Digital Geography

Military Expenditure on a map

Screenshot from 2014-07-17 14:34:15

Statistical data for a geographer is fun! War is not! Regardless what you think of the military it never hurts to be informed, so… Lets play a bit with military expenditure statistics. I’m using data from SIPRI (Stockholm International Peace Research Institute), which covers military expenditure for regions and countries based on for instance GDP. The data is in Excel format (.xlsx) which is a problem for QGIS, so it has to be converted to a format that QGIS understands. First however some other issues must be addressed. In order to use the years as field names they must be…

odyssey.js: your easy story mapping engine

story map of Germany worldcup 2014Reading my tweets can be somehow interesting: It seems like ESRI invented and exclusively owns the phrase “story map”: #storymap Tweets What IS a story map? To me a story map is the same like a map: a way of information distribution. According to ESRI: “Story maps use geography as a means of organizing and presenting information. They tell the story of a place, event, issue, trend, or pattern in a geographic context. They combine interactive maps with other rich content—text, photos, video, and audio—within user experiences that are basic and intuitive” (citation). Let’s sum up the characteristics: tell  a…

Advanced access to free climate data for Germany of the Climate Data Center

DWD

Since July 1st 2014, the Deutscher Wetterdienst (DWD) eased restrictions for the usage of climate data and provides users with a big dataset of free climate data for Germany. You can obtain the data, using the FTP-Server of the Climate Data Center (CDC). The following data in the following resolutions and formats are ready to download for free: measured Paramater at the DWD-Stations for climate in hourly, daily, monthly and annual resolution and phenology in annual resolution as txt derived Paramater at the DWD-Stations for soils (pot. and actual evaporation, soil moisture, soil temperature, max. depth of frost penetration over…

regular spaced points… interpolation madness…

rasterized point shapefile in QGISThe geodata department of the city of Berlin offers a great portfolio of free geodata for everyone to use. One dataset is the result of some LIDAR measurements and is offered as a txt with x,y and d values. This is commonly known as xyz data but should not be mistaken as a simple whatever-delimited text file. This dataset is regular spaced and therefore can be threatened easily with QGIS. But let me first show you some interpolation results which can be produced as well. Interpolational madness If you want to create raster data from a point shapefile or a…

short announcement: Berlin geodata downloadable…

DSM hillshadeI don’t know what’s wrong with the governmental insitutions in Germany/Berlin: They have this law, that all the geodata are somehow under an open license but to me it’s always a little hard to find it. Once you’re on the website you need to visit the site of Geodateninfrastruktur (GDI)->Geodienste to find sources for WFS, WMS or downloadable data: Once you find it, lots of data is waiting for you! you can get historical maps for Berlin, DOM and DEMs (in 2 and 5m ground resolution), soil key figures, ground water tables and other stuff. In the end you can…

reproject and filetype change in python/pyqgis for QGIS plugin

featured_2In my current work on the qgis2leaf plugin I had the idea to place raster data on a leaflet map as an image overlay. With this in mind and looking at a webmap I needed to consider a good filesize, a strict projection of EPSG:4326 and a strict filetype as well. So decision was: projecting everythin to EPSG:4326 and changing file type to *.jpg. I know, how to do this in the Terminal and in QGIS. But what options do you have using python/ pyqgis only? Terminal For doing this work in the terminal/shell/command line the one and only choice…

How many people live in this area?

Census.gov - Google Chrome_2014-06-26_08-58-31

Not long ago I was tasked with finding out how many people live within an arbitrary polygon. In this particular case, the polygon represented the portion of the United States within a drive-time of 10 hours. For this example, the polygon(s) can be anything you wish. This post will act as a tutorial of sorts on how to answer questions like these using python. Sorry to my Deutsch Freunden on this site, but this will be a U.S based answer as using the Census API is a key part of it. This is a classic case of the modifiable area unit problem.…

Create your own StoryMap

screenshot-from-2014-05-29-160341

Have you seen “the story maps” created on the ESRI website (http://storymaps.arcgis.com) or for that matter from http://storymap.knightlab.com/ or http://mapstory.org/. They are all frameworks for you to create “a story” with geographic connections, and they achieve this more or less successfully. Common for all of the above are that they are services, depending on the on-line framework. This makes it possible to present a more user friendly experience when you create the story, but at the same time you loose some flexibility and you need to be on-line. Here I’ll show how you can build a storymap yourself based on…

short announcement: new MOOC from our ESRI friends at Redlands

Learn What Spatial Analysis Can Do for You - Google Chrome_2014-06-23_12-54-29Today I came across this little page via a linkedin group (Link): This Massive Open Online Course (MOOC) is for people who know something about data analysis and want to learn about the special capabilities of spatial data analysis. Unfortunately not much is know regarding this course: Hands-on exercises, short video lectures, quizzes, case studies and discussion 6 weeks, 2-3 hours of study per week Certificate of completion and prizes But one thing is known: You’ll get free access to the full analytical capabilities of ArcGIS Online, Esri’s cloud-based GIS platform. See more and register here. Could someone comment whether…

Top 5 QGIS Plugins

GeoSearch - Routes

I have been using QGIS 2.2 for most of my GIS work for about 3 months now, so I have noticed that I keep on using some plugins over and over and I really wouldn’t be able live without them. So here is a list of my favorite top 5 QGIS plugins! Top 5 QGIS Plugins 1. OpenLayers plugin It was love at first use for the OpenLayers plugin.  It allows the user to load basemap from a different provides like Google, Bing, Yahoo, OSM (OpenStreetMap), Apple (I have NO idea what someone would want it) and Stamen. Now I…

How to build your own QGIS plugin

first test with values in the plugin and the python console

Since I’ve created the QGIS plugin qgis2leaf I was surprised how easy it is to create a plugin for QGIS. In this post I would like to show you how to build a basic buffer-plugin and give some tips for debugging and developing. the plugin template QGIS plugins are competely build in Python: the UI can be designed with QT designer using PyQT. The whole logic of the plugin needs to be written in Python as well. But lets be honest: It would be great if you would have  a starting point. In QGIS there is a plugin for this called…

ArcGIS server vs. Open Source GIS solutions

download speed and file sizes of given data sets in ESRI and open source GISoriginally posted from our friends @mappinggis Which program is better suited to serve geographic data on the web? ArcGIS Server form ESRI or open source ? This question is common in mailing lists and GIS-forums. The most consistent answer is that depends on the project. But in this post we will see some numbers to determine which is the best software to develop an application for web mapping: ArcGIS for Server ArcGIS for Server  was launched to replace ArcIMS, and its quality and functionality is unquestionable. In a way it is based on the flagship product of ESRI ArcGIS for desktop. But it has some disadvantages as well:   One ArcEditor license…

Soil Atlas and Soil Data

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If you are working on European soils, I’m sure you already know the website of the European Union Joint Research Center, the so called ‘European Soil Portal‘. If not, it’s your chance now to get in contact with many different soil data, maps and topics about soils – not only european soils.  Free soil and biodiversity atlas: At the beginning I would like to draw your attention to the great and powerful soil atlas you can download for several regions around the globe for free (PDF format). Follow the links to download the soil atlas (be aware that they contain large…