The Temporal And Spatial Variations Of The Northern Hemisphere Troposphere Thickness And Its Relationship With Atmospheric Circulation And SST

We use monthly geopotential height of the NCEP/NCAR reanalysis data(2.5°×2.5°) and sst data of NOAA (2.0°×2.0°) for the63-yr period of1948—2010respectively, defined1000hPa and200hPa geopotential height difference500hPa and200hPa geopotential height difference and1000hPa the500hPa geopotential height difference as the thickness of the troposphere, the thickness of the upper troposphere and lower troposphere thickness.the Temporal and spatial variations of the Northern Hemisphere troposphere thickness and its relationship with atmospheric circulation has been analysised by means of EOF and SVD,etc. The main conclusions are as follows:Because the lower part of the thickness mainly force by the thermal factor and the upper part mainly force by the dynamical factor, so the temporal and spatial variations of the annual average winter average and summer average of1000～500hPa and500～200hPa thickness are significant different, especially in high and middle latitudes.The impact of atmospheric circulation on the troposphere thickness is very important.When the sea level pressure anomalies of the North Pacific and the polar regions biased the Eastern Hemisphere are anti-phase distribution, the lower thickness is the PNA type in winter.When the sip anomalies of the North Atlantic and the polar regions are anti-phase, the lower part of the thickness of the eastern and western hemisphere high latitudes is anti-phase in winter.When the winter500hPa geopotential height anomalies of the east and west coasts of Eurasia are negative phase but the central Eurasia, the polar regions and high-latitude areas of the North American continent are positive, the upper thickness is the PNA type.When the500hPa geopotential height of the northern Europe and North Pacific region is unusually high, the convective layer thickness of Eurasia is exceptionally low.Summer when the sip of the Pacific the low-latitude Eurasia region and the polar regions are positive anomalies, that of the Atlantic Ocean, the high latitudes Eurasia and the the North America mainland are negative anomalies, the lower part thickness mainly shows consistent positive anomalies in hemisphere ereas.When the slp field is characterized by the polar regions’s positive anomalies, the other areas are negative, there is a similar anomaly distribution in the thickness field.The upper part thickness mainly exists the Eurasian type.The thickness anomalies not only due to the dynamic processes of the atmosphere, the sea surface temperature force can not be ignored. This study indicate that large-scale quasi-stationary heat source (such as the tropical Pacific warm pool eastern, the Pacific cold pool, in addition to the tropical Indian Ocean, the tropical Atlantic), can affect the entire troposphere. In generally speaking, the sea surface temperature thermal forcing on convection layer thickness is particularly significant in its surrounding areas. When La Nina or ENSO is prevailing, the Eastern Pacific sea surface temperature anomaly can force a wide range consistent anomaly phase in middle and high latitude troposphere thickness. And the Northern Hemisphere troposphere thickness has a similar shock period to the tropical Pacific sea surface temperature cycle.