North Australian Sea Surface Temperatures and the El Niño–Southern Oscillation in Observations and Models

Abstract Interannual variations in the sea surface temperature (SST) to the north of Australia are strongly linked to variations in Australian climate, including winter rainfall and tropical cyclone numbers. The north Australian SSTs are also closely linked to ENSO and tropical Pacific SSTs, with the relationship exhibiting a strong seasonal cycle. Credible predictions of Australian climate change therefore depend on climate models being able to represent ENSO and its connection to north Australian SSTs, the topic of this study. First, the observational datasets of the Met Office Hadley Centre Sea Ice and Sea Surface Temperature (HadISST) and the NOAA Extended Reconstructed Sea Surface Temperature (ERSST) are used to document the links between the Niño-3.4 index and a north Australian SST index, and the temporal evolution of north Australian SSTs during ENSO events. During austral autumn, the correlation between Niño-3.4 SST and north Australian SST is positive, while in austral spring it is strongly negative. During El Niño events, the north Australian SST anomalies become negative in the austral spring preceding the development of the positive Niño-3.4 SST anomalies. The coupled models participating in the Coupled Model Intercomparison Project phase 3 (CMIP3) are evaluated in terms of this temporal evolution of Niño-3.4 SST and the relationship to north Australian SST for the twentieth-century simulations. Some of the models perform very well, while some do not capture the seasonal cycle of correlations at all. The way in which these relationships may change in the future is examined using the A2 emissions scenario in those models that do a reasonable job of capturing the present-day observed relationship, and very little change is found.

Download Full-text

Recent intensified influence of the winter North Pacific sea surface temperature on the withdrawal date of Meiyu

Journal of Climate ◽

10.1175/jcli-d-19-0768.1 ◽

2021 ◽

pp. 1-53

Author(s):

Hua Li ◽

Shengping He ◽

Ke Fan ◽

Yong Liu ◽

Xing Yuan

Keyword(s):

Surface Temperature ◽

Sea Surface Temperature ◽

Interannual Variability ◽

North Pacific ◽

North Pacific Ocean ◽

Sea Surface ◽

The North ◽

Time Period ◽

The North Pacific ◽

Sst Anomalies

AbstractThe Meiyu withdrawal date (MWD) is a crucial indicator of flood/drought conditions over East Asia. It is characterized by a strong interannual variability, but its underlying mechanism remains unknown. We investigated the possible effects of the winter sea surface temperature (SST) in the North Pacific Ocean on the MWD on interannual to interdecadal timescales. Both our observations and model results suggest that the winter SST anomalies associated with the MWD are mainly contributed by a combination of the first two leading modes of the winter SST in the North Pacific, which have a horseshoe shape (the NPSST). The statistical results indicate that the intimate linkage between the NPSST and the MWD has intensified since the early 1990s. During the time period 1990–2016, the NPSST-related SST anomalies persisted from winter to the following seasons and affected the SST over the tropical Pacific in July. Subsequently, the SST anomalies throughout the North Pacific strengthened the southward migration of the East Asian jet stream (EAJS) and the southward and westward replacement of the western North Pacific subtropical high (WPSH), leading to an increase in Meiyu rainfall from July 1 to 20. More convincingly, the anomalous EAJS and WPSH induced by the SST anomalies can be reproduced well by numerical simulations. By contrast, the influence of the NPSST on the EASJ and WPSH were not clear between 1961 and 1985. This study further illustrates that the enhanced interannual variability of the NPSST may be attributed to the more persistent SST anomalies during the time period 1990–2016.

Download Full-text

Global Monsoon Responses to Decadal Sea Surface Temperature Variations during the Twentieth Century: Evidence from AGCM Simulations

Journal of Climate ◽

10.1175/jcli-d-18-0890.1 ◽

2019 ◽

Vol 32 (22) ◽

pp. 7675-7695 ◽

Cited By ~ 3

Author(s):

Jie Jiang ◽

Tianjun Zhou

Keyword(s):

Twentieth Century ◽

Surface Temperature ◽

Sea Surface Temperature ◽

Atmospheric Circulation ◽

North Atlantic ◽

Sea Surface ◽

Monsoon Precipitation ◽

The North ◽

The North Atlantic ◽

Sst Anomalies

Abstract Multidecadal variations in the global land monsoon were observed during the twentieth century, with an overall increasing trend from 1901 to 1955 that was followed by a decreasing trend up to 1990, but the mechanisms governing the above changes remain inconclusive. Based on the outputs of two atmospheric general circulation models (AGCMs) forced by historical sea surface temperature (SST) covering the twentieth century, supplemented with AGCM simulations forced by idealized SST anomalies representing different conditions of the North Atlantic and tropical Pacific, evidence shows that the observed changes can be partly reproduced, particularly over the Northern Hemisphere summer monsoon (NHSM) domain, demonstrating the modulation of decadal SST changes on the long-term variations in monsoon precipitation. Moisture budget analysis is performed to understand the interdecadal changes in monsoon precipitation, and the dynamic term associated with atmospheric circulation changes is found to be prominent, while the contribution of the thermodynamic term associated with humidity changes can lead to coincident wetting over the NHSM domain. The increase (decrease) in NHSM land precipitation during 1901–55 (1956–90) is associated with the strengthening (weakening) of NHSM circulation and Walker circulation. The multidecadal scale changes in atmospheric circulation are driven by SST anomalies over the North Atlantic and the Pacific. A warmer North Atlantic together with a colder eastern tropical Pacific and a warmer western subtropical Pacific can lead to a strengthened meridional gradient in mid-to-upper-tropospheric thickness and strengthened trade winds, which transport more water vapor into monsoon regions, leading to an increase in monsoon precipitation.

Download Full-text

TC-Permitting GCM Simulations of Hurricane Frequency Response to Sea Surface Temperature Anomalies Projected for the Late-Twenty-First Century

Journal of Climate ◽

10.1175/jcli-d-11-00313.1 ◽

2012 ◽

Vol 25 (8) ◽

pp. 2995-3009 ◽

Cited By ~ 85

Author(s):

Ming Zhao ◽

Isaac M. Held

Keyword(s):

Surface Temperature ◽

Sea Surface Temperature ◽

Frequency Response ◽

North Atlantic ◽

First Century ◽

Sea Surface ◽

The North ◽

Storm Frequency ◽

The North Atlantic ◽

Sst Anomalies

Abstract A tropical cyclone–permitting global atmospheric model is used to explore the hurricane frequency response to sea surface temperature (SST) anomalies generated by coupled models for the late-twenty-first century. Results are presented for SST anomalies averaged over 18 models as well as from 8 individual models. For each basin, there exists large intermodel spread in the magnitude and even the sign of the frequency response among the different SST projections. These sizable variations in response are explored to understand features of SST distributions that are important for the basin-wide hurricane responses. In the North Atlantic, the eastern Pacific, and the southern Indian basins, most (72%–86%) of the intermodel variance in storm frequency response can be explained by a simple relative SST index defined as a basin’s storm development region SST minus the tropical mean SST. The explained variance is significantly lower in the South Pacific (48%) and much lower in the western Pacific basin (27%). Several atmospheric parameters are utilized to probe changes in tropical atmospheric circulation and thermodynamical properties relevant to storm genesis in the model. While all present strong correlation to storm response in some basins, a parameter-measuring tropospheric convective mass flux stands out as skillful in explaining the simulated differences for all basins. Globally, in addition to a modest reduction of total storm frequency, the simulations exhibit a small, but robust eastward and poleward migration of genesis frequency in both the North Pacific and the North Atlantic Oceans. This eastward migration of storms can also be explained by changes in convection.

Download Full-text

Appearance of the common paper nautilus Argonauta argo related to the increase of the sea surface temperature in the north-eastern Atlantic

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315402006240 ◽

2002 ◽

Vol 82 (5) ◽

pp. 855-858 ◽

Cited By ~ 12

Author(s):

A. Guerra ◽

A.F. González ◽

F. Rocha

Keyword(s):

Surface Temperature ◽

Sea Surface Temperature ◽

First Record ◽

Mature Female ◽

Sea Surface ◽

North West ◽

The North ◽

North Eastern ◽

The Common ◽

The Relationship

The relationship between the increase of the sea surface temperature observed off the Galician coast and the appearance of a tropical poikilotherm species Argonauta argo in these coasts is discussed. This is the first record of Argonautaargo in the north-west Iberian Peninsula. A female of this species was captured alive near the surface at dusk on 22 December 2000 in the Ria de Aldán (42°15′N–08°48′W). The specimen, a mature female of 70 mm mantle length and 96 mm shell diameter, died 36 hours after introduction in the tank.

Download Full-text

Feedbacks of Sea Surface Temperature to Wintertime Storm Tracks in the North Atlantic

Journal of Climate ◽

10.1175/jcli-d-13-00719.1 ◽

2014 ◽

Vol 28 (1) ◽

pp. 306-323 ◽

Cited By ~ 12

Author(s):

Bolan Gan ◽

Lixin Wu

Keyword(s):

Surface Temperature ◽

Sea Surface Temperature ◽

North Atlantic ◽

Storm Track ◽

Early Spring ◽

Sea Surface ◽

Storm Tracks ◽

The North ◽

The North Atlantic ◽

Sst Anomalies

Abstract In this study, the lagged maximum covariance analysis is performed on winter storm-track anomalies, represented by the meridional heat flux by synoptic-scale (2–8 days) transient eddies and sea surface temperature (SST) anomalies in the North Atlantic, which are both derived from reanalysis datasets spanning the twentieth century. The analysis shows significant seasonal and interannual coupling between storm-track and SST variations. On seasonal time scales, it is found that SST anomalies in the preceding early winter (November–December), which are expected to change the lower-tropospheric baroclinicity, can significantly influence storm tracks in early spring (March); that is, an intensification and slight northward shift of storm tracks in response to a midlatitude SST dipole, with a cold pole centered to the southeast of Newfoundland and a warm pole in the western subtropical Atlantic. This storm-track response pattern is similar to the storm-track forcing pattern in early spring, which resembles the dominant mode of storm tracks. At interannual time scales, it is found that the wintertime (January–March) storm-track and SST anomalies are mutually reinforced, manifesting as a zonal-dipole-like pattern in storm-track anomalies (with dominant negative anomalies in the downstream) coupled with a midlatitude SST monopole (with warm anomalies centered to the south and east of Newfoundland).

Download Full-text

Impact of Sea Surface Temperature Anomalies in the Equatorial and North Pacific on the Arctic Stratosphere According to INMCM5 Climate Model Simulations

Meteorologiya i Gidrologiya ◽

10.52002/0130-2906-2021-1-5-16 ◽

2021 ◽

pp. 5-16

Author(s):

P. N. Vargin ◽

◽

M. A. Kolennikova ◽

S. V. Kostrykin ◽

E. M. Volodin ◽

...

Keyword(s):

Surface Temperature ◽

Sea Surface Temperature ◽

North Pacific ◽

Climate Model ◽

Sea Surface ◽

The Arctic ◽

The North ◽

Stratospheric Temperature ◽

Climate Model Simulations ◽

Sst Anomalies

Five 50-year simulations with version 5 of the INM RAS coupled climate model revealed that the winters with El Nio are characterized by higher Arctic stratospheric temperature as compared to the seasons with La Nia. Lower stratospheric temperature in the Arctic regions as compared to the seasons with negative sea surface temperature (SST) anomalies corresponds to the winter seasons with positive SST anomalies in the North Pacific.

Download Full-text

Seasonal and Long-Term Coupling between Wintertime Storm Tracks and Sea Surface Temperature in the North Pacific

Journal of Climate ◽

10.1175/jcli-d-12-00724.1 ◽

2013 ◽

Vol 26 (16) ◽

pp. 6123-6136 ◽

Cited By ~ 26

Author(s):

Bolan Gan ◽

Lixin Wu

Keyword(s):

Surface Temperature ◽

Sea Surface Temperature ◽

North Pacific ◽

Storm Track ◽

Sea Surface ◽

Storm Tracks ◽

The North ◽

The North Pacific ◽

Sst Anomalies

Abstract In this study, a lagged maximum covariance analysis (MCA) of the wintertime storm-track and sea surface temperature (SST) anomalies derived from the reanalysis datasets shows significant seasonal and long-term relationships between storm tracks and SST variations in the North Pacific. At seasonal time scales, it is found that the midlatitude warm (cold) SST anomalies in the preceding fall, which are expected to change the tropospheric baroclinicity, can significantly reduce (enhance) the storm-track activities in early winter. The storm-track response pattern, however, is in sharp contrast to the forcing pattern, with warm (cold) SST anomalies in the western–central North Pacific corresponding to a poleward (equatorward) shift of storm tracks. At interannual-to-decadal time scales, it is found that the wintertime SST and storm-track anomalies are mutually reinforced up to 3 yr, which is characterized by PDO-like SST anomalies with warming in the western–central domain coupled with basin-scale positive storm-track anomalies extending along 50°N.

Download Full-text

Assessment of responses of North Atlantic winter sea surface temperature to the North Atlantic Oscillation on an interannual scale in 13 CMIP5 models

Ocean Science ◽

10.5194/os-16-1509-2020 ◽

2020 ◽

Vol 16 (6) ◽

pp. 1509-1527

Author(s):

Yujie Jing ◽

Yangchun Li ◽

Yongfu Xu

Keyword(s):

Heat Flux ◽

Surface Temperature ◽

North Atlantic ◽

Sea Surface ◽

The North ◽

The North Atlantic ◽

Relationship Of ◽

The Relationship ◽

Interannual Scale ◽

Sst Anomalies

Abstract. This study evaluates the response of winter-average sea surface temperature (SST) to the winter North Atlantic Oscillation (NAO) simulated by 13 Coupled Model Intercomparison Project Phase 5 (CMIP5) Earth system models in the North Atlantic (NA) (0–65∘ N) on an interannual scale. Most of the models can reproduce an observed tripolar pattern of the response of the SST anomalies to the NAO on an interannual scale. The model bias is mainly reflected in the locations of the negative-response centers in the subpolar NA (45–65∘ N), which is mainly caused by the bias of the response of the SST anomalies to the NAO-driven turbulent heat flux (THF) anomalies. Although the influence of the sensible heat flux (SHF) on the SST is similar to that of the latent heat flux (LHF), it seems that the SHF may play a larger role in the response of the SST to the NAO, and the weak negative response of the SST anomalies to the NAO-driven LHF anomalies is mainly caused by the overestimated oceanic role in the interaction of the LHF and SST. Besides the THF, some other factors which may impact the relationship of the NAO and SST are discussed. The relationship of the NAO and SST is basically not affected by the heat meridional advection transports on an interannual timescale, but it may be influenced by the cutoffs of data filtering, the initial fields, and external-forcing data in some individual models, and in the tropical NA it can also be affected by the different definitions of the NAO indices.

Download Full-text

Summertime Evolution of Decadal Sea Surface Temperature Anomalies in the Midlatitude North Pacific

Journal of Climate ◽

10.1175/2007jcli1853.1 ◽

2008 ◽

Vol 21 (7) ◽

pp. 1569-1588 ◽

Cited By ~ 4

Author(s):

Takashi Mochizuki ◽

Toshiyuki Awaji

Keyword(s):

Surface Temperature ◽

Sea Surface Temperature ◽

North Pacific ◽

Radiation Flux ◽

Sea Surface ◽

Shortwave Radiation ◽

The North ◽

Sst Anomaly ◽

The North Pacific ◽

Sst Anomalies

Abstract To clarify the summertime evolution of decadal sea surface temperature (SST) anomalies and related physical processes in the midlatitudes of the North Pacific, numerical solutions of a three-dimensional bulk mixed layer model are analyzed, focusing on the contribution of the net shortwave radiative forcing at the sea surface. A quantitative heat budget analysis for the ocean mixed layer relating to late-1980s decadal SST change reveals that the decadal SST anomalies decay from late spring to early summer over the entire midlatitudes of the North Pacific. This quasi-seasonal decay of the decadal SST anomalies is controlled by an anomalous local thermal damping (i.e., anomalous surface heat fluxes). From midsummer to early autumn the anomalous net shortwave radiation flux associated with a meridional shift of the storm track acts to induce strong seasonal damping of the decadal SST anomaly in the northern Kuroshio–Oyashio Extension region. In contrast, in the north of the subtropical frontal region, the net shortwave radiation flux anomaly, which results from changes in low-level stratiform cloud cover, plays a major role in seasonally enhancing the decadal SST anomaly. Consequently, the SST anomalies formed by these radiative forcings cause significant variations in the local thermal damping rate at the sea surface over the period from late summer to early autumn.

Download Full-text