Below normal high pressure at high latitudes, above normal heights at the East Coast, and in West Europe, changed location of the jet stream and storm track, above average temperatures in the eastern US, northern Europe, below normal temperatures in Greenland, south Europe and the middle East
multi-decadal
Greenland, North America between 35-40N
Positive PNA tends to occur with El Nino, negative with Pacific cold periods of La Nina.
It's anorth-south anomaly, low frequency variability over the North Atlantic southward shifted NAO with a subtropical link. This pattern is distinctly different from the NAO.
7 months, multi-decadal for wintertime NAO
Neigative height anomaly over the polar region, positive anomaly over North China and Mongolia.
Fluctuations in the circumpolar circulation. The positive phase means an enhanced vortex as compared to the normal.
Above average heights over the inter-mountain region of North America, below average heights over the Aleutian and southeastern US.
Mena temperatures are above normal is East Siberia, below normal in East China, and precipitation is above normal over the pole and Scandinavia.
Positive EA has above normal temperatures in Europe in all months, below normal temperatures in the southern US in January to May and in the coastal US in July to October, above normal precipitation in southern Europe
PNA is a low frequency variability in the northerm hemispheric tropics.
Where are the anomaly centers in NAO?
Recall what the East Atlantic pattern is.
Recall what PNA is.
How would you describe the temperature and precipitation pattern of the East Atlantic pattern?
Recall the typical variability.
Recall the NAO interannual variability
Recall what the positive phase of the Polar Eurasia means.
Recall how PNA is influenced by ENSO.
Explain what causes the Polar Eurasia.
Recall what the positive Polar Eurasia means precipitation and temperature wise.
How would you describe the positive NAO?
Describe what the positivve phase PNA means temperature, and precipitation wise.
