[Talk-us] Ka'ula Rock Missing from Yahoo Satellite Imagery

Scott Atwood scott.roy.atwood at gmail.com
Tue Oct 6 01:15:49 BST 2009


I'm certain these islands and atolls exist, and that it is a problem with
the Yahoo imagery.  All of the publicly accessible satellite imagery seems
to be of variable resolution, depending on the perceived importance of the
area in question (or other factors), so it isn't too surprising that barren,
uninhabited specks of land in the middle of the Pacific Ocean aren't a high
priority for high resolution satellite imagery from Yahoo.

Other than Yahoo, is there any other source for high quality satellite or
aerial photography that can be used by the OSM project that covers the
Northwest Hawaiian Islands?

Many other islands and atolls in the northwestern portion of the archipelago
seem to be missing from the Yahoo imagery as well:
Kure Atoll:  missing
Midway Atoll:  present
Pearl and Hermes Atoll:  present
Lisianski:  missing
Laysan: present but very low resolution
Maro Reef:  missing (but only has about 1 acre of land, which may be tidally
submerged)
Gardner Pinnacles:  missing
French Frigate Shoals:  missing (or present at an absurdly low resolution)
Necker Island:  missing
Nihoa: missing

In addition, the PGS coastline data seems to be missing for Necker Island,
Gardner Pinnacles, and Maro Reef (if applicable given it's tidal nature).

Also Maro Reef doesn't seem to be included in the recently imported Honolulu
Country boundary data, possibly due to its tidal nature.

-Scott

On Mon, Oct 5, 2009 at 4:15 PM, Apollinaris Schoell <aschoell at gmail.com>wrote:

> have seen other small islets missing in yahoo, but they are seen in google
> imagesmust be a yahoo problem
>
>
> On Mon, Oct 5, 2009 at 2:31 PM, Scott Atwood <scott.roy.atwood at gmail.com>wrote:
>
>> Kaʻula Rock is a tiny islet a couple of dozen miles southeast of Niʻihau
>> in the Hawaiian Islands.  The islet appears in the imported PGS coastline
>> data and in the recently imported TIGER boundary data.  But even at maximum
>> zoom, the islet doesn't appear in the Yahoo satellite imagery.  I was hoping
>> to fine-tune the coastline data from the photos.
>> Does anyone know why this islet doesn't appear in the Yahoo imagery?  Are
>> the over-optimizing the data they serve by sending out generic sea tiles for
>> areas that they think have no land, and accidentally paving over this tiny
>> islet?
>>
>> -Scott
>>
>> --
>> Scott Atwood
>>
>> Cycle tracks will abound in Utopia.  ~H.G. Wells
>>
>>
>>
>> _______________________________________________
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>>
>>
>


-- 
Scott Atwood

Cycle tracks will abound in Utopia.  ~H.G. Wells
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