1. introduction while human habitation was formed as concentrated and stable communities, air pollution had become perceptible on human life. by passing of time and the improvement of thriving and particularly by the industrial revolution commencement, air pollution gradually has converted into an international issue, principally in the present times (ghanbari and azizi, 1388: 16). whereas air ...

Satellite measurements are often compared with higher-precision ground-based measurements as part of validation efforts. The satellite soundings are rarely perfectly coincident in space and time with the ground-based measurements, so a colocation methodology is needed to aggregate “nearby” soundings into what the instrument would have seen at the location and time of interest. We are particular...

In order to detect ultrahigh-energy cosmic rays (UHECR), atmospheric fluorescence light from the trajectory of the extensive air shower may be measured by mirrorphotosensor systems. In this type of experiment the photon yield from electrons exciting air of various densities and temperatures is most fundamental information for estimating the primary energy of UHECR. An experiment has been undert...

â â â  in this research, temporal and spatial behaviors of azores high pressure was studied at the level of 700 hpa. this study has been done using daily data of geopotential height at 12 gmt in ncep/ncar database with spatial resolution of 2.5*2.5 degree in a 55 years period including 20089 days from january, 1st, 1951(dey, 11th, 1329) to december, 31st,2005(dey, 10th,1384). at first, the mean...

Temperature trends in the UTLS region are under-reported, particularly in the Southern Hemisphere, and yet temperature is one of the most important indicators of changes in dynamical and radiative processes in the atmosphere. Here radiosonde data from Durban, South Africa (30.0 S, 30.9 E) over the period 1980 to 2001 (22 years) between 250 and 20 hPa are used to derive a mean temperature climat...

A possibly new teleconnection has been discovered off the east coast of Australia in the region around Tasman sea and Southern Ocean. Found in pressure anomalies using a novel graph based approach called shared reciprocal nearest neighbors, this dipole appears in reanalysis datasets such as NCEP, JRA, ERA and MERRA. The HadSLP2 observation data shows the new dipole, despite of limited observati...