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Topic: Date inaccuracies in records

There are still many thousands of records on the NBN atlas with dates that have been migrated incorrectly from the old Gateway. The thread started by Jim here https://forums.nbn.org.uk/viewtopic.php?id=6803 explains about the records with years and year ranges being incorrectly given precise dates of 01/01/XXXX. I think some of these have been corrected, but there are still many incorrect dates, presumably relating to day ranges, and month ranges.

See example here, which was a day range record for 01/01/2010-31/12/2010 that has been allocated to the 1st January:
https://records.nbnatlas.org/occurrence … d607c84587

A quick examination of any summer species (e.g. Orange-tip) will show similarly that there are still many thousands of January records - https://species.nbnatlas.org/species/NH … 86#records

If people are to use and rely on these data for important decision making purposes or for scientific investigation these issues need to be sorted ASAP.

MARK

Mark Pollitt
SWSEIC (formerly DGERC)

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Re: Date inaccuracies in records

A typical good BRC printed atlas will contain both a map and a phenology chart. The Atlas needs to be at least as good as that, unreliability on one of the basic four Ws is not acceptable.
It is likely that this issue is a factor affecting many potential uploads, compilers of millions of records awaiting a resolution.

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Re: Date inaccuracies in records

Darwyn Sumner wrote:

It is likely that this issue is a factor affecting many potential uploads, compilers of millions of records awaiting a resolution.

Just in case it helps, this is one of the reasons why we haven't uploaded any data yet.

Charlie Barnes
Information Officer
Greater Lincolnshire Nature Partnership

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Re: Date inaccuracies in records

Thank you for highlighting this. The Atlas does store the precision of the date, i.e. to the year, month or day. However, the graphs on the species pages do not take into account the precision of the date. I have raised this as a error and will write a reply once it has been resolved.

Thanks, Sophie

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Re: Date inaccuracies in records

I can't check this as the "original vs processed" button appears to have disappeared but I believe because the date range was supplied in two fields rather than one, the system doesn't know it's a date range and takes the first date as "the" one (this is corroborated by downloading the record - only the first date is provided as "the date").

As Mark says, this is likely to only occur with NBN Gateway format uploads/transfers because that's how the Gateway worked (two dates, even if they were the same). Darwin Core has a single date field, regardless of the date precision.

I would hope the ALA system is clever enough that if a date covered e.g. multiple months, it would not include it in e.g. the phenology charts, but would include it in e.g. the yearly charts.

Charlie Barnes
Information Officer
Greater Lincolnshire Nature Partnership

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Re: Date inaccuracies in records

The Atlas does store the start and end date and I will check why the downloads only include the first date. It does look like there is a problem with the phenology charts and I will get that resolved as soon as possible.

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Re: Date inaccuracies in records

We have reprocessed all the records in the Atlas to correct the date precision based on the start and end dates. For the majority of cases this has correctly identified vague dates and displays the dates correctly, i.e. just the year, the month and year or the full date. This means that we have far fewer 'January' records.

We still have a problem with year ranges. Our developer is looking into this now. The github issue for this is here:https://github.com/nbnuk/nbnatlas-issues/issues/399

Please do let me know if you see any other problems with the dates in the Atlas.

Many thanks, Sophie