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Cumulative Precipitation Data Problem!

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#1
RODEO

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Need help big time... can't find the solution to this problem, and we need it very much for help managing a current emergency response...

Problem: need cumulative precipitation for a given state, in this case Oklahoma, USA
data comes in a daily total, shapefile format
the problem is, the recording stations are not in the data unless precip was recorded...
this makes joining the data near impossible. I've tried work arounds using FULL JOINS in MS ACCESS, but it's too cumbersome to keep up on daily... I need a GIS solution...

Data:
http://www.srh.noaa....ip_download.php
this is US data, I'm clipping down to Oklahoma State
If any of you want to try this, grab some dates between 12/08/2007 - 12/15/2007

I've tried my best to find a GIS solution (merge, interesect, etc...) and can't figure this one out???

If you all can't help, I'll have to start programming a solution, not the way I want to do it - so you're help is gonna be well appreciated if ya'll can find a solution!

Thanks in advance, and Happy Holidays to all!

#2
frax

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I haven't looked at the data, but are the polygons different for each date or so? Maybe convert to grids?
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#3
RODEO

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I haven't looked at the data, but are the polygons different for each date or so? Maybe convert to grids?


Ah, should have made that clear - it point data - that's why I can do an intersect, intersect doesn't work on point data.....

thanks, keep it coming.... we need to do be able to do a daily update to the precip cumulative total, and we're not getting it done :blink:

#4
MapMedia

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What do you want to use this data for? Reason I ask is there are other, possibly better, data sources. Have you tried d/ling data from NCDC site or USDA/Oklahoma site?
There is also the PRISM 1960-1990 dataset.


I looked at Dec 8, 2007 from the NWS site you use. Not sure what you need, but if your date range is small (~30 days), you could create one big flat file in Excel then summarize by station id. Output dbf would have station ID, cumulative rainfall, and number of data points. Then import to GIS to run interpolation on points.

#5
RODEO

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What do you want to use this data for? Reason I ask is there are other, possibly better, data sources. Have you tried d/ling data from NCDC site or USDA/Oklahoma site?
There is also the PRISM 1960-1990 dataset.


I looked at Dec 8, 2007 from the NWS site you use. Not sure what you need, but if your date range is small (~30 days), you could create one big flat file in Excel then summarize by station id. Output dbf would have station ID, cumulative rainfall, and number of data points. Then import to GIS to run interpolation on points.



I'm looking at those alternative datasets now - I'll keep the fingers crossed. the PRISM doesn't cover the the data range we need (need current precip).

I used EXCEL for the last dataset, but there are 90,000+ records, so I have to break up the data a lot, and being I have to do it daily that's no good :(

what I'm trying to do is "merge" the points from various shapefiles from different dates, some with the same locations, some with different locations - and when they merge, get the precip field to either a) sum or B) go into seperate fields so I can do a sum...

I keep thinking there is a GIS solution. I know one project I did a long ways back did this in GRID - but I can't spend the time to try an recreate that from a distant memory...

going to have to try and program it this afternoon using PERL - not gonna be a fun afternoon :o :o

thanks again!

#6
graveldraw

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If I were doing this sort of thing, I would create a database table, then use perl to insert values from the *.dbf files. The data could be summarized by month into a grid/raster file. Using a database might be more efficient than using Excel or GIS solution, but then I have more skills in database than GIS. If you might be interested in someone helping, contact me at childress.dan {at} gmail.com.

Best,
Dan

#7
RODEO

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If I were doing this sort of thing, I would create a database table, then use perl to insert values from the *.dbf files. The data could be summarized by month into a grid/raster file. Using a database might be more efficient than using Excel or GIS solution, but then I have more skills in database than GIS. If you might be interested in someone helping, contact me at childress.dan {at} gmail.com.

Best,
Dan


Thanks! I'm leaving for the holiday! check back in soon!

#8
RODEO

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Thanks for all the help folks! I was mostly trying to ensure we hadn't missed an obvious GIS solution.....

In the end, I ended up programming this in PERL, not my favorite solution, but it did solve the problem!

If anyone ever comes across a solution in GIS, I'd love to know!




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