GIS

Here’s some samples from my final work for Introduction to advanced geoinformatics. Writing and academic reading took many hours so i’m finally happy to finish this course. My report was about defining visitor hotspots in Nuuksio national park with Flickr and Instagram data.

 

“In 2010’s smart phone development has made social media crucial part of everyday life and it has shaped urban life through production of geotagged text, photo and image data (Shelton, Poorthuis & Zook, 2015). Tags used in social media posts are important feature in describing important aspects of photos (Dunkel, 2015). Social media behavior and photo sharing in different platforms such as Instagram and Flickr have made social media very interesting source of data as handheld technology enables collection of geospatial data in great velocity minimizes delay between data collection and dissemination (Smith, Goodchild & Longley, 2007). Social media data has been labeled as “Big data” as it is continuously generated and it’s rich in content (Tenkanen et al., 2017). Uploaded and geotagged photo data enables to investigate for example visitors in national parks which otherwise would be difficult.”

” Main data used in analysis work are Flickr and Instagram photo data. For their properties, see table 1. Background map for the visualization was created from orthophotos, hillshade and road data. Road data was extracted from national Digiroad service and from HSY land use data. For their properties, see table 2.”

” After trimming the image data, I focused more on the other datasets I might find useful in analysis. I downloaded eleven orthophotos from National Land Survey of Finland online File service of open data (https://tiedostopalvelu.maanmittauslaitos.fi/tp/kartta). Then I imported TIFF photos to QGIS canvas and deleted the OpenStreetMap. National Land Survey of Finland also provides accurate Digital Elevation Model (DEM) in File service so I downloaded DEM’s for orthophotos which I previously imported. Once DEM’s were imported to QGIS I visualized them as hillshade and exaggerated topography by Z-value of four. With exaggerated topography differences stand out much better and gives nice visualization with orthophotos.”

“Several hotspots can be seen from trimmed image data. Comparison with official map from Nuuksio reveals that most of the hotspots are campfire places that are easily accessible by official routes. Also Nuuksio Nature Center Haltia is one hotspot. Assumption that I made Most popular destination according to data are Nature Center Haltia and campfire places of Kattila, Mustalampi and Mustalampi Pöksynhaara (Picture 4, compare official map from Nuuksio in picture 6). Flickr data mentioning “Nuuksio” concentrates more accurately in actual Nuuksio area than Instagram data. Amount of Instagram pictures is surprisingly low in Nuuksio because there is concentration of Nuuksio related images in central Helsinki which makes Flickr data more reliable. Flickr data is also more scattered around the National Park and seems to be more better located.”

“Accuracy of geotagged photos also vary a lot depending on social media platform. Different locations may be aggregated to single point by platform or users might upload pictures of several points from one physical location which can affect geotagging accuracy (Hochmair et al., 2018). Instagram and Flickr use mobile devices or cameras GPS to geotag photos but in Flickr it is also possible to manually click the photos to right locations on webmap when user uploads the photos (Fisher et al., 2018). With this data, Flickr users seem to be more familiar with nature as they travel further away from official routes.”

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