The US National Space Weather Program (NSWP) refers “Space Weather” to “conditions <br />
on the Sun and in the solar wind, magnetosphere, ionosphere, and thermosphere that can <br />
influence the performance and reliability of space-borne and ground-based technological <br />
systems and can endanger human life or health.” <br />
One of the basic research areas that were specified to have significant gaps in our <br />
present understanding and represent particular challenges in achieving Space Weather <br />
goals is forecast of the evolution of ionospheric irregularities. <br />
The nighttime electron density irregularities in the low-latitude F region cause <br />
the most severe radio scintillation affecting the satellite communication and <br />
navigation systems. Understanding of the onset conditions of the irregularities and <br />
forecasting of this phenomenon have been the top research priority since its discovery. <br />
While the electron density irregularities are known to be produced by the Rayleigh-Taylor <br />
instability, the day-to-day variability of their occurrence and dependence on the <br />
longitude, season, solar cycle, and magnetic activity were not yet clearly understood. <br />
In this talk, we will overview the characteristics of the low-latitude ionospheric <br />
turbulence and discuss the recent progresses and future work.