Annually resolved Atlantic sea surface temperature variability over the past 2,900 y

Global warming due to anthropogenic factors can be amplified or dampened by natural climate oscillations, especially those involving sea surface temperatures (SSTs) in the North Atlantic which vary on a multidecadal scale (Atlantic multidecadal variability, AMV). Because the instrumental record of AMV is short, long-term behavior of AMV is unknown, but climatic teleconnections to regions beyond the North Atlantic offer the prospect of reconstructing AMV from high-resolution records elsewhere. Annually resolved titanium from an annually laminated sedimentary record from Ellesmere Island, Canada, shows that the record is strongly influenced by AMV via atmospheric circulation anomalies. Significant correlations between this High-Arctic proxy and other highly resolved Atlantic SST proxies demonstrate that it shares the multidecadal variability seen in the Atlantic. Our record provides a reconstruction of AMV for the past ∼3 millennia at an unprecedented time resolution, indicating North Atlantic SSTs were coldest from ∼1400–1800 CE, while current SSTs are the warmest in the past ∼2,900 y.

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Impact of Seasonality in the North Atlantic Jet Stream and Storm Migration on the Seasonality of Hurricane Translation Speed Changes

Journal of Climate ◽

10.1175/jcli-d-20-0642.1 ◽

2021 ◽

pp. 1-38

Author(s):

Xi Guo ◽

James P. Kossin ◽

Zhe-Min Tan

Keyword(s):

North Atlantic ◽

Atlantic Coast ◽

Jet Stream ◽

Translation Speed ◽

Multidecadal Variability ◽

The Past ◽

The North ◽

Term Variation ◽

The North Atlantic

AbstractTropical cyclone (TC) translation speed (TCTS) can affect the duration of TC-related disasters, which is critical to coastal and inland areas. The long-term variation of TCTS and their relationship to the variability of the mid-latitude jet stream and storm migration are discussed here for storms near the North Atlantic coast during 1948-2019. Our results reveal the prominent seasonality in the long-term variation of TCTS, which can be largely explained by the seasonality in the covariations of the mid-latitude jet stream and storm locations. Specifically, significant increases of TCTS occur in June and October during the past decades, which may result from the equatorward displacement of the jet stream and poleward migration of storm locations. Prominent slowdown of TCTS is found in August, which is related to the weakened jet strength and equatorward storm migration. In September, the effects of poleward displacement and weakening of the jet stream on TCTS are largely compensated by the poleward storm migration, therefore, no significant change in TCTS is observed. Meanwhile, the multidecadal variability of the Atlantic may contribute to the multidecadal variability of TCTS. Our findings emphasize the significance in taking a seasonality view in discussing the variability and trends of near-coast Atlantic TCTS under climate change.

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Modeled and Observed Multidecadal Variability in the North Atlantic Jet Stream and Its Connection to Sea Surface Temperatures

Journal of Climate ◽

10.1175/jcli-d-18-0168.1 ◽

2018 ◽

Vol 31 (20) ◽

pp. 8313-8338 ◽

Cited By ~ 16

Author(s):

Isla R. Simpson ◽

Clara Deser ◽

Karen A. McKinnon ◽

Elizabeth A. Barnes

Keyword(s):

North Atlantic ◽

Sea Surface ◽

Late Winter ◽

Jet Stream ◽

Sea Surface Temperatures ◽

Multidecadal Variability ◽

The North ◽

Surface Temperatures ◽

The North Atlantic ◽

North Atlantic Jet

Multidecadal variability in the North Atlantic jet stream in general circulation models (GCMs) is compared with that in reanalysis products of the twentieth century. It is found that almost all models exhibit multidecadal jet stream variability that is entirely consistent with the sampling of white noise year-to-year atmospheric fluctuations. In the observed record, the variability displays a pronounced seasonality within the winter months, with greatly enhanced variability toward the late winter. This late winter variability exceeds that found in any GCM and greatly exceeds expectations from the sampling of atmospheric noise, motivating the need for an underlying explanation. The potential roles of both external forcings and internal coupled ocean–atmosphere processes are considered. While the late winter variability is not found to be closely connected with external forcing, it is found to be strongly related to the internally generated component of Atlantic multidecadal variability (AMV) in sea surface temperatures (SSTs). In fact, consideration of the seasonality of the jet stream variability within the winter months reveals that the AMV is far more strongly connected to jet stream variability during March than the early winter months or the winter season as a whole. Reasoning is put forward for why this connection likely represents a driving of the jet stream variability by the SSTs, although the dynamics involved remain to be understood. This analysis reveals a fundamental mismatch between late winter jet stream variability in observations and GCMs and a potential source of long-term predictability of the late winter Atlantic atmospheric circulation.

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The impact of Atlantic and Pacific Ocean sea surface temperature anomalies on the North Atlantic multidecadal variability

Tellus A Dynamic Meteorology and Oceanography ◽

10.1111/j.1600-0870.2008.00304.x ◽

2008 ◽

Vol 60 (4) ◽

pp. 728-741 ◽

Cited By ~ 9

Author(s):

KLAUS GROSFELD ◽

GERRIT LOHMANN ◽

NOREL RIMBU

Keyword(s):

Pacific Ocean ◽

Surface Temperature ◽

North Atlantic ◽

Sea Surface ◽

Atlantic Multidecadal Variability ◽

Multidecadal Variability ◽

The North ◽

Sea Surface Temperature Anomalies ◽

The North Atlantic ◽

The Impact

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Enhanced western Mediterranean rainfall during past interglacials driven by North Atlantic pressure changes

10.5194/cp-2019-75 ◽

2019 ◽

Author(s):

Yama Dixit ◽

Samuel Toucanne ◽

Juan M. Lora ◽

Christophe Fontanier ◽

Virgil Pasquier ◽

...

Keyword(s):

North Atlantic ◽

Western Mediterranean ◽

Sea Surface ◽

Tyrrhenian Sea ◽

Winter Rainfall ◽

The Past ◽

The North ◽

Hydrological Changes ◽

The North Atlantic ◽

The Mediterranean

Abstract. There is increasing concern with anthropogenic greenhouse gas emissions that ocean warming, in concert with summer and winter precipitation changes, will induce anoxia in multiple ocean basins. In particular the Mediterranean Sea is susceptible to severe hydrological changes. Mediterranean hydroclimate is controlled primarily by two phenomena – the latitudinal migration of the Inter-Tropical Convergence Zone and the North Atlantic climatic processes. While the former brings about the African summer monsoon rainfall the latter drives the wintertime storm tracks into the western Mediterranean. Although the hydrological changes in the eastern Mediterranean are quite well constrained, evidence of past changes in temperature and rainfall in the western Mediterranean across the past interglacials is relatively scarce. In this study, we use trace element and stable isotope composition of planktonic foraminifera from a sediment core off Corsica at the mouth of Golo river in the western Mediterranean to reconstruct variations in sea surface temperature (SST) and sea surface salinities (SSS) during the Holocene and warm periods of the past two interglacials. Our data suggest that the warm periods of the last interglacials were characterised by high river discharge and lower SSS in the northern Tyrrhenian Sea, suggesting increased winter rainfall. We find evidence that enhanced winter rainfall during periods of precession minima and high seasonality across interglacials coincide with changes in the respective eccentricity maxima suggesting a causal link. Our model simulations for representative orbital configurations such as the mid-Holocene support increased south-westerly moisture transport into the western Mediterranean originating from the North Atlantic. We suggest that these hydrologic changes in the western and the northern Mediterranean borderlands were a contributing factor to basin-wide anoxia in the past. Our findings offer new insights into the cause and impact of winter rainfall changes in the Mediterranean during past warm periods.

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The impact of Atlantic and Pacific Ocean sea surface temperature anomalies on the North Atlantic multidecadal variability

Tellus A Dynamic Meteorology and Oceanography ◽

10.3402/tellusa.v60i4.15300 ◽

2008 ◽

Cited By ~ 2

Author(s):

Klaus Grosfeld ◽

Gerrit Lohmann ◽

Norel Rimbu

Keyword(s):

Pacific Ocean ◽

Surface Temperature ◽

North Atlantic ◽

Sea Surface ◽

Atlantic Multidecadal Variability ◽

Multidecadal Variability ◽

The North ◽

Sea Surface Temperature Anomalies ◽

The North Atlantic ◽

The Impact

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Have Aerosols Caused the Observed Atlantic Multidecadal Variability?

Journal of the Atmospheric Sciences ◽

10.1175/jas-d-12-0331.1 ◽

2013 ◽

Vol 70 (4) ◽

pp. 1135-1144 ◽

Cited By ~ 210

Author(s):

Rong Zhang ◽

Thomas L. Delworth ◽

Rowan Sutton ◽

Daniel L. R. Hodson ◽

Keith W. Dixon ◽

...

Keyword(s):

Twentieth Century ◽

North Atlantic ◽

Heat Content ◽

Sea Surface ◽

Sea Surface Salinity ◽

Shortwave Radiation ◽

Multidecadal Variability ◽

The North ◽

The North Atlantic ◽

Aerosol Effects

Abstract Identifying the prime drivers of the twentieth-century multidecadal variability in the Atlantic Ocean is crucial for predicting how the Atlantic will evolve in the coming decades and the resulting broad impacts on weather and precipitation patterns around the globe. Recently, Booth et al. showed that the Hadley Centre Global Environmental Model, version 2, Earth system configuration (HadGEM2-ES) closely reproduces the observed multidecadal variations of area-averaged North Atlantic sea surface temperature in the twentieth century. The multidecadal variations simulated in HadGEM2-ES are primarily driven by aerosol indirect effects that modify net surface shortwave radiation. On the basis of these results, Booth et al. concluded that aerosols are a prime driver of twentieth-century North Atlantic climate variability. However, here it is shown that there are major discrepancies between the HadGEM2-ES simulations and observations in the North Atlantic upper-ocean heat content, in the spatial pattern of multidecadal SST changes within and outside the North Atlantic, and in the subpolar North Atlantic sea surface salinity. These discrepancies may be strongly influenced by, and indeed in large part caused by, aerosol effects. It is also shown that the aerosol effects simulated in HadGEM2-ES cannot account for the observed anticorrelation between detrended multidecadal surface and subsurface temperature variations in the tropical North Atlantic. These discrepancies cast considerable doubt on the claim that aerosol forcing drives the bulk of this multidecadal variability.

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Downstream impact of the North Pacific subtropical sea surface temperature front on the North Atlantic westerly jet stream in winter

Atmospheric Research ◽

10.1016/j.atmosres.2021.105492 ◽

2021 ◽

Vol 253 ◽

pp. 105492

Author(s):

Leying Zhang ◽

Haiming Xu ◽

Jing Ma ◽

Jiuwei Zhao ◽

Xia Xu

Keyword(s):

Surface Temperature ◽

Sea Surface Temperature ◽

North Atlantic ◽

North Pacific ◽

Sea Surface ◽

Jet Stream ◽

The North ◽

Westerly Jet ◽

The North Atlantic ◽

The North Pacific

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Space-Time Sea Surface pCO2 Estimation in the North Atlantic Based on CatBoost

Remote Sensing ◽

10.3390/rs13142805 ◽

2021 ◽

Vol 13 (14) ◽

pp. 2805

Author(s):

Hongwei Sun ◽

Junyu He ◽

Yihui Chen ◽

Boyu Zhao

Keyword(s):

North Atlantic ◽

Function Analysis ◽

Biological Activities ◽

Mixed Layer Depth ◽

Sea Surface ◽

Coefficient Of Determination ◽

Mean Bias Error ◽

Bias Error ◽

The North ◽

The North Atlantic

Sea surface partial pressure of CO2 (pCO2) is a critical parameter in the quantification of air–sea CO2 flux, which plays an important role in calculating the global carbon budget and ocean acidification. In this study, we used chlorophyll-a concentration (Chla), sea surface temperature (SST), dissolved and particulate detrital matter absorption coefficient (Adg), the diffuse attenuation coefficient of downwelling irradiance at 490 nm (Kd) and mixed layer depth (MLD) as input data for retrieving the sea surface pCO2 in the North Atlantic based on a remote sensing empirical approach with the Categorical Boosting (CatBoost) algorithm. The results showed that the root mean square error (RMSE) is 8.25 μatm, the mean bias error (MAE) is 4.92 μatm and the coefficient of determination (R2) can reach 0.946 in the validation set. Subsequently, the proposed algorithm was applied to the sea surface pCO2 in the North Atlantic Ocean during 2003–2020. It can be found that the North Atlantic sea surface pCO2 has a clear trend with latitude variations and have strong seasonal changes. Furthermore, through variance analysis and EOF (empirical orthogonal function) analysis, the sea surface pCO2 in this area is mainly affected by sea temperature and salinity, while it can also be influenced by biological activities in some sub-regions.

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