• <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 ?

    Distinct Evolution of the SST Anomalies in the Far Eastern Pacific between the 1997/98 and 2015/16 Extreme El Ni?os

    2022-04-02 05:29:34ShaoleiTANGJingJiaLUOLinCHENandYongqiangYU
    Advances in Atmospheric Sciences 2022年6期

    Shaolei TANG, Jing-Jia LUO*, Lin CHEN, and Yongqiang YU

    1Institute for Climate and Application Research (ICAR), Nanjing University of Information Science and Technology, Nanjing 210044, China

    2Key Laboratory of Meteorological Disaster, Ministry of Education (KLME)/ILCEC/CIC-FEMD, Nanjing University of Information Science and Technology, Nanjing 210044, China

    3State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics (LASG),Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China

    4University of Chinese Academy of Sciences, Beijing 100049, China

    5Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China

    ABSTRACT The 2015/16 El Ni?o displayed a distinct feature in the SST anomalies over the far eastern Pacific (FEP) compared to the 1997/98 extreme case. In contrast to the strong warm SST anomalies in the FEP in the 1997/98 event, the FEP warm SST anomalies in the 2015/16 El Ni?o were modest and accompanied by strong southeasterly wind anomalies in the southeastern Pacific. Exploring possible underlying causes of this distinct difference in the FEP may improve understanding of the diversity of extreme El Ni?os. Here, we employ observational analyses and numerical model experiments to tackle this issue. Mixed-layer heat budget analysis suggests that compared to the 1997/98 event, the modest FEP SST warming in the 2015/16 event was closely related to strong vertical upwelling, strong westward current, and enhanced surface evaporation, which were caused by the strong southeasterly wind anomalies in the southeastern Pacific.The strong southeasterly wind anomalies were initially triggered by the combined effects of warm SST anomalies in the equatorial central and eastern Pacific (CEP) and cold SST anomalies in the southeastern subtropical Pacific in the antecedent winter, and then sustained by the warm SST anomalies over the northeastern subtropical Pacific and CEP. In contrast, southeasterly wind anomalies in the 1997/98 El Ni?o were partly restrained by strong anomalously negative sea level pressure and northwesterlies in the northeast flank of the related anomalous cyclone in the subtropical South Pacific.In addition, the strong southeasterly wind and modest SST anomalies in the 2015/16 El Ni?o may also have been partly related to decadal climate variability.

    Key words: El N?o-Southern Oscillation, extreme El Ni?o, El Ni?o diversity, far eastern Pacific, decadal climate variability

    1. Introduction

    The El Ni?o-Southern Oscillation (ENSO) is the Earth’s most prominent driver for interannual climate variability, as highlighted by the occurrence of the latest extreme El Ni?o event in 2015/16 (Blunden and Arndt, 2016; Santoso et al.,2017). The pronounced global impacts of ENSO extend to social stability, food security, and marine habitats (e.g.,Glantz, 2001; Iizumi et al., 2014; Barnard et al., 2015; Hardiman et al., 2018), thus underscoring the necessity to improve understanding of ENSO dynamics for its accurate prediction and disaster risk reduction.

    As the first extreme El Ni?o of the 21st century, the 2015/16 El Ni?o is characteristically distinct from the 1997/98 extreme El Ni?o during its peak phase in November-January (Fig. 1; L’Heureux et al., 2017; Paek et al.,2017; Ren et al., 2017; Xue and Kumar, 2017; Zhong et al.,2019). For example, compared with the 1997/98 El Ni?o,the equatorial Pacific SST anomalies of the 2015/16 El Ni?o were cooler in the east and slightly warmer in the west, i.e., the equatorial warm SST anomaly center was displaced westward (Figs. 1a-c). Interestingly, the largest difference in the SST anomalies between the two extreme El Ni?os appeared in the far eastern Pacific (FEP, 0°-15°S,80°-100°W, red box in Fig. 1c), rather than in the equatorial Ni?o-3.4 region (5°N-5°S, 120°-170°W, blue box in Fig. 1c). As shown in Fig. 1d, the SST anomalies averaged in the Ni?o-3.4 region were nearly equal during the peak phase of the two extreme El Ni?os. In contrast, the SST anomalies in the FEP in the 1997/98 El Ni?o reached as high as 3.2°C, while those in the 2015/16 El Ni?o were merely 1.5°C, just a half of those in the 1997/98 El Ni?o.

    Fig. 1. Spatial pattern of SST anomalies (°C) during the mature phase (November-January, NDJ) of (a) the 1997/98 El Ni?o, (b) the 2015/16 El Ni?o, and (c) their difference. (d) SST anomalies averaged in the Ni?o-3.4 and fareastern Pacific (FEP) regions during the development of the 1997/98 and 2015/16 El Ni?os. Red and blue boxes in(c) denote the FEP (0°-15°S, 80°-100°W) and Ni?o-3.4 (5°N-5°S, 120°-170°W) regions, respectively. 0, -1, and+1 in the abscissa of (d) indicate the El Ni?o year, the preceding year, and the following year, respectively.

    Strong warm SST anomalies in the FEP often have significant impacts on the marine ecosystem in the eastern Pacific and economics and social stability of countries located along the west coast of South America (Barber and Chavez, 1983; Takahashi, 2004; Peng et al., 2019; Echevin et al., 2020). The Pacific coast of Peru and Ecuador is usually kept cool and dry by intense upwelling of cold water from subsurface. Strong warm events are often associated with deepening of the nearshore thermocline and nutricline(Barber and Chavez, 1983; Espinoza-Morriberon et al.,2017), and the upwelling of cold, nutrient-replete waters and the associated primary productivity are thus strongly depressed, leading to a modification of marine food chains and biodiversity (Barber and Chavez, 1983; Echevin et al.,2020). Furthermore, warm SST anomalies over the FEP tend to induce atmospheric deep convection, triggering heavy rainfall and flooding in the arid coastal zone. For example, during the 1997/98 El Ni?o event, the losses of the society and economy caused by devastating rainfall events in Northern Peru were estimated to exceed $3.5 million (Sanabria et al., 2018). Therefore, it is necessary to investigate the underlying mechanisms responsible for the large difference in the FEP SST anomalies between the two extreme events for better predictions and mitigations.

    Previous studies on the 2015/16 El Ni?o event have mainly focused on the westward displaced warm SST anomaly center along the equator compared to the 1997/98 El Ni?o event (e.g., L’Heureux et al., 2017; Paek et al., 2017;Ren et al., 2017; Xue and Kumar, 2017; Zhong et al., 2019).It has been suggested that this might be related to enhanced easterly wind anomalies in the eastern Pacific, which may have been partly caused by the multi-decadal enhancing of trade winds since 2000 (Luo et al., 2012; L’Heureux et al.,2017; Xue and Kumar, 2017) or strong equatorward winds(Zhong et al., 2019). In contrast, few studies have paid attention to possible causes of the large difference of SST anomalies in the FEP between the 1997/98 and 2015/16 extreme El Ni?os. Zhong et al. (2019) suggested that the suppressed SST anomaly in the Ni?o-1+2 region (0°-10°S, 80°-90°W)in 2015 might be related to the southerly wind anomalies over the southeastern tropical Pacific, which in turn were initially triggered by the warm SST anomalies over the northeastern subtropical Pacific (NESP, 15°-30°N, 110°-140°W, red box in Fig. 2b) in 2015 boreal spring. However, considerable cold SST anomalies existed in the southeastern subtropical Pacific (SESP, 20°-30°S, 70°-120°W, blue box in Fig.2b) since early 2015 (Figs. 2b, e). Whether the cold SESP SST anomalies might also have played a role in inducing the southeasterly wind anomalies, thus contributing to the suppressed SST development in the FEP in 2015, has not yet been explored. It remains unclear whether other processes besides SST changes might have played a role in the wind anomaly changes or not. Therefore, in this study, we attempt to explore these issues based on observational analyses and numerical experiments.

    Fig. 2. Spatial distributions of SST (shading, °C), surface wind (vector, m s-1), and rainfall (contour, CI: ±2.0, ±5.0, ±9.0, ±14.0 mm d-1) anomalies during the development [October(-1) to September(0)] of the 1997/98 El Ni?o (left column), the 2015/16 El Ni?o (middle column), and their differences (right column). Red and blue boxes in (b) denote the northeastern subtropical Pacific region (NESP, 15°-30°N, 110°-140°W) and southeastern subtropical Pacific region (SESP, 20°-30°S, 70°-120°W),respectively.

    The paper is organized as follows. The dataset, methodology, and model experiments are described in section 2. Section 3 compares the observed SST, precipitation, and wind anomalies between the 1997/98 and 2015/16 El Ni?o events. Section 4 investigates the possible factors that induce the southeasterly wind anomalies in the southeastern Pacific. Finally, a summary and discussion are given in section 5.

    2. Data, methodology, and numerical experiment

    2.1. Data and methodology

    The observational SST data used in this study are from the Hadley Centre Global Sea Ice and Sea Surface Temperature (HadISST) version 1.1 (Rayner et al., 2003). NCEP GODAS data provides oceanic 3D temperature and velocity fields (Saha et al., 2006). 20°C-isotherm depth is calculated using the EN4 dataset, a subsurface temperature and salinity dataset for the global oceans from the Met Office Hadley Centre (Good et al., 2013). Surface heat flux is analyzed using the ESSO-INCOIS TropFlux data (Kumar et al.,2012). Precipitation data is from the CPC Merged Analysis of Precipitation (CMAP, Xie and Arkin, 1997). To reduce the uncertainty of surface wind data, they are derived from the ensemble mean of the 10-m wind of the NCEP-DOE Reanalysis-2 data (Kanamitsu et al., 2002) and the JRA-55 reanalysis data (Kobayashi et al., 2015). Cloud amount data is from the International Satellite Cloud Climatology Project (ISCCP)-H Series (Young et al., 2018). Monthly anomalies are obtained by subtracting the monthly mean climatology of the period 1981-2010.

    The mixed-layer heat budget analysis is conducted to diagnose the relative importance of different processes in controlling changes in upper ocean temperatures during the developing phase of El Ni?o events. The mixed-layer temperature tendency equation may be written as:

    where u, v, and w denote three-dimensional ocean current velocities, T is the mixed-layer temperature, ()′denotes the interannual anomaly,denotes the monthly climatological mean, Qnetrepresents surface net heat fluxes (positive indicates ocean gains heat), R represents the residual term, ρ =103kg m-3is the density of water, cp= 4000 J kg-1K-1is the specific heat of water, and h is the mixed-layer depth that is defined as the depth where ocean temperature is 0.8°C lower than SST. All the budget terms in Eq. (1) are integrated from the surface to the mixed-layer base.

    2.2. Model description and experiment design

    2.2.1. The model

    The global ocean-atmosphere coupled model used in this study is the Climate Forecast System version 1.0 of Nanjing University of Information Science and Technology(NUIST CFS1.0), which is developed from the coupled model SINTEX-F (Luo et al., 2003, 2005a, b; Masson et al.,2005). The atmosphere component is the latest version of ECHAM4 with a high horizontal resolution of about 1.1° ×1.1° (T106) and a hybrid sigma-pressure vertical coordinate(19 levels in total). The ocean component is the reference version 8.2 of OPA with the ORCA 2 configuration, and the horizontal resolution is 2° cos (latitude) × 2° in longitude with meridional resolution being increased to 0.5° near the equator. It has 31 vertical levels, 19 of which are set in the top 400 meters. The coupling variables (i.e., SST, surface momentum, heat and water fluxes) are interpolated and exchanged every two hours between the OPA and ECHAM4 models by means of the OASIS 2.4 coupler (Valcke et al., 2000). The impact of ocean surface currents on the surface momentum flux is included (Luo et al., 2005b).The coupled model does not apply any flux correction except that sea ice cover is relaxed toward observed monthly climatology in the ocean model.

    2.2.2. Sensitivity experiments

    The NUIST CFS1.0 coupled model has displayed excellent performance in simulating and predicting El Ni?o/La Ni?a events (e.g., Luo et al., 2005a, 2008, 2017; Ham et al.,2019). Specifically, the model predicted an El Ni?o event occurring in the winter season of 2015 from as early as February 2015 (i.e., about 10 months in advance). The realtime ensemble forecasts of El Ni?o/La Ni?a using the NUIST CFS1.0 model at lead times of up to two years have been provided monthly at https://icar.nuist.edu.cn/qhcp/list.htm.

    The hindcast sensitivity experiments consist of ninemember ensemble predictions generated by various combinations of different initial conditions and modified coupling physics (Luo et al., 2005a, 2008). Only the observed weekly NOAA OISST values are assimilated into the coupled model to generate realistic and well-balanced initial conditions required for the hindcasts. To assess the possible impacts of negative SST anomalies in the SESP, positive SST anomalies in the NESP, and their combined impact on the development of SST anomalies in the FEP during the 2015/16 El Ni?o, six groups of sensitivity experiments are conducted.

    The first group of sensitivity experiments are started from 1 February 2015. The observed monthly climatological mean SSTs from 1981-2010 are specified in one sensitivity experiment (CLMFeb_SESP) and the observed monthly SST values from 2015 are specified in the other sensitivity experiment (OBSFeb_SESP) in the SESP, respectively. Elsewhere, free ocean-atmosphere coupling is kept in the two sensitivity experiments. Thus, the differences between the two sensitivity experiments (OBSFeb_SESPminus-CLMFeb_SESP) represent the impacts of the SESP SST anomalies on the development of FEP SST anomalies in the 2015/16 El Ni?o. The second group of sensitivity experiments is similar to the first group, except that the experiments are conducted starting from 1 March 2015. The differences between the two sensitivity experiments(OBSMar_SESP-minus-CLMMar_SESP) also represent the impacts of the SESP SST anomalies on the development of FEP SST anomalies in the 2015/16 El Ni?o. The results of the two groups of the sensitivity experiments that include 18 ensemble members in total (OBS_SESP-minus-CLM_SESP) are analyzed together to obtain robust results.

    Similarly, the third and fourth groups of sensitivity experiments are conducted to investigate the impact of SST anomalies in the NESP on the FEP SST anomalies (OBS_NESPminus-CLM_NESP). The fifth and sixth groups of sensitivity experiments are conducted to investigate the combined impact of SST anomalies in the NESP and SESP on the FEP SST anomalies (OBS_BOTH-minus-CLM_BOTH). These groups of the sensitivity experiments are summarized in Table 1.

    Table 1. Six groups of sensitivity experiments conducted to investigate possible impacts of SST anomalies in the southeastern subtropical Pacific (SESP, 20°-30°S, 70°-120°W), northeastern subtropical Pacific (NESP, 15°-30°N, 110°-140°W), and their combined impact on the development of SST anomalies during the 2015/16 El Ni?o.

    3. Comparison between the 1997/98 and 2015/16 extreme El Ni?os

    Figure 1 shows that in both 1997 and 2015, along with the development of basin-scale El Ni?o events, warm SST anomalies appeared in the FEP at the same time. However,the growth rates of SST anomalies in the FEP in the two extreme El Ni?o events were significantly different. As shown in Fig. 1d, the magnitudes of the warm SST anomalies in the FEP in the two events were nearly the same in April and both reached about 0.5°C. However, the FEP SST anomalies by September in 1997 reached more than 3.0°C,while those in 2015 were lower than 2.0°C.

    To explore possible underlying mechanisms behind thelarge difference in the FEP SST anomalies between the two extreme events, spatial patterns of SST, precipitation, and surface wind anomalies are compared. Figure 2 shows that remarkable differences existed in the surface wind anomalies over the southeastern Pacific (0°-30°S, 70°-120°W)between the two events. Strong southeasterly wind anomalies existed in the southeastern Pacific during the developing phase of the 2015/16 event (April-September). In contrast, there were no apparent southeasterly wind anomalies in the southeastern Pacific in the 1997/98 El Ni?o. These southeasterly wind anomalies in the 2015/16 event even crossed the equator and reached the North Pacific. Corresponding to the strong southeasterly wind anomalies, the 2015/16 event shows relatively strong westward propagating zonal current and upward vertical currents in the FEP compared to the 1997/98 event (Figs. 3b-c).

    It is worth mentioning that although the anomalous surface meridional winds in the 2015/16 event are always positive over the FEP, the anomalous zonal currents are not always flowing westward and vertical currents are not always upward [Figs. 3b-c, S1-S2 in the electronic supplementary material (ESM)]. This is probably because the zonal and vertical current anomalies in the FEP are not only affected by surface wind anomalies, but also affected by other factors, such as mesoscale eddies (Chaigneau et al.,2011), south equatorial current, and local-scale currents.The effect of meridional wind anomalies may be overwhelmed by other factors in 2015/16, resulting in the mismatch between southerly wind anomalies and eastward propagating zonal currents and downward vertical currents.This is the same case for the 1997/98 event. Nevertheless,of particular interest in this study is the difference between the 1997/98 and 2015/16 events. The difference in surface wind anomalies between the two events corresponds well with that in the current anomalies between the two events,with stronger southeasterly anomalies and westward propagating zonal currents and upward vertical currents in the 2015/16 event compared to the 1997/98 event, as shown in Fig. 3 and Figs. S1-S2 in the ESM.

    Fig. 3. (a) Meridional wind (m s-1), (b) vertical velocity (10-6 m s-1; positive indicates upwelling), (c) zonal current(m s-1), and (d) meridional current (m s-1) anomalies averaged in the FEP region (0°-15°S, 80°-100°W) during the developing phase [April(0) to September(0)] of the 1997/98 and 2015/16 El Ni?os.

    To investigate the relative contributions of different processes to the growth of the SST anomaly in the FEP in the two extreme events, mixed-layer heat budgets for the deve loping phase (April-September) of the two El Ni?os were analyzed. As shown in Fig. 4, thermocline feedback, Ekman pumping feedback, and zonal advection feedbackwere the three most important positive feedbacks for the development of SST anomalies in the FEP in the two extreme events. But all three terms were weaker in the 2015/16 El Ni?o than in the 1997/98 El Ni?o.

    Compared to the 1997/98 El Ni?o, the weaker thermocline feedback (- wˉ?T′/?z) in the 2015/16 El Ni?o is due to the relatively weak positive 20°C isotherm depth (D20)anomalies in the FEP (Fig. S3); the D20 anomalies are used to depict thermocline changes. The weaker Ekman pumping feedback (- w′/?z) and zonal advection feedback(- u′/?x) are related to the relatively strong westward propagating zonal current and upward vertical currents in the 2015/16 event (Fig. 3), which in turn are caused by the strong southeasterly anomalies in the southeastern Pacific(Fig. 2).

    Besides, the nonlinear process ( -v′?T′/?y) also has a positive impact on the development of SST anomalies in the FEP in the two events and contributes to the differences between the two events, which may be caused by both the larger -v′(Fig. 3d) and ?T′/?y (Fig. S4 in the ESM) in the 1997/98 event than those in the 2015/16 event. In contrast,the nonlinear process (-u′?T′/?x) has a negative impact on the development of SST anomalies in the two events and offsets the differences between the two events to a large extent,which may be caused by both the larger -u′(Fig. 3c) and?T′/?x (Fig. S5) in the 1997/98 event. This indicates that nonlinear ocean dynamic processes should be taken into consideration when investigate mechanisms and effects of El Ni?o events (e.g., An and Kim, 2017; Hayashi et al., 2020).

    Fig. 4. Mixed-layer heat budget analysis (°C month-1) for the developing phase (April-September) of the 1997/98 El Ni?o (blue), 2015/16 El Ni?o (red), and their difference (green) in the FEP (0°-15°S, 80°-100°W).

    Fig. 5. Surface net heat flux (Net) anomalies and its four components: latent heat flux (LH), shortwave radiation(SW), longwave radiation (LW), and sensible heat flux (SH) (W m-2; positive downward) averaged in the FEP(0°-15°S, 80°-100°W) during the developing phase [April(0) to September(0)] of the 1997/98 and 2015/16 El Ni?os.

    The results shown in Fig. 4 also suggest that, apart from the differences in the ocean dynamic processes, thermodynamic processes in the 2015/16 event might have also played a larger negative role in the development of the warm SST anomalies in the FEP. The surface net heat flux in the 2015/16 event was largely negative (i.e., ocean loses heat) and dominated by the latent heat flux (Fig. 5a). In contrast, the negative latent heat flux in the 1997/98 event was relatively small, and more importantly, its damping effect was mostly counteracted by the strong downward shortwave heat flux (Fig. 5b). Therefore, the negative surface net heat flux in the 1997/98 event was very weak and had a negligible impact on the development of the warm SST anomalies in the FEP in 1997 (Fig. 4). The strong downward shortwave heat flux in the 1997/98 event might have been caused by the positive SST-low cloud feedback (e.g., Klein et al.,2017); that is, the strong warm SST anomalies could have reduced the stratocumulus cloud fraction in the FEP (Fig.S6) and thus increased the shortwave heat flux into ocean(Fig. 5b).

    Note that in addition to the FEP, greatly reduced lowlevel cloud anomalies also existed in the Northern Hemisphere (NH) off-equator in August-September 1997, as compared to those in 2015 (Fig. S6g in the ESM). However, this does not mean that more shortwave radiation was able to enter and heat the ocean. That is because more positive precipitation anomalies occurred there (Figs. 2p-r). The total cloud amount anomalies in the NH off-equator in August-September 1997 are positive (Fig. S7), and at the same time, the middle- and high-level cloud amount anomalies are positive and are larger than those in 2015 (Fig. S8).The greater quantity of convective clouds at middle and high levels in the NH off-equator is in accordance with the larger positive precipitation anomalies there. This indicates that in the NH off-equator, positive SST anomalies play an active role by forcing the overlying atmosphere and inducing positive precipitation anomalies there. In contrast, positive SST anomalies in the FEP play a passive role and are partly strengthened by more shortwave radiation that is caused by reduced low-level cloud cover.

    4. Possible causes of the strong southeasterly wind anomalies in 2015

    4.1. Effects of SST anomalies on the southeasterly wind anomalies

    As was described above, different from the 1997/98 El Ni?o, the 2015/16 event experienced strong cross-equatorial southeasterly wind anomalies in the southeastern Pacific as early as in the antecedent autumn season (recall Figs. 2b, e). Accompanied with the strong southeasterly wind anomalies, positive SST anomalies existed in the NESP and negative SST anomalies existed in the SESP(right column in Fig. 2).

    The SST anomalies of the two El Ni?o events showed significant difference even before the El Ni?os started. As shown in Figs. 2a-f, during the late autumn and early winter seasons (October-January) of 1996, negative SST anomalies existed over the CEP (Figs. 2a, d), and the magnitude of the Ni?o3 index (SST anomalies averaged over 5°S-5°N, 90°-150°W) was smaller than -0.5°C (Fig. S9),which is the threshold of a La Ni?a event. In contrast, in late 2014, positive SST anomalies existed over the CEP(Figs. 2b and e, Fig. S9 in the ESM), and 2014 eventually evolved into a weak El Ni?o year (Hu and Fedorov, 2016).Positive SST anomalies over the CEP could induce anomalous convection there and trigger southeasterly wind anomalies in the FEP (Figs. 6a, d).

    At the same time, negative SST anomalies in the SESP also play an active role in triggering the FEP southeasterly wind anomalies (Figs. 6b, e), which usually penetrate into the equatorial Pacific and influence SST variability there(e.g., Su et al., 2014; Zhang et al., 2014; Min et al., 2015;Hu and Fedorov, 2016). Therefore, the strong southeasterly wind anomalies in the FEP during the OND(-1)J(0) (OND denotes October-November-December, -1 and 0 in brackets indicate the preceding year and the El Ni?o year, respectively) season of the 2015/16 event (Figs. 2b, e) are more likely contributed by both the positive SST anomalies over the CEP and negative SST anomalies over the SESP (Figs.6c, f).

    During FM(0) 2015, positive SST anomalies over the CEP decayed (Fig. 2h) and the Ni?o3 index decreased to almost zero (Fig. S9). At the same time, positive SST anomalies over the NESP increased and reached its highest value(Fig. S9). Similar to the positive SST anomalies in the FEP,together with the negative SST anomalies in the SESP, positive SST anomalies over the NESP could trigger cross-equatorial southeasterly wind anomalies by increasing the meridional SST gradient between the NESP and the SESP (Figs.6g-i; Wu et al., 2018).

    Fig. 6. Regressed surface wind anomalies (m s-1) on the standardized SST anomalies averaged in the Ni?o-3 (5°S-5°N,90°-150°W; red boxes in a, d, j), NESP (15°-30°N, 110°-140°W; red box in g), and SESP (20°-30°S, 70°-120°W; blue boxes in b, e, h, k) during October-November (ON), December-January (DJ), February-March (FM), and April-May (AM), respectively.Shading denotes the magnitude of meridional wind anomalies. To better display the impact of cold SESP SST anomalies on the surface wind, the sign of the regressed anomalies on the SESP SST index is reversed. Stippling denotes meridional wind regression coefficients are statistically significant at the 90% confidence level according to two-sided Student’s t-test.

    Fig. 7. Impacts of (a-c) cold SST anomalies in the SESP (20°-30°S, 70°-120°W), (d-f) warm SST anomalies in the NESP(15°-30°N, 110°-140°W), and (g-i) their combined impact on the development of NDJ (November-January) SST anomalies (°C) during the 2015/16 El Ni?o based on numerical sensitivity experiments. Stippling indicates the impacts are statistically significant at the 90% confidence level based on two-sided Student’s t-test.

    In the following AMJJAS(0) season of 2015, positive SST anomalies over the equatorial eastern Pacific started to increase (Figs. 2, S9) because of the strong equatorial westerly wind anomalies and related downwelling Kelvin waves(Figs. 2k, n, q, S3; see also Chen et al., 2017). At the same time, compared to those of the 1997/98 El Ni?o, the preexisting cross-equatorial southeasterly wind anomalies pushed these positive SST anomalies northward (Figs. 2l, o, r). The northward located positive SST anomalies and related convection in turn enhanced the southeasterly wind anomalies in the southeastern Pacific (Zhong et al., 2019) and thus formed a positive feedback between them. In addition, compared to the modest positive SST anomalies in the SESP in the 1997/98 event, the negligible SST anomalies in the SESP in the 2015/16 event might also be favorable to the development of the southeasterly wind anomalies (Figs. 2l,o, r, 6k-l).

    The above analysis suggests that the strong southeasterly wind anomalies in the FEP in the 2015/16 event were triggered and maintained by SST anomalies over different regions during different seasons. Positive SST anomalies over the CEP and NESP and negative SST anomalies over the SESP all contribute to the strengthening of the southeasterly wind anomalies in the FEP. It is worth mentioning that although positive SST anomalies over the NESP could induce southeasterly wind anomalies in the FEP, they could also activate the meridional modes (Chiang and Vimont,2004) and propagate and amplify from the subtropics into the equatorial central Pacific through the winds-evaporation-SST feedback (Figs. 2h, k, n, q), where the positive SST anomalies favor the development of El Ni?o (Alexander et al., 2010). Therefore, the net effect of positive SST anomalies over the NESP on the development of FEP SST anomalies in the 2015/16 event remains unclear and is investigated by numerical experiment in the next section.

    4.2. Model experimental results

    In this section, the possible impacts of SST anomalies over the NESP and SESP, and their combined impacts on the development of FEP SST anomalies in the 2015/16 El Ni?o event are examined by means of numerical experiments (recall Table 1). Figures 7a-c show the impact of SESP SST anomalies on the 2015/16 El Ni?o event. The results indicate that, without the cold SST anomalies in the SESP, positive SST anomalies in the FEP in the CLM_SESP experiment are stronger than those in the OBS_SESP experiment during the mature phase of the El Ni?o (Figs. 7a-c). In addition, SST anomalies in the equatorial central and eastern Pacific in the CLM_SESP experiment would be also stronger than those in the OBS_SESP experiment. This is consistent with previous studies that concluded cold SST anomalies in the southeastern Pacific could have a negative impact on the development of El Ni?o events (e.g., Su et al., 2014; Min et al., 2015; Hu and Fedorov, 2016).

    The evolution of the hindcasted FEP SST anomalies shown in Fig. 8a reveals that the FEP SST anomalies in the OBS_SESP experiment are weaker than those in the CLM_SESP experiment during the entire evolution of the 2015/16 El Ni?o. The difference in the FEP SST anomalies between the two experiments gradually increases since June 2015 and reaches its maximum at the end of 2015. Consistently, the meridional wind anomalies averaged in the FEP in the CLM_SESP experiment are stronger than those in the OBS_SESP experiment (Fig. 8b), which confirms that cold SST anomalies in the SESP could suppress the development of SST anomalies in the FEP by enhancing southerly wind anomalies there. Note that the difference of meridional wind anomalies between the CLM_SESP and OBS_SESP experiments is not significant. This is probably because in the OBS_SESP experiment positive SST anomalies over the CEP are relatively modest. Even though negative SST anomalies exist in the SESP, the SST gradient between the CEP and the SESP is small, which is not conducive to the maintenance and development of southerly wind anomalies in the FEP.

    Fig. 8. Ensemble mean of (a) SST (oC) and (b) meridional wind (m s-1) anomalies averaged over the FEP (0°-15°S,80°-100°W) during April 2015 to January 2016 derived from the NESP sensitivity experiment. (c-d), (e-f) As in (a-b), but for the SESP and BOTH sensitivity experiments. Light red and blue shadings denote ensemble spread, represented by the inter-member standard deviation of the 18 members.

    The impact of positive SST anomalies over the NESP on the 2015/16 El Ni?o event is shown in Figs. 7d-f. It turns out that, although positive SST anomalies over the NESP could induce cross-equatorial southeasterly wind anomalies as is shown in Figs. 6g and 8d, they have a net positive effect on the development of the 2015/16 El Ni?o and thus the SST anomalies in the FEP (Figs. 7d-f). This is because, as mentioned earlier, they could also activate the meridional modes (Chiang and Vimont, 2004), and propagate and amplify from the subtropics into the equatorial central Pacific through the winds-evaporation-SST feedback(Xie and Philander, 1994). The positive SST anomalies over the equatorial central Pacific could induce westerly wind anomalies and favor the development of an El Ni?o event.

    In fact, previous studies have suggested that positive SST anomalies over the NESP might have played an important role in boosting the 2015/16 extreme El Ni?o and hence contributed to the ocean warming in the FEP (e.g., Paek et al., 2017; Su et al., 2018; Zheng et al., 2019), which is consistent with our experimental results (Figs. 7d-f). Therefore, during the 2015/16 El Ni?o, positive SST anomalies over the NESP may have influenced the FEP SST anomalies through two ways: One is that the NESP positive SST anomalies could have induced positive SST anomalies and westerly wind anomalies over the equatorial central Pacific, and thus contributed positively to the development of SST anomalies in the FEP; the other is that the NESP positive SST anomalies could have induced cross-equatorial southeasterly wind anomalies in the FEP, thus being detrimental to the FEP SST development. Although the negative effect(the latter way) would be overwhelmed by the positive effect (the former way), this would cause a slower increase of the FEP SST anomalies than in canonical El Ni?o events to some extent.

    The combined impact of positive SST anomalies over the NESP and negative SST anomalies over the SESP on the 2015/16 El Ni?o event is shown in Figs. 7g-i. We can see that they have a net positive effect on the development of SST anomalies over the FEP. This indicates that the negative effect of the cold SST anomalies in the SESP (Figs.7a-c) is overpowered by the positive effect of the warm SST anomalies in the NESP (Figs. 7d-f). Compared to the NESP experimental result (Figs. 8c-d), the southerly wind anomalies in this experiment are stronger (Fig. 8f) and the positive SST anomalies are weaker (Fig. 8e), which further confirms the negative effect of the cold SESP SST anomalies on the development of FEP SST anomalies.

    Fig. 9. Sea level pressure (shading, Pa) and surface wind (vector, m s-1) anomalies during the developing phase (April to July) of the 1997/98 El Ni?o (left column), the 2015/16 El Ni?o (middle column), and their differences (right column).

    4.3. Effects of sea level pressure on the southeasterly wind anomalies

    Previous studies have suggested that extra-equatorial sea level pressure (SLP) anomalies could have an impact on the evolution of an El Ni?o event by influencing wind anomalies in the tropical Pacific (e.g., Ding et al., 2017; You and Furtado, 2017; Min and Zhang, 2020). Therefore, we compare the South Pacific SLP anomalies in the 1997/98 and 2015/16 events to see if they might also have influenced the southeasterly wind anomalies in the FEP.

    As shown in Fig. 9, surface wind anomalies in the southeastern Pacific are closely related to the SLP anomalies there. In the 1997/98 event, the persistent and significant negative SLP anomaly centers between 25°-50°S might have effectively hindered the southeasterly wind anomalies by inducing northwesterlies in the northeast flank of the cyclone(Figs. 9a, d). This helps explain why the southeasterly wind anomalies were so weak although strong convection occurred over the equatorial central and eastern Pacific during the developing phase of the 1997/98 El Ni?o (recall Figs. 2g, j). In contrast, negative SLP anomalies in the southeastern Pacific in the 2015/16 event were weak and displaced southward; they did not suppress the southeasterly wind anomalies in the FEP (Figs. 9b, e).

    4.4. Possible relationship between the climate decadal variability and the southeasterly wind anomalies

    It is well recognized that there have been systematic changes in background climate conditions over past decades (McPhaden et al., 2011; England et al., 2014; Hu and Fedorov, 2018). Compared to the last two decades of the 20th century, the trade winds were stronger and SSTs were slightly cooler in the east and warmer in the west during the first two decades of the 21st century (Fig. 10). The cooler SSTs and stronger southeasterly winds agree well with the differences between the 1997/98 and 2015/16 El Ni?o events(Figs. 1c, 2).

    Fig. 10. Decadal mean SST (shading, °C) for (a) 1980-99(pre2000), (b) 2000-19 (post2000), and (c) their difference(post2000-pre2000), with surface wind (vector, m s-1)overplotted.

    This indicates that the relatively modest FEP SST anomalies in the 2015/16 El Ni?o may have been related to the decadal changes in background conditions to some extent,but which one caused the other remains unclear (Capotondi et al., 2015). McPhaden et al. (2011) interpreted this similarity between mean and El Ni?o differences to indicate that decadal changes in the background state are the result of(rather than the cause of) a shift in El Ni?o statistics, which are varying naturally. Hu and Fedorov (2018) suggested that the multidecadal strengthening of cross-equatorial winds in the eastern Pacific could have partly contributed to the weakened positive SST anomalies over the eastern Pacific during the El Ni?o events. Considering the complicated mechanisms responsible for the El Ni?o events, more efforts and future studies are certainly required to improve our understanding.

    5. Summary and discussion

    As the first extreme El Ni?o of the 21st century, the 2015/16 El Ni?o is characteristically distinct from the 1997/98 extreme El Ni?o during its peak phase. The largest difference in the SST anomalies between the two extreme El Ni?os appeared in the far eastern Pacific (FEP). Compared to the strong FEP warm SST anomalies in the 1997/98 El Ni?o, the FEP warm SST anomalies in the 2015/16 El Ni?o were modest. In this study, possible causes of the distinct FEP SST anomalies are investigated by observational analysis and numerical experiments. The main findings are given as follows:

    Along with the modest warm SST anomalies in the FEP in the 2015/16 El Ni?o, strong southeasterly wind anomalies existed in the southeastern Pacific during the development of this extreme El Ni?o. In contrast, southeasterly wind anomalies were barely noticeable in the 1997/98 El Ni?o.

    Mixed-layer heat budget analysis indicates that compared to the 1997/98 El Ni?o, the strong southeasterly wind anomalies in the southeastern Pacific might have played an important role in suppressing the FEP SST warming in the 2015/16 El Ni?o by inducing relatively strong upwelling and related westward current, and by enhancing surface evaporation.

    The strong southeasterly wind anomalies in the 2015/16 El Ni?o were initially triggered by the synergistic effects of warm SST anomalies in the CEP and cold SST anomalies in the SESP in the antecedent winter and then sustained by the warm SST anomalies over the NESP and CEP.In contrast, the southeasterly wind anomalies in the 1997/98 event were partly restrained by the significant negative SLP anomalies in the subtropical South Pacific, which may explain why the southeasterly wind anomalies were barely noticeable during the development of the 1997/98 event.

    In addition, the strong southeasterly wind and modest SST anomalies in 2015/16 El Ni?o may also be partly related to the decadal climate variability, with the trade winds being stronger and SSTs being slightly cooler in the east and warmer in the west during the first two decades of the 21st century, compared to the last two decades of the 20th century.

    The strong FEP warm SST anomalies in the 1997/98 El Ni?o were also partly contributed by the strong downward shortwave heat flux because of the positive SST-low-level cloud feedback.

    The significant positive SST anomalies in the northeastern Pacific in winter 2014 and spring 2015 are part of a multi-year warming event lingering from fall 2013 to early 2016 (Di Lorenzo and Mantua, 2016), which has been referred to as a marine heatwave (Hobday et al., 2016) and has had unprecedented impacts on the marine ecosystem(Jones et al., 2018; Piatt et al., 2020). The onset and development of this unusual water mass anomaly in 2013/14 is attributed to forcing associated with a persistent atmospheric ridge over the northeast Pacific (Bond et al., 2015), which is associated with the North Pacific Oscillation (NPO), a leading pattern of atmospheric variability. Furthermore, by conducting correlation analysis and numerical experiments, Di Lorenzo and Mantua (2016) suggested that the persistence and reintensification of the anomaly in 2015 are caused by both the atmospheric forcing and the 2014 El Ni?o teleconnections in the tropical Pacific. And the variance of this NPOlike anomaly pattern may intensify under greenhouse forcing (Wang et al., 2014), hence leading to more extremes in ocean temperature.

    The development of warm SST anomalies in the FEP is affected by various factors, such as coastal meridional winds and zonal wind anomalies over the equatorial western and central Pacific (WCP, Garreaud, 2018; Hu et al.,2019; Peng et al., 2019). This study mainly focuses on the negative impact of anomalous southeasterly winds in the southeastern Pacific on the FEP warm SST anomalies in the 2015/16 El Ni?o. Apart from the southeasterly wind anomalies in the southeastern Pacific, westerly wind anomalies over the WCP during the developing phase of El Ni?o are also a main factor that influences the development of the SST anomalies in the FEP, and strong WCP westerly wind anomalies could induce strong warm SST anomalies in the FEP by inducing significant eastward downwelling Kelvin waves. By calculating accumulated zonal wind stress anomalies, Chen et al. (2017) suggested that the accumulated magnitude of zonal wind stress anomalies over the equatorial western and central Pacific in 2015 was larger than that in 1997 during January-July. Therefore, in contrast to the 1997/98 event, the zonal wind anomalies in the WCP in 2015 might not contribute to the slow increase of the FEP SST anomalies in the 2015/16 event.

    Acknowledgements.This work is jointly supported by National Natural Science Foundation of China (Grant No.42030605), National Key Research and Development Program of China (Grant No. 2019YFC1510004), National Natural Science Foundation of China (Grant Nos. 42088101 and 42005020), the General Program of Natural Science Research of Jiangsu Higher Education Institutions (19KJB170019) and the Natural Science Foundation of Jiangsu Province (Grant No. BK20190781). The model simulation is conducted in the High Performance Computing Center of Nanjing University of Information Science & Technology.HadISST data is downloaded from https://climatedataguide.ucar.edu/climate-data/sst-data-hadisst-v11. The EN4 dataset is from https://www.metoffice.gov.uk/hadobs/en4/. CMAP data, NCEP GODAS data, and NCEP-DOE Reanalysis-2 data are provided by the NOAA/OAR/ESRL PSL, Boulder, Colorado, USA, and are downloaded from https://psl.noaa.gov/. JRA-55 data is from https://rda.ucar.edu/datasets/ds628.1/. ESSO-INCOIS TropFlux data is downloaded from https://incois.gov.in/tropflux/. ISCCP H series cloud data is downloaded from https://www.ncdc.noaa.gov/isccp/isccp-data-access/isccp-basic-data.

    Electronic supplementary material:Supplementary material is available in the online version of this article at https://doi.org/10.1007/s00376-021-1263-z.

    a 毛片基地| 亚洲一区中文字幕在线| 777米奇影视久久| 天天操日日干夜夜撸| 考比视频在线观看| 久热爱精品视频在线9| 久久久精品94久久精品| 母亲3免费完整高清在线观看| 国产又色又爽无遮挡免| 亚洲成人免费电影在线观看| 啦啦啦视频在线资源免费观看| 一区二区av电影网| 成年美女黄网站色视频大全免费| 91成人精品电影| 热99国产精品久久久久久7| 高清av免费在线| 国产精品偷伦视频观看了| 99re6热这里在线精品视频| 丰满饥渴人妻一区二区三| 50天的宝宝边吃奶边哭怎么回事| 亚洲熟女精品中文字幕| 精品少妇黑人巨大在线播放| 国产亚洲精品第一综合不卡| 又紧又爽又黄一区二区| 成人亚洲精品一区在线观看| 亚洲精品在线美女| 国产免费一区二区三区四区乱码| 老司机福利观看| 青草久久国产| 成在线人永久免费视频| 国产主播在线观看一区二区| 国产精品一区二区精品视频观看| 国产精品一区二区在线不卡| 成年人黄色毛片网站| 黄色视频,在线免费观看| 久久精品国产亚洲av香蕉五月 | 91字幕亚洲| 少妇猛男粗大的猛烈进出视频| 老司机午夜十八禁免费视频| 久久久久久久久久久久大奶| 亚洲男人天堂网一区| 亚洲精品国产av蜜桃| 亚洲欧美日韩另类电影网站| 中文字幕av电影在线播放| 精品久久久久久电影网| 精品福利永久在线观看| 热99久久久久精品小说推荐| 丝瓜视频免费看黄片| 老司机影院成人| 我的亚洲天堂| 99热网站在线观看| 最近最新免费中文字幕在线| 大香蕉久久网| 国产主播在线观看一区二区| 在线观看人妻少妇| 国产视频一区二区在线看| 91九色精品人成在线观看| 亚洲精品国产色婷婷电影| 精品久久久久久电影网| 国产av又大| 亚洲色图 男人天堂 中文字幕| 天天操日日干夜夜撸| 欧美精品高潮呻吟av久久| 欧美国产精品va在线观看不卡| 国产一区二区在线观看av| 国产成人影院久久av| 国产一区二区三区在线臀色熟女 | 精品视频人人做人人爽| 麻豆乱淫一区二区| 又黄又粗又硬又大视频| 真人做人爱边吃奶动态| 久久综合国产亚洲精品| 久久久精品94久久精品| av片东京热男人的天堂| 一进一出抽搐动态| 51午夜福利影视在线观看| 精品少妇黑人巨大在线播放| 人妻 亚洲 视频| 天天躁夜夜躁狠狠躁躁| 午夜激情av网站| 91九色精品人成在线观看| 两个人看的免费小视频| 色综合欧美亚洲国产小说| 欧美另类一区| 久久久国产一区二区| 精品国产乱码久久久久久小说| 中国美女看黄片| 亚洲一码二码三码区别大吗| 日韩熟女老妇一区二区性免费视频| 久久中文看片网| 天天影视国产精品| 999久久久国产精品视频| 极品少妇高潮喷水抽搐| 少妇 在线观看| 高清欧美精品videossex| 久久精品国产综合久久久| 精品一区二区三区av网在线观看 | 国产在线免费精品| 欧美激情 高清一区二区三区| 国产一卡二卡三卡精品| 久久精品aⅴ一区二区三区四区| 午夜影院在线不卡| 日韩制服丝袜自拍偷拍| 婷婷成人精品国产| 久热爱精品视频在线9| 一本大道久久a久久精品| 一级毛片精品| 国产av国产精品国产| 最近最新免费中文字幕在线| 狠狠婷婷综合久久久久久88av| 男女之事视频高清在线观看| 国产男女超爽视频在线观看| 久久久国产精品麻豆| 日韩熟女老妇一区二区性免费视频| 精品人妻熟女毛片av久久网站| 一本一本久久a久久精品综合妖精| 男女无遮挡免费网站观看| tube8黄色片| 老熟女久久久| 好男人电影高清在线观看| 777久久人妻少妇嫩草av网站| 热99国产精品久久久久久7| 男男h啪啪无遮挡| 国产1区2区3区精品| 中文字幕av电影在线播放| 黑人欧美特级aaaaaa片| 亚洲国产中文字幕在线视频| 一本—道久久a久久精品蜜桃钙片| 日本wwww免费看| av福利片在线| 国产熟女午夜一区二区三区| 99热国产这里只有精品6| 如日韩欧美国产精品一区二区三区| 精品国产乱子伦一区二区三区 | 国产成人欧美| 国产视频一区二区在线看| 婷婷色av中文字幕| 欧美成人午夜精品| 国产亚洲av高清不卡| 丰满饥渴人妻一区二区三| 国产日韩欧美视频二区| 蜜桃国产av成人99| 国产日韩欧美视频二区| 韩国高清视频一区二区三区| 精品少妇一区二区三区视频日本电影| 国产精品国产三级国产专区5o| 又紧又爽又黄一区二区| 老熟妇乱子伦视频在线观看 | 亚洲成人免费电影在线观看| 777久久人妻少妇嫩草av网站| 成年人午夜在线观看视频| 亚洲欧美日韩另类电影网站| 国产精品一区二区精品视频观看| 97精品久久久久久久久久精品| 超碰97精品在线观看| 中文字幕制服av| 日韩制服丝袜自拍偷拍| 亚洲 国产 在线| 国产野战对白在线观看| av天堂在线播放| 999久久久国产精品视频| 丝袜在线中文字幕| 国产精品影院久久| tube8黄色片| 精品一区二区三卡| 美女中出高潮动态图| 在线观看免费视频网站a站| 久久精品国产亚洲av香蕉五月 | 91麻豆av在线| 欧美一级毛片孕妇| 亚洲第一欧美日韩一区二区三区 | 午夜福利在线免费观看网站| 大陆偷拍与自拍| 老司机影院毛片| 亚洲欧美一区二区三区黑人| 亚洲av日韩在线播放| 亚洲一码二码三码区别大吗| 久久久久国内视频| 免费在线观看黄色视频的| 亚洲av男天堂| 大码成人一级视频| 亚洲精品国产一区二区精华液| 丰满迷人的少妇在线观看| 免费久久久久久久精品成人欧美视频| 亚洲欧洲精品一区二区精品久久久| 黄片播放在线免费| 国产一区二区 视频在线| 亚洲国产中文字幕在线视频| 丰满迷人的少妇在线观看| 99国产精品99久久久久| 午夜日韩欧美国产| 777久久人妻少妇嫩草av网站| 欧美日韩黄片免| 中文字幕制服av| 99久久人妻综合| 精品一区二区三卡| 久久亚洲精品不卡| 欧美黄色片欧美黄色片| 日韩三级视频一区二区三区| 叶爱在线成人免费视频播放| 久久天躁狠狠躁夜夜2o2o| 麻豆国产av国片精品| 午夜老司机福利片| 操出白浆在线播放| 两人在一起打扑克的视频| 国产片内射在线| 9色porny在线观看| 久久 成人 亚洲| 两性午夜刺激爽爽歪歪视频在线观看 | 天天躁夜夜躁狠狠躁躁| 午夜福利视频在线观看免费| 精品视频人人做人人爽| 久久久欧美国产精品| 啦啦啦 在线观看视频| 亚洲七黄色美女视频| 久久性视频一级片| 久久久精品国产亚洲av高清涩受| 91麻豆av在线| 黄片播放在线免费| 久久 成人 亚洲| 亚洲专区国产一区二区| av线在线观看网站| 国产精品久久久av美女十八| 日韩电影二区| 亚洲成人国产一区在线观看| 五月开心婷婷网| 久久久久久久久久久久大奶| 成人黄色视频免费在线看| 成年女人毛片免费观看观看9 | 咕卡用的链子| 久久精品亚洲熟妇少妇任你| 另类精品久久| 日韩欧美国产一区二区入口| 啦啦啦免费观看视频1| 一本一本久久a久久精品综合妖精| 久久女婷五月综合色啪小说| 69av精品久久久久久 | 久久天躁狠狠躁夜夜2o2o| 18在线观看网站| 日韩有码中文字幕| 多毛熟女@视频| 99久久综合免费| 国产精品99久久99久久久不卡| 在线观看人妻少妇| 午夜免费观看性视频| 国产av精品麻豆| 国产精品成人在线| 日本猛色少妇xxxxx猛交久久| 真人做人爱边吃奶动态| 99国产精品一区二区三区| 又紧又爽又黄一区二区| 日本五十路高清| 国产91精品成人一区二区三区 | 国产精品九九99| 精品福利永久在线观看| 黄片大片在线免费观看| 日本vs欧美在线观看视频| 国产高清国产精品国产三级| 国产成+人综合+亚洲专区| 热re99久久精品国产66热6| 搡老岳熟女国产| 岛国毛片在线播放| 亚洲精华国产精华精| 极品人妻少妇av视频| 成人18禁高潮啪啪吃奶动态图| 超碰成人久久| 啦啦啦啦在线视频资源| 国产一区有黄有色的免费视频| 老汉色av国产亚洲站长工具| 天天操日日干夜夜撸| 国产极品粉嫩免费观看在线| 日本猛色少妇xxxxx猛交久久| 免费一级毛片在线播放高清视频 | 亚洲一区二区三区欧美精品| 国产成人免费观看mmmm| 精品国内亚洲2022精品成人 | 午夜福利一区二区在线看| 色94色欧美一区二区| 极品人妻少妇av视频| 黄色怎么调成土黄色| 手机成人av网站| 99国产极品粉嫩在线观看| 亚洲,欧美精品.| 99国产精品一区二区蜜桃av | 天堂俺去俺来也www色官网| 少妇精品久久久久久久| 日韩,欧美,国产一区二区三区| 久久久久久久久久久久大奶| 亚洲人成电影观看| 各种免费的搞黄视频| 精品国产乱子伦一区二区三区 | 亚洲性夜色夜夜综合| av福利片在线| 久久国产精品人妻蜜桃| 欧美激情久久久久久爽电影 | 大码成人一级视频| 亚洲欧美一区二区三区久久| 亚洲精品第二区| h视频一区二区三区| 国产老妇伦熟女老妇高清| 久久久久久人人人人人| 欧美老熟妇乱子伦牲交| 久久人妻熟女aⅴ| 久久久久久亚洲精品国产蜜桃av| 亚洲 欧美一区二区三区| 麻豆乱淫一区二区| 啦啦啦免费观看视频1| 成在线人永久免费视频| 99久久精品国产亚洲精品| 窝窝影院91人妻| 国产无遮挡羞羞视频在线观看| 91麻豆精品激情在线观看国产 | 纵有疾风起免费观看全集完整版| 久久精品久久久久久噜噜老黄| 亚洲情色 制服丝袜| 亚洲国产精品成人久久小说| 午夜福利视频在线观看免费| 午夜福利,免费看| 午夜福利在线观看吧| 国产精品亚洲av一区麻豆| 黑人操中国人逼视频| 久久久久久久国产电影| 国产一区二区三区综合在线观看| 视频在线观看一区二区三区| 色综合欧美亚洲国产小说| 在线观看舔阴道视频| 亚洲国产欧美日韩在线播放| 亚洲男人天堂网一区| 中文欧美无线码| 久久午夜综合久久蜜桃| 黄色视频在线播放观看不卡| 欧美精品高潮呻吟av久久| 交换朋友夫妻互换小说| 午夜激情久久久久久久| 欧美性长视频在线观看| 午夜福利视频在线观看免费| 国产精品av久久久久免费| 日韩大片免费观看网站| 咕卡用的链子| 老熟女久久久| 免费观看人在逋| 桃花免费在线播放| 国产亚洲精品一区二区www | 国产黄频视频在线观看| 欧美精品av麻豆av| 精品少妇一区二区三区视频日本电影| 久久亚洲精品不卡| 永久免费av网站大全| 中文字幕色久视频| 精品卡一卡二卡四卡免费| 亚洲少妇的诱惑av| 久久女婷五月综合色啪小说| 一本—道久久a久久精品蜜桃钙片| 黑人操中国人逼视频| 国产日韩欧美亚洲二区| 亚洲av日韩在线播放| av网站在线播放免费| 亚洲专区字幕在线| 精品国产一区二区三区四区第35| 久久人妻熟女aⅴ| 十分钟在线观看高清视频www| 美国免费a级毛片| 在线观看www视频免费| 99精品欧美一区二区三区四区| 香蕉国产在线看| 久久久久久久精品精品| 每晚都被弄得嗷嗷叫到高潮| 老汉色av国产亚洲站长工具| 别揉我奶头~嗯~啊~动态视频 | 美女中出高潮动态图| 国产精品久久久久久人妻精品电影 | 99re6热这里在线精品视频| 波多野结衣一区麻豆| 色视频在线一区二区三区| 飞空精品影院首页| 国产在线免费精品| 亚洲伊人久久精品综合| 国产精品一区二区精品视频观看| 91麻豆精品激情在线观看国产 | 69精品国产乱码久久久| 午夜福利视频精品| 巨乳人妻的诱惑在线观看| 51午夜福利影视在线观看| √禁漫天堂资源中文www| 97精品久久久久久久久久精品| 国产一卡二卡三卡精品| 亚洲美女黄色视频免费看| 精品高清国产在线一区| 午夜影院在线不卡| 日韩人妻精品一区2区三区| 国产一区二区 视频在线| 18禁观看日本| 国产亚洲精品久久久久5区| 亚洲欧洲日产国产| 999精品在线视频| 午夜福利在线免费观看网站| 91麻豆av在线| 亚洲精品第二区| 亚洲国产日韩一区二区| 精品一区二区三区四区五区乱码| av不卡在线播放| 日韩视频在线欧美| 欧美日韩成人在线一区二区| 91大片在线观看| 欧美+亚洲+日韩+国产| 日韩欧美免费精品| 丰满人妻熟妇乱又伦精品不卡| 中文字幕制服av| 免费女性裸体啪啪无遮挡网站| www.熟女人妻精品国产| 亚洲精品在线美女| 国产一区二区三区在线臀色熟女 | 国产97色在线日韩免费| 手机成人av网站| 99精品欧美一区二区三区四区| 一进一出抽搐动态| www日本在线高清视频| 成年动漫av网址| 久久九九热精品免费| 国产成人精品久久二区二区免费| 亚洲第一av免费看| 中亚洲国语对白在线视频| 两个人看的免费小视频| 午夜福利一区二区在线看| 亚洲天堂av无毛| 无限看片的www在线观看| 蜜桃在线观看..| 视频区图区小说| 亚洲一区中文字幕在线| 欧美黄色片欧美黄色片| 久久久精品国产亚洲av高清涩受| 岛国在线观看网站| 大香蕉久久网| 美女扒开内裤让男人捅视频| 亚洲 国产 在线| 99国产精品一区二区蜜桃av | 久久毛片免费看一区二区三区| 99精品久久久久人妻精品| 色婷婷久久久亚洲欧美| 欧美老熟妇乱子伦牲交| 日韩大片免费观看网站| 欧美日韩福利视频一区二区| 99九九在线精品视频| 另类亚洲欧美激情| 国产欧美日韩综合在线一区二区| www日本在线高清视频| 国产欧美日韩精品亚洲av| 可以免费在线观看a视频的电影网站| 久久国产精品影院| 黄色视频不卡| 熟女少妇亚洲综合色aaa.| 久久久久久久国产电影| 欧美在线一区亚洲| 日日夜夜操网爽| 亚洲国产看品久久| 欧美人与性动交α欧美精品济南到| 夜夜骑夜夜射夜夜干| 久久久欧美国产精品| 日本撒尿小便嘘嘘汇集6| 国产视频一区二区在线看| 亚洲性夜色夜夜综合| 久久综合国产亚洲精品| 一个人免费看片子| 亚洲熟女精品中文字幕| 岛国在线观看网站| 欧美激情极品国产一区二区三区| 法律面前人人平等表现在哪些方面 | 男女无遮挡免费网站观看| 最黄视频免费看| 国产精品久久久久久精品电影小说| 久久女婷五月综合色啪小说| 中文字幕最新亚洲高清| 久久久精品免费免费高清| 18在线观看网站| 热99国产精品久久久久久7| www.av在线官网国产| 夫妻午夜视频| 女人高潮潮喷娇喘18禁视频| 一区二区三区精品91| a级毛片黄视频| 老司机影院毛片| 青春草亚洲视频在线观看| 91成人精品电影| 亚洲天堂av无毛| 精品福利观看| 日韩欧美免费精品| 啦啦啦中文免费视频观看日本| 两个人免费观看高清视频| 日本vs欧美在线观看视频| 亚洲三区欧美一区| 啪啪无遮挡十八禁网站| 天天躁日日躁夜夜躁夜夜| 在线精品无人区一区二区三| 国产激情久久老熟女| 女人高潮潮喷娇喘18禁视频| 日本av免费视频播放| 9热在线视频观看99| 黄色视频,在线免费观看| 人人妻人人添人人爽欧美一区卜| 日韩电影二区| 成人国产av品久久久| 欧美日韩国产mv在线观看视频| 精品乱码久久久久久99久播| 熟女少妇亚洲综合色aaa.| 久久精品国产a三级三级三级| 中文欧美无线码| 国产精品免费视频内射| 肉色欧美久久久久久久蜜桃| 国精品久久久久久国模美| 亚洲第一青青草原| 自拍欧美九色日韩亚洲蝌蚪91| 天天躁夜夜躁狠狠躁躁| 黄片大片在线免费观看| 曰老女人黄片| 国产亚洲精品久久久久5区| 日日爽夜夜爽网站| 亚洲国产精品999| 午夜久久久在线观看| 91成人精品电影| 亚洲国产av影院在线观看| 悠悠久久av| 青草久久国产| 久久国产精品影院| 老鸭窝网址在线观看| 国产精品久久久久成人av| 午夜福利免费观看在线| 成人18禁高潮啪啪吃奶动态图| 精品一区二区三卡| 日韩中文字幕视频在线看片| 亚洲精品一区蜜桃| 亚洲人成电影免费在线| 国产精品一二三区在线看| 母亲3免费完整高清在线观看| 国产亚洲精品一区二区www | av在线播放精品| 99re6热这里在线精品视频| 久久ye,这里只有精品| 久久狼人影院| 成人国语在线视频| 国产精品久久久av美女十八| 亚洲国产av影院在线观看| 免费在线观看影片大全网站| 亚洲五月婷婷丁香| 久久久久国产精品人妻一区二区| 亚洲精品中文字幕一二三四区 | 精品卡一卡二卡四卡免费| 亚洲国产日韩一区二区| 黄片播放在线免费| 亚洲视频免费观看视频| 法律面前人人平等表现在哪些方面 | 亚洲,欧美精品.| 一级毛片电影观看| 一区福利在线观看| 成人三级做爰电影| 天天影视国产精品| 中文字幕色久视频| 免费黄频网站在线观看国产| 亚洲国产av新网站| 精品亚洲乱码少妇综合久久| 三级毛片av免费| av线在线观看网站| 国产成人一区二区三区免费视频网站| 婷婷色av中文字幕| 中文欧美无线码| 啦啦啦啦在线视频资源| 91国产中文字幕| 国产精品1区2区在线观看. | 丰满人妻熟妇乱又伦精品不卡| 欧美黄色淫秽网站| 成人国产一区最新在线观看| 国产极品粉嫩免费观看在线| 老熟妇仑乱视频hdxx| 制服诱惑二区| 成人av一区二区三区在线看 | 久久久久国产精品人妻一区二区| 亚洲av欧美aⅴ国产| 老司机在亚洲福利影院| 啪啪无遮挡十八禁网站| 久久久久网色| 国产精品久久久久久人妻精品电影 | 国产精品秋霞免费鲁丝片| 天天躁夜夜躁狠狠躁躁| 久久精品久久久久久噜噜老黄| 午夜精品国产一区二区电影| 中文字幕人妻熟女乱码| 18禁观看日本| 日本wwww免费看| 十八禁高潮呻吟视频| 日韩大片免费观看网站| 国产一区有黄有色的免费视频| e午夜精品久久久久久久| 乱人伦中国视频| 久久这里只有精品19| 嫩草影视91久久| 18禁黄网站禁片午夜丰满| 丝瓜视频免费看黄片| 国产精品秋霞免费鲁丝片| 亚洲av成人不卡在线观看播放网 | 午夜两性在线视频| 汤姆久久久久久久影院中文字幕| 老司机靠b影院| 午夜精品久久久久久毛片777| 欧美+亚洲+日韩+国产| 人人妻人人澡人人看| 丝瓜视频免费看黄片| 日韩一卡2卡3卡4卡2021年| 极品少妇高潮喷水抽搐| 成人国语在线视频| 成年动漫av网址| 久久国产精品人妻蜜桃| 精品少妇黑人巨大在线播放| 久久 成人 亚洲| 亚洲性夜色夜夜综合| 久久久久网色| 久久精品成人免费网站|