The Summer North Atlantic Oscillation: Past, Present, and Future

Folland, Chris K.; Knight, Jeff; Linderholm, Hans W.; Fereday, David; Ineson, Sarah; Hurrell, James W.

doi:10.1175/2008jcli2459.1

Cited by 619 publications

(753 citation statements)

References 55 publications

Supporting

Mentioning

652

Contrasting

Unclassified

Order By: Relevance

“…The model results do, however, indicate 5-10% less summer rainfall over Britain, consistent with Lamb's (1965) reconstruction for medieval times (see also Proctor et al 2000;Charman et al 2006), this in association with a well developed ''summer NAO'' SLP pattern (Folland et al 2008; Fig. 8).…”

Section: Relation To Other Modeling Studies Using Warmer Indian Oceansupporting

confidence: 71%

Support for global climate reorganization during the “Medieval Climate Anomaly”

et al. 2010

View full text Add to dashboard Cite

Widely distributed proxy records indicate that the Medieval Climate Anomaly (MCA; *900-1350 AD) was characterized by coherent shifts in large-scale Northern Hemisphere atmospheric circulation patterns. Although cooler sea surface temperatures in the central and eastern equatorial Pacific can explain some aspects of medieval circulation changes, they are not sufficient to account for other notable features, including widespread aridity through the Eurasian sub-tropics, stronger winter westerlies across the North Atlantic and Western Europe, and shifts in monsoon rainfall patterns across Africa and South Asia. We present results from a full-physics coupled climate model showing that a slight warming of the tropical Indian and western Pacific Oceans relative to the other tropical ocean basins can induce a broad range of the medieval circulation and climate changes indicated by proxy data, including many of those not explained by a cooler tropical Pacific alone. Important aspects of the results resemble those from previous simulations examining the climatic response to the rapid Indian Ocean warming during the late twentieth century, and to results from climate warming simulations-especially in indicating an expansion of the Northern Hemisphere Hadley circulation. Notably, the pattern of tropical Indo-Pacific sea surface temperature (SST) change responsible for producing the proxy-model similarity in our results agrees well with MCA-LIA SST differences obtained in a recent proxy-based climate field reconstruction. Though much remains unclear, our results indicate that the MCA was characterized by an enhanced zonal Indo-Pacific SST gradient with resulting changes in Northern Hemisphere tropical and extra-tropical circulation patterns and hydroclimate regimes, linkages that may explain the coherent regional climate shifts indicated by proxy records from across the planet. The findings provide new perspectives on the nature and possible causes of the MCA-a remarkable, yet incompletely understood episode of Late Holocene climatic change.

show abstract

Section: Relation To Other Modeling Studies Using Warmer Indian Oceansupporting

confidence: 71%

Support for global climate reorganization during the “Medieval Climate Anomaly”

et al. 2010

View full text Add to dashboard Cite

show abstract

“…This is consistent with the rise in anticyclonic weather conditions experienced in the last decades of the twentieth century (Folland et al, 2009).…”

Section: Discussionsupporting

confidence: 87%

A comparative study of the magnitude, frequency and distribution of intense rainfall in the United Kingdom

Rodda¹,

Little

Rodda³

et al. 2009

Intl Journal of Climatology

View full text Add to dashboard Cite

During the 1960s, a study was made of the magnitude, frequency and distribution of intense rainfall over the United Kingdom, employing data from more than 120 daily read rain gauges covering the period 1911 to 1960. Using the same methodology, that study was recently updated utilizing data for the period 1961 to 2006 for the same gauges, or from those nearby. This paper describes the techniques applied to ensure consistency of data and statistical modelling. It presents a comparison of patterns of extreme rainfalls for the two periods and discusses the changes that have taken place. Most noticeably, increases up to 20% have occurred in the north-west of the country and in parts of East Anglia. There have also been changes in other areas, including decreases of the same magnitude over central England. The implications of these changes are considered.

show abstract

“…Relatively weak precipitation variations of opposite sign are revealed north and south of the above region. This mode is associated with the summer NAO [e.g., Zveryaev, 2004;Folland et al, 2009]. Since anomalies in atmospheric circulation during summer are not as large as during winter and because precipitation is one of the most variable climate parameters, it is not obvious to expect the revealed stability of the first mode of summer precipitation.…”

Section: Summary and Discussionmentioning

confidence: 99%

Summertime precipitation variability over Europe and its links to atmospheric dynamics and evaporation

Zveryaev

Allan

2010

J. Geophys. Res.

View full text Add to dashboard Cite

[1] Gridded monthly precipitation data for 1979-2006 from the Global Precipitation Climatology Project are used to investigate interannual summer precipitation variability over Europe and its links to regional atmospheric circulation and evaporation. The first empirical orthogonal function (EOF) mode of European precipitation, explaining 17.2%-22.8% of its total variance, is stable during the summer season and is associated with the North Atlantic Oscillation. The spatial-temporal structure of the second EOF mode is less stable and shows month-to-month variations during the summer season. This mode is linked to the Scandinavian teleconnection pattern. Analysis of links between leading EOF modes of regional precipitation and evaporation has revealed a significant link between precipitation and evaporation from the European land surface, thus, indicating an important role of the local processes in summertime precipitation variability over Europe. Weaker, but statistically significant links have been found for evaporation from the surface of the Mediterranean and Baltic Seas. Finally, in contrast to winter, no significant links have been revealed between European precipitation and evaporation in the North Atlantic during the summer season.Citation: Zveryaev, I. I., and R. P. Allan (2010), Summertime precipitation variability over Europe and its links to atmospheric dynamics and evaporation,

show abstract

The Summer North Atlantic Oscillation: Past, Present, and Future

Cited by 619 publications

References 55 publications

Support for global climate reorganization during the “Medieval Climate Anomaly”

Support for global climate reorganization during the “Medieval Climate Anomaly”

A comparative study of the magnitude, frequency and distribution of intense rainfall in the United Kingdom

Summertime precipitation variability over Europe and its links to atmospheric dynamics and evaporation

Contact Info

Product

Resources

About