The bottomside parameters &amp;lt;i&amp;gt;B0&amp;lt;/i&amp;gt;, &amp;lt;i&amp;gt;B1&amp;lt;/i&amp;gt; obtained from incoherent scatter measurements during a solar maximum and their comparisons with the IRI-2001 model

N K Sethi,K K Mahajan

doi:10.5194/angeo-20-817-2002

The bottomside parameters &lt;i&gt;B0&lt;/i&gt;, &lt;i&gt;B1&lt;/i&gt; obtained from incoherent scatter measurements during a solar maximum and their comparisons with the IRI-2001 model

N K Sethi, K K Mahajan

Open Access

https://doi.org/10.5194/angeo-20-817-2002

Copy DOI

Journal: Annales Geophysicae	Publication Date: Jun 30, 2002
Citations: 33	License type: CC BY 3.0

Affiliation: CSIR National Physical Laboratory of India

Abstract

Abstract. High resolution electron density profiles (Ne) measured with the Arecibo (18.4 N, 66.7 W), Incoherent Scatter radar (I. S.) are used to obtain the bottomside shape parameters B0, B1 for a solar maximum period (1989–90). Median values of these parameters are compared with those obtained from the IRI-2001 model. It is observed that during summer, the IRI values agree fairly well with the Arecibo values, though the numbers are somewhat larger during the daytime. Discrepancies occur during winter and equinox, when the IRI underestimates B0 for the local times from about 12:00 LT to about 20:00 LT. Furthermore, the IRI model tends to generally overestimate B1 at all local times. At Arecibo, B0 increases by about 50%, and B1 decreases by about 30% from solar minimum to solar maximum.Key words. Ionosphere (equational ionosphere; modeling and forecasting)

Highlights

The International Reference Ionosphere (IRI) is a global empirical model which specifies the monthly average of the electron density, electron temperature, ion temperature and ion composition
Over the years, testing and modification of IRI has continued with extensive participation by a joint working group of the International Union of Radio Science (URSI) and the Committee on Space Research (COSPAR)
A comparison of Ne profiles derived from ionogram at low-latitudes during solar minimum and maximum periods, with those obtained from IRI-90, showed similar results (De Gonzalez 1996; Aggarwal et al, 1996)

Summary

Introduction

The International Reference Ionosphere (IRI) is a global empirical model which specifies the monthly average of the electron density, electron temperature, ion temperature and ion composition. Showed that B0 values based on Gulyaeva’s 1987 model were significantly larger, especially during daytime, for summer and equinox seasons, than those obtained from the measurements. Pandey and Sethi (1996), using I.S. measurements during daytime from Arecibo, for the solar minimum period (1974–1977), showed that the IRI-90 values of electron densities below the F2 peak at all the heights were larger during summer and equinox months.

Results

Conclusion