id	summary	reporter	owner	description	type	status	priority	milestone	component	version	resolution	keywords	cc
344	ROPP and L2 handling	Ian Culverwell	Stig Syndergaard	"KBL writes:

{{{

Hi Ian

I have reviewed the paper by Wang et al, submitted to JGR, where they compare
ROPP against CDAAC processing of some COSMIC data. They looked at: Input data
set: ~20000 COSMIC profiles over the Australian region from 2010 CDAAC: Data
version v2010.2640 (produced by CDAAC 3.0) ROPP: ROPP-6.0 processing from CDAAC
phases to atm and dry quantities

Their results show rather large differences, much larger than what was reported
in Gorbunov et al (JTECH 2011) and Lewis' GSR-13 (2010), between CDAAC and ROPP
data so I think they must have done something wrong (maybe related to mixing
different height coordinates...). This is part of my report: ""Fig. 6 in the
present manuscript shows a large bias between CDAAC and ROPP in disagreement
with the previous investigations. This bias is linearly increasing over the full
height range and, furthermore, has a different sign for bending angles and
refractivities which does not agree with the (naive) expectation that the sign
of this bias cannot change under the Abel transform (which links these two
quantities). The reason for this different behavior is not explained and this
should be further investigated and characterized before this manuscript can be
published. I therefore ask the authors to revise their manuscript before I can
recommend publication.""

However, in their paper they also show one example of a profile (""event 2"")
which is treated different regarding the L2 smoothing in the CDAAC and ROPP
processing. This is the one in Fig. 2 (see attached file). This is also shown in
Fig. 3, together with ""event 1"" (which is a rising example). The retrieved
quantities for event 1 and 2 are shown in Fig. 4. 

I discussed this issue with Stig and we think that this case (event 2) should be
checked more carefully since maybe the way ROPP treats this case is not so good
(or maybe it is ok, but it has to be checked). Please raise a ROPP ticket
related to this and assign it to the next release. This issue may be linked to
one of the things Stig has on his list of ""ROPP issues"" so he will probably be
discussing this further with you.

Thank you
Kent

}}}

"	task	accepted	normal	DMI ROPP developments	ropp_pp	7.0		CDAAC, ROPP