Short-Period Variations in the Ionosphere

Short period fluctuations in the characteristics of wireless echoes from the ionosphere

A new experim ental techn ique is described for study ing th e d irectional an d po larization characteristics of wireless echoes. The m ethod m akes use of an o rd inary spaced fram e direction-finding system , com bined w ith a tw inchannel am plifier an d ca thode-ray tu b e , so th a t by observations of an ellipse on th e screen th e phases an d am plitudes of th e e.m .f.s in th e aerial ...

Short-period solar cycle signals in the ionosphere observed by FORMOSAT-3/COSMIC

[1] We analyze 2 years of the FORMOSAT-3/COSMIC GPS radio occultation data to study the response of the Earth’s ionosphere to the solar rotation (27-day) induced solar flux variations. Here we report electron density variations in the ionosphere ( 100–500 km) associated with the 27-day solar cycle. The peak-to-peak variation in electron density at low latitudes in the F2 region is about 10–10 e...

The response of the high-latitude ionosphere to IMF variations

The convection of plasma in the high-latitude ionosphere is strongly a2ected by the interplanetary magnetic 3eld (IMF) carried by the solar wind. From numerous statistical studies, it is known that the plasma circulation conforms to patterns that are characteristic of particular IMF states. Following a change in the IMF, the convection responds by recon3guring into a pattern that is more consis...

The Quality Variations of the Drinking Water Sources in the Rural Regions of Sabzevar County in a Five Year Period

Background and purpose: Water is the most important limiting factor of sustainable development. Poor quality of water sources and lack of appropriate management in some regions are the main reasons of water crises in the country. This study was conducted to assess water sources quality and the trend of their change in rural area of Sabzevar County in a five year period. Materials and Met...

Short communication: Morphometric, growth and condition factor variations of Boleophthalmus boddarti in the Mekong delta, Vietnam