Regional Climate Impacts of the Northern Hemisphere Annular Mode

Thompson, David W. J.; Wallace, John M.

doi:10.1126/science.1058958

Cited by 784 publications

(548 citation statements)

References 18 publications

Supporting

Mentioning

501

Contrasting

Unclassified

Order By: Relevance

“…Ambaum et al, 2001;Thompson and Wallace, 2001, and references therein). In its negative phase, the latter has been linked to enhanced ridging occurrences over both the Euro-Atlantic and the North Pacific Alaskan sector, east of the dateline (Thompson and Wallace, 2001). In our view, the NAM index is not sufficient, as it is nearly equivalent to using the zonalmean zonal winds (e.g.…”

Section: Discussionmentioning

confidence: 99%

Variability of the Northern Hemisphere polar stratospheric cloud potential: the role of North Pacific disturbances

Orsolini

Karpechko

Nikulin

2009

Quart J Royal Meteoro Soc

View full text Add to dashboard Cite

ABSTRACT:The potential of the Arctic stratosphere to sustain the formation of Polar Stratospheric Clouds (PSCs) is a key factor in determining the amount of ozone destroyed each winter, and is often measured as a 'PSC volume'. The latter quantity has been shown to closely follow a near-linear compact relationship with winter-averaged column ozone loss, and displays a high variability from monthly to decadal time-scales. We examine the connection between meteorological conditions in the troposphere and the variability of lower polar stratospheric temperatures over the last four decades, and specifically, conditions leading to a high PSC volume. In addition to the well-established connection between the North Atlantic Oscillation (NAO) and the polar vortex, we demonstrate the large influence of precursory disturbances over the North Pacific and the Far East, the region of maximum climatological upward wave activity flux. Namely, very high monthly PSC volume (in the top 12%) predominantly follows the development of positive tropospheric height anomalies over the Far East, which lead to a weakening of the background planetary wave trough, and lessened upward wave activity flux into the stratosphere. Precursory anomalies over the Far East are reminiscent of East Asian monsoon amplification episodes.

show abstract

Section: Discussionmentioning

confidence: 99%

Variability of the Northern Hemisphere polar stratospheric cloud potential: the role of North Pacific disturbances

Orsolini

Karpechko

Nikulin

2009

Quart J Royal Meteoro Soc

View full text Add to dashboard Cite

show abstract

“…These are the North Atlantic Oscillation index (NAO), the Indian Ocean Dipole (IOD), the Pacific Decadal Oscillation (PDO), the Multivariate ENSO Index (MEI). We used the following indices: (Thompson & Wallace, 2001)), which also goes by the name of the North Atlantic Oscillation (NAO; (Hurrell, 1995)). The North Atlantic Oscillation (NAO) index is typically measured through variations in the normal pattern of lower atmospheric pressure over Iceland and higher pressure near the Azores and Iberian Peninsula (Jones et al, 1997).…”

Section: Climate Indicesmentioning

confidence: 99%

The response of African land surface phenology to large scale climate oscillations

Brown

Beurs

Vrieling

2010

Remote Sensing of Environment

130

View full text Add to dashboard Cite

Variations in agricultural production due to rainfall and temperature fluctuations are a primary cause of food insecurity on the African continent. Analysis of changes in phenology can provide quantitative information on the effect of climate variability on growing seasons in agricultural regions. Using a robust statistical methodology, we describe the relationship between phenology metrics derived from the 26 year AVHRR NDVI record and the North Atlantic Oscillation index (NAO), the Indian Ocean Dipole (IOD), the Pacific Decadal Oscillation (PDO), and the Multivariate ENSO Index (MEI). We map the most significant positive and negative correlation for the four climate indices in Eastern, Western and Southern Africa between two phenological metrics and the climate indices. Our objective is to provide evidence of whether climate variability captured in the four indices has had a significant impact on the vegetative productivity of Africa during the past quarter century. We found that the start of season and cumulative NDVI were significantly affected by large scale variations in climate. The particular climate index and the timing showing highest correlation depended heavily on the region examined. In Western Africa the cumulative NDVI correlates with PDO in September-November. In Eastern Africa the start of the June-October season strongly correlates with PDO in March-May, while the PDO in December-February correlates with the start of the FebruaryJune season. The cumulative NDVI over this last season relates to the MEI of March-May. For Southern Africa, high correlations exist between SOS and NAO of September-November, and cumulative NDVI and MEI of March-May. The research shows that climate indices can be used to anticipate late start and variable vigor in the growing season of sensitive agricultural regions in Africa.Published by Elsevier Inc.

show abstract

“…The NAWA represents the out-ofphase relationships between normalized SLP over NA and WA (see Paz et al, 2003, for further details). Following Paz et al (2003) study, relationships between NAWA and the Eastern Mediterranean winter climate were further explored (Tourre and Paz, 2004), and the NAWA index was also viewed as the regional signature of the hemispheric northern annular mode (NAM as defined by Thompson and Wallace, 2001). Interestingly enough, NAM is directly associated with the variability and strength of the stratospheric polar vortex (Thompson et al, 2002).…”

mentioning

confidence: 99%

Multitemporal climate variability over the Atlantic Ocean and Eurasia: linkages with Mediterranean and West African climate

Paz

Tourre

Brolley³

2008

Atmospheric Science Letters

View full text Add to dashboard Cite

More linkages between the Atlantic multidecadal oscillation (AMO, and thermohaline circulation), the Polar vortex oscillation (PVO, and vorticity intrusion), the North Africa-West Asia index (NAWA, and NA-WA poles) and Sahelian rainfall, are investigated. Significant positive correlations are found between winter/spring AMO and spring NA pole. Significant positive (negative) correlations are found between winter PVO and NAWA (WA pole). NAWA is shown being modulated by winter AMO to the west, and winter PVO over Eurasia to the east. Winter AMO and PVO can thus be used operationally by decision makers as early predictors of Mediterranean climate and Sahelian rainfall during summer.

show abstract

Regional Climate Impacts of the Northern Hemisphere Annular Mode

Cited by 784 publications

References 18 publications

Variability of the Northern Hemisphere polar stratospheric cloud potential: the role of North Pacific disturbances

Variability of the Northern Hemisphere polar stratospheric cloud potential: the role of North Pacific disturbances

The response of African land surface phenology to large scale climate oscillations

Multitemporal climate variability over the Atlantic Ocean and Eurasia: linkages with Mediterranean and West African climate

Contact Info

Product

Resources

About