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>From: David Garrana Coelho <address@hidden> >Organization: UFRJ >Keywords: 200305280404.h4S44lLd024244 Hi David, re: Currently, 5 images sectors centered on 23S, 53W are being created on brisa (from ADDE access > I dont know if 53W was a typo or intended, but I suppose its the >furthest east you could center the image, am I wrong? If I am, 43W would >be more appropriate.=) (More comments on this below) I chose the center point so that the areal extent of the images at their maximum resolution would not include blank space on the eastern flank. After I get you some HOWTOs for bringing up McIDAS and loading the full images yourself, you will see that the GOES-12 scans I chose go as far east as possible, and so cover your modeling domain as well as can be hoped for. 0.65 um (visible) - resolution - 1 km: http://www.unidata.ucar.edu/staff/tom/meteoforum/sectors/goeseast_vis_resolution.gif 0.65 um (visible) - area coverage - 2 km: http://www.unidata.ucar.edu/staff/tom/meteoforum/sectors/goeseast_vis_extent.gif 3.9 um (short infrared) - area coverage/resolution - 4 km: http://www.unidata.ucar.edu/staff/tom/meteoforum/sectors/goeseast_39_resolution.gif 6.5 um (water vapor) - area coverage/resolution - 4 km: http://www.unidata.ucar.edu/staff/tom/meteoforum/sectors/goeseast_wv_resolution.gif 10.7 um (thermal infrared) - area coverage/resolution - 4 km: http://www.unidata.ucar.edu/staff/tom/meteoforum/sectors/goeseast_ir_resolution.gif 13.3 um (long infrared/CO2) - area coverage/resolution - 4 km: http://www.unidata.ucar.edu/staff/tom/meteoforum/sectors/goeseast_co2_resolution.gif > The links above aren't working, Oops! I was frantically typing the message yesterday afternoon while trying to get out of the office as soon as possible. The 'gifs' directory is where I normally put images for remote users to look at. I put the new sectors in the meteoforum/sectors directory. The URLs as listed above should now be correct. I verified the display of the CO2 image on my home machine (through a 24K dial-up, ugh!). Sorry for the typo! >but I tried mcidasx on brisa from >home (bashing my head against the monitor a few times trying to discover >the right commands to display the imagery...lol), and it appears to be >cutting exactly Rio de Janeiro state...:=/. When there is no southern sector from GOES, you will end up with either of two situations: - Northern Hemisphere scan which extends just south of Belem - Northern Hemisphere extended scan which extends to RJ >The way it is, it display a >large portion of central south america, including the Andes and a part of >Pacific Coast. Rio de Janeiro is exactly off the eastern frontier of >image. This may be caused by your McIDAS session having small frame sizes (the default is 480x640) and you loading the image in the default manner which puts the upper left corner of the image in the upper left corner of the display frame. Try the following: 1) start McIDAS with: mcidas -config 2) from the GUI that pops up, set the frame sizes to 700x950. This will be done by dragging the slider for the number of Lines and Elements from left to right 3) click on the save options radio button near the bottom of the GUI 4) start your McIDAS session After you have a session up with the MCGUI interface, click on the Display option at the top of the MCGUI; select imagery, and then select the RIO dataset. If the RIO option doesn't show up (this is what I was trying to setup yesterday afternoon, and it may not be finished), then select the GOESEAST dataset. GOESEAST will allow you to display sectors from the images from which the RIO sectors are being created. This is the the point I wanted to get you to anyway, so let's go for it now. When you are able to get the GUI selector up for the RIO and/or GOESEAST datasets, you will be able to select the band, center Lat and Lon for image loads of the latest image, and do a 10 frame loop. At this point, you will be able to see the full extent of the sectors and/or full images from GOESEAST. >Don't know if it helps you, but to give a visual cue, Rio is >exactly on the single portion of Brazilian coast which is oriented mostly >east-west, with 2 small bays along it. The good news is that McIDAS knows where RIO is and so can move the cursor to it. The disconnect we are seeing at the moment is undoubtedly being caused from you not being able to see the full extent of the sectors being created, or your having looked at an image for which there was no southern GOES-12 sector to composite. >I also tried to open the files >using the "xview" command, and it showed a missing eastern part of image >misplaced at the west side of image (which mcidas was unable to show). It >looks like a cut/paste operation made out of order (my guess). I will check on this, but I don't think that this is the case. I would bet that xview is not correctly handling the imagery which is in McIDAS AREA format. re: let's put off the generation of full South American sectors until we decide on the Rio sectors >Okidoki I was thinking about this last night at home, and I think that you have plenty of bandwidth to grab the full South American portion of the larger images for all of the IR channels. The full images are only 4.4 MB in size, so this should not be hard. With the full South American view, you can create any sector you want using McIDAS. The visible image, on the other hand, is pretty large, 69 MB, so creation of image sectors from it at full resolution is probably the way to go. You could, of course, create a VIS sector of all of South America at the same resolution (4 km) as the IR sectors and also create high resolution sectors for wherever you want. The script I setup for the transfer is easily modified to create any sector that you can imagine (to the extent of the original images, of course). > As I mentioned above, did my best to view the imagery. Nothing >very fancy as animations, of course, due to bandwidth limitation here on >my home. I have the same problem! I used to live in a place that had a spectacular DSL connection: 1.2 Mbps down and 320 Kbps up. That was heaven! By the way, since you are running Linux at home, you could load and run McIDAS from there. That way, the only thing going over the network connection is the data. If your connection is as slow as mine (24 Kbps), then loading images will be very painful. Displaying things like observational data is very useful, however. >I logged as mcidas and started mcidasx. After a lil head bashing, >I figured out DSINFO and IMGDISP, and saw the images. I tried MAP BRAZIL >and it looked somewhat distorted, maybe because of projection options, not >sure. To draw am map on top of an image, you use 'MAP SAT' or commands like 'MAP FILE=OUTLHRES'. These tell McIDAS to use the navigation information already contained in the image. A 'MAP BRAZIL' will draw a map of Brazil in a conic projection regardless of the image that is displayed. This is why the map did not look correct on the image you displayed. >Amidst my (blunt) learning process, I tried the GUI (without success >in loading/displaying any data on it) and executed mcinet2000.sh as root >(as told on MCIDAS Installation page), hope this was something you would >ask for me to do in the future, if not, my apologies. Actually yes, I was going to ask you to run mcinet2002.sh today so that I could load the images being created on brisa back on my machine at work. This was the final step in providing me with an end-to-end verification that the sectors being created were correct. Thanks! One thing you will need to do, however, is edit /etc/services as 'root' and comment the first entries for port 500 (isakmp). McIDAS incorrectly sets itself up to use port 500 for uncompressed data transfers. It uses port 503 for compressed data transfers, which is also incorrect. -- I say incorrect since they did not register the use of these ports with Iana -- In the future (perhaps the next distribution), they will use port 112, which has been registered with Iana for years (we did that back in the early 1990s). > I am planning to try the observational data overlay and map >options tomorrow, locally. The first step is to get the MCGUI up and running correctly. The next step is to explore the options available. > As a small side note (and something of heads up too) I was >thinking about submitting all this work you having as a paper in the next >Brazilian Congress of Meteorology in the next year. It would serve as an >open invitation to fellow institutions here in Brazil (and South America) >to use IDD, and as a small (very small compared to all the trouble you >having, may I add) "payment" for all the work you having with us. I was >thinking of something like a small report of all the work done on brisa >(and the future nameless dedicated server), history and the capabilities >of the tool, and "testimonies" of current users (UFRJ, Buenos Aires and >Belem). Let me know if you like the idea...:=) I think that this is a GREAT idea! To my mind, this is the only way that other Brazilian and South American universities will be come intimately familiar with the potential benefit of participating in the Unidata community. It has been my goal for almost 15 years to foster the growth of our scientific community in the international arena. I am absolutely delighted that the movement of data to your institution is working as well as it is. A short year and a half ago, doing what we are doing now was not possible, and now it is. You have got to love this :-) Hopefully, a presentation at the Brazilian Congress of Meteorology would get a number of institutions wanting to participate in IDD-Brazil. This would mean, of course, that the UFRJ IDD node and internet connection would become very busy :-) > Thanks once more, No worries. I have to close here so I can eat some breakfast and then head into work. Cheers, Tom -- +-----------------------------------------------------------------------------+ * Tom Yoksas UCAR Unidata Program * * (303) 497-8642 (last resort) P.O. Box 3000 * * address@hidden Boulder, CO 80307 * * Unidata WWW Service http://www.unidata.ucar.edu/* +-----------------------------------------------------------------------------+