0
Upcoming SlideShare
×

Thanks for flagging this SlideShare!

Oops! An error has occurred.

×
Saving this for later? Get the SlideShare app to save on your phone or tablet. Read anywhere, anytime – even offline.
Standard text messaging rates apply

# Apps4 finland shapefiles, wgs84 and other odd terms

2,760

Published on

Published in: Technology
0 Likes
Statistics
Notes
• Full Name
Comment goes here.

Are you sure you want to Yes No
• Be the first to comment

• Be the first to like this

Views
Total Views
2,760
On Slideshare
0
From Embeds
0
Number of Embeds
0
Actions
Shares
0
4
0
Likes
0
Embeds 0
No embeds

No notes for slide

### Transcript

• 1. Shapefiles, WGS84 and other odd terms Workshop on Open Location Data Pekka Sarkola
• 2. 21/09/2011 2 HistoryFinland first time on the map by Jacob Ziegler (1532)
• 3. 21/09/2011 3File formats
• 4. 21/09/2011 4 Combination Roughly 2000 – 3000 coordinate systems Around 300 commonly used GIS file formats
• 5. 21/09/2011 5 Coordinate systems Polar Coordinate systemCartesian coordinate system Geographic coordinate system
• 6. 21/09/2011 6 Coordinate systems – no problems... What is origin? What is direction? What is unit of measurement? You have choices:  Thousands of different coordinate systems  Good ones and bad ones  Old vs new  Local vs global
• 7. 21/09/2011 7 Geographic Coordinate Systems Latitude (leveys), longitude (pituus) and ellipsoid height Common datums / geodetic systems  WGS 84, 72, 64, and 60  ETRS89  NAD83 / NAD27 : USA  OSGB36: GB  ED50: European Datum  Hayford International 1924: base of
• 8. 21/09/2011 8Demo
• 9. 21/09/2011 9 Map projections: Basic challenge Your paper map and your computer screen is flat World is not!
• 10. 21/09/2011 10 Map projections Always distortion of  Area  Shape  Direction  Bearing  Distance  Scale
• 11. 21/09/2011 11Universal Transverse Mercator (UTM)
• 12. 21/09/2011 12 Finnish Coordinate Systems Kartastokoordinaattijärjestelmä (KKJ)  Old one, from 1970’s  Map projection:  Transverse mercator, 6 zones EUREF-FIN  New, based on ETRS89  Several map projections  ETRS-TM35FIN  ETRS-TM21, 27, 33  ETRS-GK19-31
• 13. 21/09/2011 13Web mercator
• 14. 21/09/2011 14
• 15. 21/09/2011 15 Georeferencing, geotagging, Georeferencing  ”To georeference something means to define its existence in physical space”, Wikipedia  Especially for aerial and satellite imagery Geotagging  Add coordinates to single item, like picture taken with mobile phone
• 16. 21/09/2011 16 Geocoding• Transform address / place name to coordinates D2.8.I.5 INSPIRE Data Specification on Addresses – Guidelines
• 17. 21/09/2011 17Questions?