遮挡网站| 国产精品免费一区二区三区在线| 尤物成人国产欧美一区二区三区| 99久久精品热视频| 日本在线视频免费播放| 色噜噜av男人的天堂激情| 成年女人毛片免费观看观看9| 婷婷精品国产亚洲av在线| 18禁黄网站禁片午夜丰满| 日韩欧美 国产精品| 国产精华一区二区三区| 国内精品美女久久久久久| 国产精华一区二区三区| 亚洲中文字幕一区二区三区有码在线看| 99riav亚洲国产免费| av天堂中文字幕网| 久久久久九九精品影院| 国产极品精品免费视频能看的| 十八禁人妻一区二区| 欧美最新免费一区二区三区 | 亚洲,欧美,日韩| 国产一区二区三区在线臀色熟女| 在线播放无遮挡| 久久精品综合一区二区三区| 丁香六月欧美| 亚洲最大成人av| 日韩欧美在线乱码| 免费大片18禁| 国产精品乱码一区二三区的特点| 91久久精品国产一区二区成人| 欧美激情久久久久久爽电影| 免费搜索国产男女视频| 精品不卡国产一区二区三区| 一边摸一边抽搐一进一小说| 精品一区二区三区视频在线观看免费| 欧美日韩福利视频一区二区| 国产亚洲精品综合一区在线观看| 一级毛片久久久久久久久女| 少妇熟女aⅴ在线视频| 亚洲av一区综合| 亚洲,欧美,日韩| 观看美女的网站| 欧美+日韩+精品| 日本免费a在线| 在线观看舔阴道视频| 国产精品精品国产色婷婷| 久久久久久久久中文| 女生性感内裤真人,穿戴方法视频| 免费人成在线观看视频色| 国产精品一区二区三区四区久久| 免费人成在线观看视频色| 亚洲精品粉嫩美女一区| 人人妻人人看人人澡| 舔av片在线| 91狼人影院| 天美传媒精品一区二区| 网址你懂的国产日韩在线| 精品久久久久久久末码| 亚洲精品在线美女| 亚洲成人久久爱视频| 国产精品综合久久久久久久免费| 亚洲人成伊人成综合网2020| 日本与韩国留学比较| 欧美中文日本在线观看视频| 3wmmmm亚洲av在线观看| 精品久久久久久久久久久久久| 精品一区二区免费观看| 午夜精品一区二区三区免费看| 欧美精品国产亚洲| 午夜日韩欧美国产| 一夜夜www| 伦理电影大哥的女人| 精品久久久久久久末码| 永久网站在线| 可以在线观看的亚洲视频| 久久久久亚洲av毛片大全| 久久久久性生活片| 欧美在线黄色| 中文在线观看免费www的网站| 美女高潮喷水抽搐中文字幕| 国产精品电影一区二区三区| 露出奶头的视频| 麻豆一二三区av精品| 色综合站精品国产| 欧美日本视频| 精品久久国产蜜桃| 国产精品一区二区免费欧美| 亚洲欧美日韩高清专用| 天堂av国产一区二区熟女人妻| 琪琪午夜伦伦电影理论片6080| 欧美高清成人免费视频www| 免费大片18禁| 波野结衣二区三区在线| 亚洲最大成人手机在线| 国产爱豆传媒在线观看| 欧美3d第一页| 国产蜜桃级精品一区二区三区| 国产精品一区二区免费欧美| 欧美性猛交黑人性爽| 国产伦在线观看视频一区| 女人十人毛片免费观看3o分钟| 在线观看66精品国产| 亚洲av免费高清在线观看| 中文字幕av成人在线电影| 桃色一区二区三区在线观看| 精品国产三级普通话版| 成人美女网站在线观看视频| 噜噜噜噜噜久久久久久91| 国产探花极品一区二区| 国产精品久久久久久人妻精品电影| av福利片在线观看| 午夜精品久久久久久毛片777| 欧美又色又爽又黄视频| 久久精品国产99精品国产亚洲性色| 男女下面进入的视频免费午夜| 一本精品99久久精品77| 琪琪午夜伦伦电影理论片6080| 亚洲一区二区三区不卡视频| 欧美成人a在线观看| 国产极品精品免费视频能看的| 欧美xxxx性猛交bbbb| 免费看a级黄色片| 亚洲avbb在线观看| 丰满人妻一区二区三区视频av| 日日摸夜夜添夜夜添小说| 国产精品精品国产色婷婷| 成人国产综合亚洲| 午夜精品在线福利| 人人妻人人澡欧美一区二区| 别揉我奶头 嗯啊视频| 亚洲熟妇中文字幕五十中出| 欧美日韩国产亚洲二区| 国产精品久久久久久人妻精品电影| 国产精品久久久久久久电影| 国产麻豆成人av免费视频| 成人三级黄色视频| 老师上课跳d突然被开到最大视频 久久午夜综合久久蜜桃 | 久久草成人影院| 亚洲综合色惰| 看片在线看免费视频| 欧美性猛交╳xxx乱大交人| 免费无遮挡裸体视频| 男人的好看免费观看在线视频| 中文字幕av成人在线电影| 中出人妻视频一区二区| 一进一出抽搐gif免费好疼| 麻豆av噜噜一区二区三区| 九九久久精品国产亚洲av麻豆| 国产精品一区二区免费欧美| 最近视频中文字幕2019在线8| 欧美不卡视频在线免费观看| 麻豆国产av国片精品| 人人妻人人澡欧美一区二区| www.熟女人妻精品国产| 亚洲国产欧美人成| 国产精品野战在线观看| 亚洲国产欧美人成| 免费一级毛片在线播放高清视频| 黄片小视频在线播放| 亚洲精品乱码久久久v下载方式| 国内少妇人妻偷人精品xxx网站| av视频在线观看入口| 国产伦在线观看视频一区| 一级毛片久久久久久久久女| 久久久久免费精品人妻一区二区| 亚洲av日韩精品久久久久久密| 观看免费一级毛片| 久久亚洲精品不卡| 国产v大片淫在线免费观看| 国产精品久久久久久亚洲av鲁大| 三级毛片av免费| 成人国产一区最新在线观看| 精品人妻熟女av久视频| 国产高潮美女av| 一级作爱视频免费观看| 悠悠久久av| 成人性生交大片免费视频hd| 国内少妇人妻偷人精品xxx网站| 能在线免费观看的黄片| 精品人妻偷拍中文字幕| 麻豆国产av国片精品| 12—13女人毛片做爰片一| 久9热在线精品视频| av在线蜜桃| 国产精品美女特级片免费视频播放器| 亚洲成人久久性| 日韩有码中文字幕| 日韩人妻高清精品专区| 51国产日韩欧美| 午夜福利在线在线| 亚洲欧美激情综合另类| 少妇人妻一区二区三区视频| 久久国产精品人妻蜜桃| 黄色视频,在线免费观看| 女同久久另类99精品国产91| 亚洲精品久久国产高清桃花| 国产av在哪里看| 亚洲天堂国产精品一区在线| 亚洲av日韩精品久久久久久密| 国产黄片美女视频| 热99re8久久精品国产| 久久精品国产亚洲av香蕉五月| 欧美最黄视频在线播放免费| 欧美成人性av电影在线观看| 成人毛片a级毛片在线播放| 欧美极品一区二区三区四区| 国产三级黄色录像| 免费无遮挡裸体视频| 国产美女午夜福利| 婷婷六月久久综合丁香| 18+在线观看网站| 一区二区三区免费毛片| 日本五十路高清| 精品人妻一区二区三区麻豆 | 一区二区三区高清视频在线| 国产单亲对白刺激| 十八禁网站免费在线| 人妻制服诱惑在线中文字幕| 成人性生交大片免费视频hd| 搡女人真爽免费视频火全软件 | 国产成人aa在线观看| 国产主播在线观看一区二区| 色综合婷婷激情| 18禁裸乳无遮挡免费网站照片| 午夜免费成人在线视频| 国产色爽女视频免费观看| 国产黄色小视频在线观看| 1000部很黄的大片| 国产精品久久电影中文字幕| 九九热线精品视视频播放| 黄色日韩在线| 欧美日韩福利视频一区二区| 久久人人精品亚洲av| 校园春色视频在线观看| av欧美777| 久久这里只有精品中国| 亚洲国产精品成人综合色| 国产熟女xx| 俄罗斯特黄特色一大片| 亚洲av五月六月丁香网| 日本一二三区视频观看| 国产高潮美女av| 亚洲成a人片在线一区二区| 亚洲成人中文字幕在线播放| 日本在线视频免费播放| 男女床上黄色一级片免费看| 免费一级毛片在线播放高清视频| 俄罗斯特黄特色一大片| 激情在线观看视频在线高清| 亚洲欧美清纯卡通| 国产精品综合久久久久久久免费| 99热这里只有是精品在线观看 | 欧美黑人巨大hd| 亚洲成人免费电影在线观看| 99精品久久久久人妻精品| 好男人电影高清在线观看| 精品日产1卡2卡| www.999成人在线观看| 国产黄片美女视频| 桃色一区二区三区在线观看| 亚洲国产欧洲综合997久久,| 亚洲av五月六月丁香网| 99热这里只有是精品在线观看 | 欧美绝顶高潮抽搐喷水| 午夜免费激情av| 亚洲av成人不卡在线观看播放网| 人妻久久中文字幕网| 亚洲av日韩精品久久久久久密| 久久香蕉精品热| 国产精品伦人一区二区| 亚洲内射少妇av| 亚洲人成网站在线播放欧美日韩| 91麻豆av在线| 国产精品爽爽va在线观看网站| 国产白丝娇喘喷水9色精品|