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> > Thanks for the update, and I think you summarized the problem correctly. > > Can you give me examples of the other meteorological visualization > packages that plot the wind barbs that way? Every reference that we > found for the WMO standard is to plot winds less than 3 kt as a barb > with no flags rather than as a circle. > > - Becky > I think this one is done and I am closing this ticket Yuan > > On 9/29/2011 11:18 AM, Unidata IDV Support wrote: > > Dear Becky, > > > > This thread is getting rather long, so just for clarification, as far as I > > can tell, wind barbs are plotted consistently between the plan view and the > > time series plots. Let me know if you see otherwise. > > > > On the issue of low-speed winds, wind barbs have been plotted in the IDV > > plan view in this fashion for ~10 years. Therefore, I am reluctant to make > > any changes without very good reason. I believe the IDV wind barbs are > > consistent with other meteorological visualization packages. > > > > Best Regards, > > Unidata IDV Support > > > >> > >> > >> > >> > >> > >> Hello again! > >> > >> Here's one more that I sent a few weeks ago, but haven't seen a > >> response. Julien did some initial work to get the layer controls > >> and main display plotting the same, but our testers have found that > >> the WMO standard is to plot winds less than 3 kt as a barb with no > >> flags rather than a circle. Have you had a chance to look into > >> it > >> again? > >> > >> Thanks! > >> Becky > >> > >> On 9/7/2011 2:06 PM, McIDAS Help Desk wrote: > >> > >> > >> > >> Can you update us on the status of this ticket? It's more of a > >> standard for winds less than 3kts to be plotted as a barb with no > >> flags, but now it's plotted as a circle. Can you switch it so > >> that both the layer controls and main display plot these as a barb > >> with no flags? > >> > >> > >> > >> > >> > >> > >> -------- Original Message -------- > >> > >> > >> > >> Subject: > >> > >> > >> Re: [IDV #RVK-621478]: McIDAS-V inquiry #1048 updated > >> > >> > >> Date: > >> > >> Fri, 05 Aug 2011 09:14:36 -0500 > >> > >> > >> From: > >> > >> Bob Carp<address@hidden> > >> > >> > >> To: > >> address@hidden > >> > >> > >> CC: > >> address@hidden > >> > >> > >> > >> > >> > >> Hi - > >> > >> Sorry for the delayed response. I was looking into this issue myself, > >> and I have found a few reliable sources that state that wind barbs for > >> winds of less than 3kts are plotted as a barb with no flags. Below are > >> some of the places I saw that reference this: > >> > >> Training course from the United States Navy (page 165 in the chart) > >> http://www.hnsa.org/doc/pdf/aerographer1.pdf > >> > >> Applied Atmospheric Dynamics (Text book, pages 7 - 8) > >> http://books.google.com/books?id=7IsmskcU3msC&pg=PA7&lpg=PA7&dq=wind+barb+1kt+wind&source=bl&ots=5sazNCEaT-&sig=V58M9VOKCKeDrTY8liAyTP89Dco&hl=en&ei=4hUwTvr0MYiwsAKF4KBZ&sa=X&oi=book_result&ct=result&resnum=4&ved=0CC0Q6AEwAw#v=onepage&q=wind%20barb%201kt%20wind&f=false > >> > >> University of Washington > >> http://www.atmos.washington.edu/mm5rt/descript/definitions/windbarbs.html > >> > >> MAV MOS wind barbs from the NWS shows barbs without any flags on them > >> http://www.nws.noaa.gov/mdl/forecast/graphics/MAV/MAV.BRBK_000.html > >> > >> Thanks > >> Bob > >> > >> On 7/28/2011 2:15 PM, Unidata IDV Support wrote: > >> > Bob, > >> > > >> > The wind barbs are now consistent between plots and views. Please get > >> the nightly build tomorrow to confirm. > >> > > >> > Best Regards, > >> > > >> > -Unidata IDV Support > >> > > >> >> Bob, > >> >> > >> >> I could be wrong, but here is my analysis of the situation which > >> is backwards from yours. > >> >> > >> >> First off, people appear to deal with wind barbs in knots rather > >> than meters per second. > >> >> > >> >> Second, my understanding is that wind speeds from 0 to 5 knots > >> are calm represented by a circle. After that, (i.e.>= 5 knots), we > >> start to see lines with barbs attached. The map view wind barbs, rendered > >> with VisAD, seem to do this correctly. Strictly speaking, as far as I can > >> tell, there is no wind barb line without a barb. > >> >> > >> >> In conclusion, I think the Map View of wind barbs are correct, > >> but the Dashboard Plot does not deal with calm wind speeds correctly. I > >> would recommend fixing the Dashboard plots of wind barbs for low wind > >> speeds. > >> >> > >> >> Best Regards, > >> >> > >> >> -Unidata IDV Support > >> >> > >> >>> While in most cases this problem appears to be fixed, there > >> is still an issue when a station is reading 1 m/s wind. When this is the > >> case, the plot in the Main Display Window shows an open circle, while the > >> plot in the Layer Controls (Displays) tab displays a barb without any > >> flags. However, the barb in the Layer Controls (Displays) tab does point > >> the proper direction with respect to the wind direction reported. > >> >>> > >> >>> This is a case where the barb is plotted correctly in the > >> Layer Controls (Displays) tab and not in the Main Display Window. This is > >> the only circumstance where I could find any inconsistency between the two > >> displays. > >> >>> > >> >>> ----==== Inquiry ====---- > >> >>> 1048 > >> >>> > >> >>> ----==== Summary ====---- > >> >>> Point data wind barbs differ between map display and plot in > >> layer controls > >> >>> > >> >>> > >> >>> > >> ################################################################################ > >> >>> > >> >>> http://dcdbs.ssec.wisc.edu/inquiry-v/index.php?inquiry=1048 > >> >>> > >> >>> > >> > > >> > Ticket Details > >> > =================== > >> > Ticket ID: RVK-621478 > >> > Department: Support IDV > >> > Priority: Normal > >> > Status: Closed > >> > > >> > >> > >> > >> > >> > >> > >> > >> > > > > Ticket Details > > =================== > > Ticket ID: RVK-621478 > > Department: Support IDV > > Priority: Critical > > Status: Closed > > > > Ticket Details =================== Ticket ID: RVK-621478 Department: Support IDV Priority: Critical Status: Closed