Altitude on observations

I’ve recently been confirming some identifications for moths that are found in mountains (new for me). Is there any way to include altitude in observations? Some moths, and I presume other life forms, are found at a specific altitude. Or should this be added into the “comments” part of the observations?

There are a number of altitude observation fields that you could add:
https://inaturalist.org/observation_fields?utf8=✓&q=altitude&commit=Search

or perhaps more properly altitude above sea level or elevation:
https://www.inaturalist.org/observation_fields?utf8=✓&q=elevation&commit=Search

Might be useful. I don’t see how anyone could use them to easily search for or select observations in a certain altitude range though.

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Altitude is also helpful in determining some odonate identifications. It would be nice if there were some standard method of listing a value that as searchable as the Annotations for this data.

As @tony_willis mentioned it seems unwieldy from the user’s end to use Observation Fields and using comments might be a bit too inconsistent.

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I would vote for this feature if it were searchable just from the location on the observation. Since I can see the elevation on the observation through the map, couldn’t that be searchable somehow?

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I know this is a bit of a tangent, but I would request some precise distinction between altitude and elevation if you’re adding fields or search functions. I had more than one professor that would ding students hard for loose application of those terms, so it was beat into me pretty successfully:

Altitude: vertical distance between an object and the local surface of the Earth.

Elevation: vertical distance between the local surface of the Earth and global sea level.

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it’s worth nothing that it would be neat for iNat to be able to automatically calculate elevation of points, but at the current time it isn’t likely to be feasible, one needs a Digital Elevation Model to do this and i don’t think that is consistently available globally. It may also add a lot of processing time. You can see the topos on the maps though they may not always be right and make sure to check your units for feet vs meters

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GPS data in Exif often contains elevation. You could get a lot of elevation data just by parsing that.

It’s a fairly useful thing to have; some of the plant databases out there like CalFlora are searchable by elevation range.

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I thought that apples photos the ones taken
With a iPhone had that data embedded on the photos already

i don’t think so, are they? If so i agree it would be neat to display, even if not very precise, could be used for data stuff

I can think of a couple of high-resolution, global DEMs, so that in itself is not an insurmountable problem. Might be easier from the developers’ perspective if there was a pre-existing web service they could query for elevation at a specific location. Google and ESRI would be the most obvious potential providers, but I’m not familiar enough with that space to know if such services are available.

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Yes, the iPhone does record altitude. You can see it on one of my photos https://www.inaturalist.org/photos/32817612 (GPS altitude 66.0). You can also see it one one that I geotagged from a Garmin Dakota 20: https://www.inaturalist.org/photos/33363436 (GPS altitude 1003.75). Though in neither case did it record the unit of measure (metres in these 2). When submitting geotagged images it could simply be recorded in the same way as latitude and longitude.

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Thanks for making that distinction. Having lived on the flat lands (Wpg. MB) most of my life, altitude or elevation is almost meaningless! For most organisms west and east of me, elevation is almost meaningless. But apparently some moths in the mountains are found around a certain altitude e.i.at the treeline.

To be clear, these are not my identifications - I was confirming ID’s. It’s just that some of the moths are found at (or below) certain elevations, and having that info may have helped the identification/confirmation process.

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Elevation is a standard thing that every GPS chip calculates. I’ve seen it show up in the Exif for devices from multiple vendors, and the bulk of my uploads actually have it.

Look for the ‘GPS altitude’ field, which tends to actually record elevation. You can probably go back and add elevation to most existing observations.

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@mamestraconfigurata do you have a specific feature request here, or are you asking about the best way to add altitude data to iNat observations?

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I would like to suggest this be added to the Feature Request…

"Can we have the option in the uploader to extract the exif elevation data and have it incorporated into the observation, in a similar field as the Acc (m) field…"

I would imagine it handled in a similar way as the Acc (m) field, and that it would be null by default, and the option in the uploader would default to not extracting it.
I actually got excited when I first saw the Acc (m) field in the identify page panel, as I thought it read “Alt (m)” and that iNat had incorporated elevation into the observations!

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It should be here next to the longitude, before accuracy. I believe the latitude and longitude are taken from the first photo’s metadata so just extract the elevation as well or if it does not exist leave it blank.

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Just keep in mind that GPS elevations are always less accurate than their horizontal coordinates, generally by a factor of 3 or more. If we start capturing elevation (which I am in favor of), “Accuracy” should be re-labeled as “Horizontal Accuracy.” I don’t believe GPS chipsets capture any kind of vertical accuracy, but correct me if I’m wrong.

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wait… does it actually measure the altitude in relation to the satelites it is measuring off, or does it look up GPS coords to get the elevation in the same way many mapping apps do? In other words, how does it know where MSL is?

My understanding is that GPS chipsets base elevation/altitude solely on calculations directly from satellite signals and geometry, and the reference ellipsoid model in use, not from looking up horizontal coordinates against a Digital Elevation Model like some mapping apps. The height above (or below) the ellipsoid will not always correspond exactly to local MSL.

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