HAO 2011 Profiles In Science: I-Te Lee

Contact:

303-494-1513
ite@ucar.edu

I-Te Lee is a Graduate Research Assistant at the High Altitude Observatory (HAO), National Center for Atmospheric Research (NCAR). He is currently studying the data assimilation by using NCAR TIE-GCM and FORMOSAT-3/COSMIC radio occultation data. His research interests include the ionospheric density structure of mid- and low- latitude.

Publications

(1) Lee, I T., W. Wang , J. Y. Liu, C. Y. Chen, C. H. Lin. The ionospheric mid-latitude trough observed by FORMOSAT-3/COSMIC during solar minimum.

Abstract: This paper is the first time to report global structures of the ionospheric mid-latitude trough using electron density profiles derived from the GPS radio occultation experiment on board FORMOSAT-3/COSMIC satellites during the solar minimum period, February 2008–January 2009. Results show that the mid-latitude trough extends from dusk to dawn in all four seasons, and is most pronounced in the winter hemisphere. The troughs in the two hemispheres are asymmetric, where the trough in the northern hemisphere is more evident and stronger than that in the southern hemisphere during the equinoctial seasons. In general, the trough minimum position shows a high-low-high latitudinal variation with magnetic local time and to occur at lower latitudes under higher magnetic activity. In addition, the mid-latitude trough structures become more complex in the southern hemisphere, which is the result of the nighttime plasma density enhancement of WSA.

Figure 1 caption: The seasonal-averaged pseudo-3D images of the F2 peak density map (log10 (Ne), cm-3) from Feb. 2008 to Jan. 2009 in magnetic polar coordinates for the March equinox, June solstice, September equinox and December solstice. The inner and outer perimeters are 80° and 30° in magnetic latitude. The left and right columns are results in the northern and southern hemisphere, respectively. The numbers around each plot give the geomagnetic local time.