On 2008-02-25 06:56:50 -0800, mankoff <mankoff@[EMAIL PROTECTED]
> said:
> On Feb 24, 2:54 pm, Paul Levine <paul.lev...@[EMAIL PROTECTED]
> wrote:
>> On 2008-02-22 09:48:38 -0800, mankoff <mank...@[EMAIL PROTECTED]
> said:
>>
>>
>>
>>>>> Polar Stereographic projection with 71=B0S as the latitude of true s
> cale
>>>>> and 0=B0E as the central meridian.
>>
>>> ;; this is the projection the data is distributed on
>>> stereo = map_proj_init('Polar Stereographic', /GCTP, DATUM=8, $
>>> CENTER_LONGITUDE=0, CEN
> TER_LATITUDE=-90)
>>
>> You must change the CENTER_LATITUDE to -71
>>
>> Polar stereographic projections are free of aereal distortion at only
>> one latitude, with aereal distortion increasing both north and south of
>> this latitude. In the case of your data, that latitude is 71 south.
>
>> FWIW, the northern-hemisphere sea ice data distributed by the NSIDC is
>> centered at 70 north.
>>
>> HTH,
>> Paul
>
> It does help. Image is better aligned. But still not accurate :(.
Is the inaccuracy greater or lesser than one pixel?
|
