Hello Shaun,

your edits claims to be based on Bing imagery but Bing apparently has no coverage in this area. Could you explain the basis of this edit?

Hello ELadner,

has this change been discussed anywhere? It has been a long time consensus that the Caspian Sea is to be tagged as natural=coastline which is also documented on the wiki:

osm.wiki/Tag:natural%3Dcoastline

Changing that will require a broader discussion and should not happen without a broad agreement within the community.

Hello TACRfan,

what do you base this mapping on? Both tagging and geometries in large parts seem fairly implausible. Please no not perform fantasy mapping here.

Well - the 'how to map' section on the wiki does not represent common mapping practice here and contradicts the basic definition of natural=beach as a landform.

The wiki by the way currently also says you should tag the part of a beach below the high water line as natural=shoal - which of course does not make much sense.

I would be open to clarifying the wiki in either way but using your concept would both require a lot of change in mapping all over the world and would cause additional problems (like which part of the beach the name tag is to be applied to).

My main reason for messaging you here is to let you know that this size of change affects the coastline processing and you plan future changes accordingly.

Independent of that I cannot really recognize the idea behind the current position of the coastline, i.e. why it is there and not further upstream or downstream. The lowest parts of all these 'rivers' seem part of Chesapeake Bay, in particular what is mapped as Miles River here:

osm.org/relation/6840770

seems to be a side bay (Eastern Bay) with separate connections to the main bay in three directions (north, west and southwest) and likely dominated by tidal currents rather than river currents. But i am no expert in this area so this is up to you to assess.

I remember there was a discussion on talk-us some time ago if to take Chesapeake Bay out of the coastline. Removing all side bays makes less sense since you end up with a meaningless residual bay that mostly consists of vitual geometries (i.e. coastlines that do not actually represent the edge of a waterbody).

Hello Elliott,

please be aware that such large movement of the coastline interrupts coastline processing for the main map on osm.org. It would be advisable to perform such changes in a single edit after discussion in the local community.

To also consider here:
osm.wiki/Proposed_Features/Coastline-River_transit_placement

I would consider this essentially mapping for the renderer - beaches do extent below the high water line obviously and natural=tidal_beach is not documented while equivalent established tagging exists (natural=beach + tidal=yes)

If the lowest parts here is still a beach (i.e. wave formed) or a tidal flat i don't know of course.

There is a reverter plugin in JOSM that allows you to revert your changesets:

osm.wiki/JOSM/Plugins/Reverter

If the different changes modify the same features you need to make sure you revert them in reverse order, the latest one first. If you are unsure how to do this you can contact the data working group who are experienced with reverting larger edits:

osm.wiki/Data_working_group

Hello NolwennC,

Google Earth data may not be used as a source for mapping in OSM, please revert your edits based on that and in the future use only allowed sources - JOSM will offer you several well usable options for this area.

Yes, names can be established purely by remote use but still some broader recognition is required.

There are plenty of glaciers, fjords and lakes in this area by the way that are unnamed in OSM although they have well established names.

Hello fschmidt,
that does not qualify as a verifiable name in OSM, names should be practically used by people locally or by people visiting the area. Names invented by some remote interest community should not be be entered unless they have received a wider recognition outside that community.

In general geographic names in Greenland are a complex matter due to the diversity in exploration in the past. More details can be found in

http://www.geus.dk/UK/publications/geol-survey-dk-gl-bull/21/Pages/default.aspx
http://www.the-cryosphere.net/9/2215/2015/tc-9-2215-2015.pdf

Official names are administered by

http://www.oqaasileriffik.gl/en/oqaasileriffik/placenamescommittee

Die Vermessungsbehörden schreiben ja gerne so manches auf ihre Karten was oft mehr Wunschdenken ist, noch liegt die Schutzfrist für Datenbankschutz ("Extraktion von Daten") jedoch bei 15 Jahren und für anonyme persönliche geistige Schöpfungen (was für einen Gewässernamen dann doch etwas fragwürdig ist) bei 70 Jahren ab Veröffentlichung. Also schaut man hier:

http://greif.uni-greifswald.de/geogreif/geogreif-content/upload/bay/739Glonn1931Kopie.jpg

Hallo Liliental-Förster und willkommen bei OSM,

bei dieser Änderung scheint was schief gegangen zu sein, insbesondere der Node

osm.org/node/2616759120

scheint verrutscht und falsch verbunden zu sein.

Hello lenux,

i hope you are aware that this is now the only lake on earth with a coastline tag. The only effect this has is making life more difficult for those processing the coastline.

So please remove the coastline tag and keep it that way.

This does not seem like a good idea, lakes like these:

osm.org/way/21028225

osm.org/way/21028045

are quite clearly lakes and no maritime bays and the new coastline closure is way above the range of tidal or ocean current influence.

The Mackenzie River delta is strongly fluvially dominated - even if its shape due to the arctic setting does not look that much like it. If you want to read up on the area you can find quite extensive discussion in:

ftp://ftp.ems.psu.edu/data/pub/.snapshot/weekly.2/geosc/pub/dedmonds/Hill2001.pdf

Well - i don't know the local situation. But water outflow is quite high (it drains more than 200k square km in a fairly wet region) and the connections to the ocean are narrow so it seems a reasonable assumption - naming as 'lake' also indicates surveyors had the same impression.

Not really - wikipedia lists elevation at 2m which indicates no bidirectional water exchange so clearly a lake.

The baseline is usually the low water mark so it often differs significantly from the coastline in OSM. The old coastline was quite definitely too far landwards but it seems likely the current one is somewhat too low. But if you have local knowledge of actual water levels supporting your mapping that is fine. As said the situation is special so there is not really a good frame of reference.

You already removed the wetland=tidalflat so mapping looks consistent now and definitely closer to reality than before.

Hello chnav,

if this is correct (i.e. a tidal wetland) the coastline here is wrong - the OSM convention is to place the coastline at the tidal maximum, that means at the landward side of tidal flats.

The Caspian Sea is somewhat special since there are tidal, seasonal and longer term water level variations. Without any real knowledge of the situation on the ground just based on imagery it seems to me that the new coastline placement you did is too low and should better be near the outer edge of the wetland and the wetland itself should be tagged as a seasonal wetland. See here from some recent images where the extent of water cover is visible:

http://earthexplorer.usgs.gov/metadata/4923/LC81650282016083LGN00/
http://earthexplorer.usgs.gov/metadata/4923/LC81650282015208LGN00/

Hello elijose,

i am not sure what you are trying to map here but these roads do not exist in reality, please remove them again, OSM is not for drawing imaginary features.