[Proj] Standard projection for Mediterranean basin

[Noel Zinn]

As a rule of thumb choose your standard parallels one sixth of the distance
inside the North and South boundaries of your area of interest.  -Noel

 

  _____  

From: proj-bounces at lists.maptools.org
[mailto:proj-bounces at lists.maptools.org] On Behalf Of Luigi Ponti
Sent: Sunday, February 14, 2010 12:44 PM
To: geraldi.evenden at gmail.com; PROJ.4 and general Projections Discussions
Subject: Re: [Proj] Standard projection for Mediterranean basin

 

On 20:59, Gerald I. Evenden wrote: 

On Saturday 13 February 2010 12:28:57 pm Luigi Ponti wrote:
  

Hello,
 
I use PROJ.4 via GRASS GIS, and I would like to know if anyone is aware
of a standard projection for mapping the whole Mediterranean basin. I
need to do raster-based statistics on the maps, so I guess what I am
looking for is an equal area projection.
 
What I have found on the Web is a GIS built by the Joint Research Center
(JRC http://www.jrc.ec.europa.eu/) that used Lambert Azimuthal Equal
Area (LAEA) for the Mediterranean:
http://re.jrc.ec.europa.eu/pvgis/info/faq.htm#projection
 
However, it adopted the same projection center for both Europe and the
Mediterranean (0 °E and 48 °N). Is this correct?
 
There is also a workshop report
http://www.ec-gis.org/sdi/publist/pdfs/annoni-etal2003eur.pdf
 
that recommended LAEA with projection center 9 °E and 53 °N to be used
for statistical mapping in the European Union.
 
Based on this background it seems like LAEA would be fine. However, I am
unsure if there is a standard projection center and datum.
 
Thank you for any hints. Kind regards,
 
Luigi
 
_______________________________________________
Proj mailing list
Proj at lists.maptools.org
http://lists.maptools.org/mailman/listinfo/proj
    

 
Personal opinion: because you seem to have your own project needs that has
not 
shown a need to match any existing projection I would, because of the
general 
E-W shape of your region, select Albers Equal Area conic. With reasonably 
selected parallels is should give you less distortion at the extremities
than 
the azimuthal projection.
  


Thank you -- this sounds like a very good suggestion.




 
A little parameter tuning needs to be done.
  


Really have no clue on how to go about this, but will give it a try. From
what you say, I understand that it would basically be a matter of finding
the right standard parallels: is there a rule of thumb for this?

Thanks again,

Luigi




 
I would not be prejudiced by projections where the needs to cover the entire

continent are are the primary consideration.
 
  

 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.maptools.org/pipermail/proj/attachments/20100214/34759904/attachment.htm