Satellite and in situ observations in the equatorial Atlantic Ocean during 2002–03 show dominant spectral peaks at 40–60 days and secondary peaks at 10–40 days in sea level and thermocline within the intraseasonal period band (10–80 days). A detailed investigation of the dynamics of the intraseasonal variations is carried out using an ocean general circulation model, namely, the Hybrid Coordina...

A new all-sky imaging Fabry-Perot spectrometer has been installed at Mawson station (6736 S, 6252 E), Antarctica. This instrument is capable of recording independent spectra from many tens of locations across the sky simultaneously. Useful operation began in March 2007, with spectra recorded on a total of 186 nights. Initial analysis has focused on the large-scale daily and average behavior of ...

The turnabout and growth mechanisms of the ENSO are diagnostically studied by analyzing the SST budget of the Cane-Zebiak model. The SST change rates, which are directly linked to the phase transition and growth of the ENSO, are attributed to two processes: the anomalous vertical advection of subsurface temperature by the mean upwelling (thermocline feedback), and the zonal advection of the cli...

We use incoherent scatter radar measurements from Millstone Hill and Saint Santin to study the midlatitude F region electrodynamic plasma drifts during geomagnetically quiet and active periods. We present initially a local time, season, and solar flux dependent analytical model of the quiet time zonal and meridional ExB drifts over these stations. We discuss, for the first time, the Saint Santi...

The ocean thermohaline circulation, also called meridional overturning circulation, is caused by water density contrasts. This circulation has large capacity of carrying heat around the globe and it thus affects the energy budget and further affects the climate. We consider a thermohaline circulation model in the meridional plane under external wind forcing. We show that, when there is no wind ...

To understand solar cycle signals on the Earth’s surface and identify the physical mechanisms responsible, surface 10 temperature variations from observations as well as climate model data are analyzed to characterize their spatial structure. The solar signal in the annual mean surface temperature is characterized by i) mid-latitude warming and ii) no overall tropical warming. The mid-latitude ...

The value of the analyses of the 200 mbar zonal winds is proposed as a particularly effective tool to assess variability and trends in atmospheric circulation. Using the thermal wind relation, the 200 mbar zonal wind results from the vertically integrated north-south temperature gradient between the Earth’s surface and 200 mbar. We found a tendency for the 200 mbar winds to become somewhat stro...

Abstract Weather systems in the southern Indian Ocean (SIO) drive synoptic-scale precipitation variability East Antarctica and Australia. Improved understanding of these dynamical linkages is beneficial to diagnose long-term climate changes from proxy records as well informing regional weather forecasts. Self-organizing maps (SOMs) are used group daily 500-hPa geopotential height (z500; ERA-Int...

EISCAT radar experiments over a full solar cycle between January 1984 and March 1995 have been used to construct meridional neutral wind patterns in the ionospheric F region. For locally geomagnetically quiet periods the neutral winds have been binned according to season, solar activity, and universal time. The diurnal and seasonal behaviors and the e€ect of the solar ̄ux are described. An empi...

Global Positioning System radio occultation measurements by the FORMOsa SATellite mission3/Constellation Observing System for Meteorology, Ionosphere and Climate satellites were used to analyse the behaviour of the signature of the terdiurnal tide in sporadic E (ES) layers at midlatitudes (43–63 N). According to theory, the occurrence of ES is expected when the vertical zonal wind shear, which ...