Comment on “Initial results from SKiYMET meteor radar at Thumba (8.5°N, 77°E): 1. Comparison of wind measurements with MF spaced antenna radar system” by Karanam Kishore Kumar et al.

Meteor radar measurements of MLT winds near the equatorial electro jet region over Thumba (8.5° N, 77° E): comparison with TIDI observations

“…We take the advantage of these studies to compare the TIDI derived composite diurnal variation of zonal and meridional winds with meteor radar observations. We limit to compare the diurnal pattern in zonal winds as these measurements were recently debated (Dhanya and Gurubaran, 2009). As mentioned earlier our aim is to justify the MR observed westward motions at 98 km during local noon time.…”

“…However, in recent years, there has been some debate on the reliability of the winds measured by the meteor radar at the 98 km height region (the maximum height where we obtain continuous data from the meteor radar at Thumba) as Thumba is located in the vicinity of the magnetic dip equator where there is a presence of the equatorial electrojet (EEJ), a strong zonally flowing current system which peaks around 105 km over the magnetic equator (Kumar et al, 2007b(Kumar et al, , 2009Dhanya and Gurubaran, 2009). The debate was started by Dhanya and Gurubaran (2009) and the important aspect of their query is the scattering of radio waves by the irregularities that grow on the meteor trail as a result of plasma instabilities induced by EEJ. Kumar et al (2009) based on earlier studies argued that the echoes from such irregularities are non-specular, which will not have any outstanding implications in MR measurements as reported by Chapin and Kudeki (1994).…”

Reply to comment by R. Dhanya and S. Gurubaran on “Initial results from SKiYMET meteor radar at Thumba (8.5°N, 77°E): 1. Comparison of wind measurements with MF spaced antenna radar system”

“…We have not carried out any analysis to substantiate this point and it was solely based on the results by Gurubaran and Rajaram [2000]. Now, we will discuss the questions raised by DG09 in the following section.…”

“…The authors found a large zonal wind difference between the meteor and MF radar wind measurements during the local daytime and the difference was attributed to the contamination of MF radar measured winds with EEJ induced drifts. Now, Dhanya and Gurubaran [2009] (hereafter referred to as DG09) question the validity of this interpretation and state that there is a ‘basic flaw’ in this approach. Before discussing the questions posed by DG09, we are stating that our approach was very simple and logical.…”

“…Now, Dhanya and Gurubaran [2009] (hereafter referred to as DG09) question the validity of this interpretation and state that there is a ‘basic flaw’ in this approach. Before discussing the questions posed by DG09, we are stating that our approach was very simple and logical. We found large discrepancy in the zonal winds measured by meteor and MF radar during the local daytime and were looking for a possible explanation.…”