Re: CALIPSO L2 data - Help

[Peter K. <pet...@fa...>]

Hi Thaize,

Great to hear you find ccplot useful.

The rows and columns of Integrated_Attenuated_Backscatter_532 in the
layer product mean profile number and layer number, i.e. there can be up
to e.g. 10 layers detected in each individual vertical profile. The
actual number of identified layers is stored in Number_Layers_Found (the
remaining layers are filled with -9999.0. Latitude and Longitude contain
3 values per profile in the 5 km products:

1) latitude/longitude the first pulse included in the 15 shot average
2) the footprint latitude/longitude at the temporal midpoint (i.e., at
the 8th of 15 consecutive laser shots)
3) the footprint latitude/longitude for the final pulse

See CALIPSO Quality Statements Lidar Level 2 Cloud and Aerosol Layer
Products, page 3
(https://eosweb.larc.nasa.gov/PRODOCS/calipso/Quality_Summaries/CALIOP_L2LayerProducts_3.01.html).

Layer_Base_Altitude and Layer_Top_Altitude contain layer base and top
altitude corresponding to layers in
Integrated_Attenuated_Backscatter_532 (by column).

I hope this answers your question. Good luck with your analysis! Let me
know if you have any more questions.

Peter

On 23/11/17 00:16, BARONI, THAIZE wrote:
> Hello there!
> 
> My name is Thaize and I'm a PhD student from NUIG, Ireland
> I'm part of the C-CAPS group and currently, I'm working with CALIPSO data
> I found ccplot and used it at the very beginning of my PhD... it was
> really useful! 
> However now, I have to do some plots on my own and I'm kind of stuck
> I don't really have any question about ccplot, but about CALIPSO data
> itself (L2 especially)
> Could you help me, please? 
> I don't know very well how to read and interpret CALIOP L2 Integrated
> Attenuated Backscatter data...I mean, the data itself (the rows and
> columns) 
> I read the CALIPSO documentation several times but I still don't
> understand how it works...Could you please explain it to me?
> The dimensions (number of columns and rows) between lat/lon, Integrated
> Attenuated Backscatter 532/1064 and Altitude, for example, are different
> and I don't get why
> This doesn't happen with L1 and L1.5 data...
> I'm sorry if this is a basic question and it's not directly related
> with ccplot, but as I said, I'm struggling with it for ages now. I'd
> really appreciate any help or explanation you could provide!
> 
> Thank you very much for your attention
> 
> Cheers
> 
> Thaize