> Hi Yuan,Thank you so much for your reply. As usual, you are always able to > answer any question I have! The "Aggregate Grids by Time" option worked like > a charm for the MERRA-2 dataset. However, the aggregate grids by time option > won't work with the NASA GPM data. Below is the XML file for daily GPM > precipitation data: > https://gpm1.gesdisc.eosdis.nasa.gov/opendap/GPM_L3/GPM_3IMERGDL.05/catalog.xml Hi Teddy, The dataset in the NASA GPM data has no time dimension, and this is why you can not use the "Aggregate Grids by Time" option to deal with it. The easiest way is to ask the dataset server side to make a few changes to provide FMRC colleection for this collection. For you, the only thing you can do is to write an ncml to do the aggregation, attached is an example. Basically, the ncml create a time variable, and then use the variable to do the aggregation. Let me know if you have any question to understand this ncml file. > > I can read in individual dates, but I prefer to aggregate a series of dates. > I get an error when I try to select multiple dates and aggregate them by > time. Do you have the same error? Since it works with MERRA-2 and not with > GPM, I wonder if it has something to do with the GPM data structure itself. > Any ideas? > > As for myself, I continue to be a strong advocate for IDV throughout the > Caribbean. I have been living in Barbados for the past 3 years working with > both the IRI and the CIMH, but recently have started a 1 year contractor > position with the CIMH. As part of my duties I teach regional meteorological > forecasters at the CIMH. My classes are weighted heavily towards using IDV > and I can say that in 100% of my experiences that every student recognizes > the value of IDV. It is not uncommon for students to remain after class for > up to 30 minutes just to go into more depth and examples with IDV. Some > students are even petitioning to develop an IDV specific class. Kathy-Ann > Caesar, head meteorologist at the CIMH, also integrates the IDV into her > teaching. She is trying to integrate IDV into the courses on a more official > basis. Luckily, through your support in Colorado and through Brian Mapes, I > have developed a reputation around the region as the IDV guy. Just last week > I held a mini- workshop for regional climatologists at the 2018 dry season CariCOF meeting. Representatives from Guyana and Trinidad are organizing to host a weekly IDV class for me to lead. Tons of untapped opportunity matched with very high interest. > One of my goals is to write an IDV users manual that focuses on the needs of > developing met services. It would not be for operations, but instead would be > for diagnostics, case studies, and other climatological applications. I > welcome any ideas or your initial reactions. Love to hear this kind of story. Thanks for promoting the IDV in the Caribbean and will provide any help you need. Yuan > Please tell Julian and Tom that I said hello. I look forward to an even > greater year of IDV productivity in 2019. > Thank you for your continued support. No rush to reply. teddy > > > http://www.teddyallen.com > > "To move quickly, go alone. To move far, go together." > > African Proverb > > > On Tuesday, November 27, 2018, 6:47:36 PM AST, Unidata IDV Support > <address@hidden> wrote: > > > Hello IDV gurus, > > > > I would like to be able to access MERRA-2 data via opendap. > > > > I have followed the guidelines given in this thread: > > > > https://www.unidata.ucar.edu/mailing_lists/archives/idvusers/2017/msg00001.html > > > > and opened the following file in the catalogs section: > > > > https://goldsmr5.gesdisc.eosdis.nasa.gov/opendap/MERRA2/M2I3NPASM.5.12.4/catalog.xml > > > > However, when I do the above, I am limited to access only the times > > given per individual .nc file. I would prefer to be able to select times > > across multiple .nc files from the times section in the field selector > > tab. Essentially, each .nc file is opened as an individual data source > > whereas I would prefer to have all .nc files concatenated in time so > > that I can select across all times in the field selector. > > Hi Teddy, > > Good to hear from you, it has been a while. > > You should be able to select multiple files from the Data Chooser > Catalog, > you can open > each tree, and select what you want with the shift key or ctrl key. The > important thing is > to specify the "Data Source Type" as "Aggregate Grids by Time", then Add > source,..... > > It would be nice if you can provide more information of IDV usage in the > Caribbean region. I would > love to provide any help you needed. > > Sorry for a little delay as I was traveling in the Thanksgiving break. > > > Yuan > > > > The alternative is to use the URL option in the Data Choosers tab. I can > > access MERRA-2 across all times when I enter the below address in the URL > > option: > > > > dods://goldsmr4.gesdisc.eosdis.nasa.gov/dods/M2I1NXASM > > > > But there is a lag between most recent data and what is available from the > > URL address. The catalog option has almost no lag in data availability. Is > > there a way to read in the catalog file so that all times can be selected > > in a similar way to time selection for the URL section so that I can > > acce ss most recent data across multiple .nc files? > > > > A more general question is, what is the difference > > (advantages/disadvantages) between data access through URL or Catalog? > > URL is a individual file (at least logically) and the Catalog is the pointer > to multiple files in > the server. > > > > I hope all is well. We continue to use the IDV in training and classes in > > the Caribbean. I have integrated the IDV into training at The Caribbean > > Institute for Meteorology and Hydrology and even use it for class work at > > The University of the West Indies. It is always very well received. Keep > > up the great work. > > > > Thank you,teddy > > > > http://www.teddyallen.com > > > > "To move quickly, go alone. To move far, go together." > > > > African Proverb > > > > > > > > > Ticket Details > =================== > Ticket ID: DZF-714003 > Department: Support IDV > Priority: Normal > Status: Open > =================== > NOTE: All email exchanges with Unidata User Support are recorded in the > Unidata inquiry tracking system and then made publicly available through the > web. If you do not want to have your interactions made available in this > way, you must let us know in each email you send to us. > > > > Ticket Details =================== Ticket ID: DZF-714003 Department: Support IDV Priority: Normal Status: Open =================== NOTE: All email exchanges with Unidata User Support are recorded in the Unidata inquiry tracking system and then made publicly available through the web. If you do not want to have your interactions made available in this way, you must let us know in each email you send to us.
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