I was able to talk to some people from NAMRIA and they said that the
"7,641" number is actually Secretary Paje jumping the gun. This number is
not validated and is just an initial comparison of the IFSAR data with
existing data. There may be data anomalies (because IFSAR is not foolproof)
so I was told that 7,641 should be taken as just an estimate and *not* as
official data.
I also asked if there is a definitive database of islands. I was told that
there is still no official/accurate database of islands of the Philippines,
but that there is an ongoing effort to validate the data that they do have.
I was also told that the ~7,100 number is based on NAMRIA's 1:250,000 maps
which were originally based on the US-era maps. So that means that small
islands were not counted, and there would be inaccuracies such as with
names, land area, and even location.
On Sat, Feb 20, 2016 at 5:17 PM, Eugene Alvin Villar
wrote:
> The Census Atlas provided one criterion for the definition of an island:
> it has to be above water at high tide.
>
> On Sat, Feb 20, 2016 at 10:02 AM, Jim Morgan wrote:
>
>> On Saturday, 20 February, 2016 09:32 AM, Eugene Alvin Villar wrote:
>>
>>> According to the latest news, there are now "exactly" 7,641 islands.
>>> This is stated by the so-called Philippine Islands Measurements Project of
>>> NAMRIA.
>>> I have previously e-mailed NAMRIA to get info on how they keep track of
>>> islands and how the most often quoted figure of 7,107 islands was derived.
>>> Predictably I didn't get any definitive answer.
>>>
>> I remember hearing that the number of islands varies depending on whether
>> its high tide or low tide, so any figure which claims to be exact should be
>> treated with suspicion. Unless they've come up with a definition of island
>> which copes with this -- maybe it has to be visible for 12 hours in a 24
>> hour period! :-) Also when does a rock become an island?
>>
>> Then there's the matter of islands whose ownership is in dispute, and the
>> ones which are being blatantly stolen by our neighbours. But lets not get
>> into that here ... :-)
>>
>> Jim
>>
>>
>>
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