Category: Blog

OpenEcoMaps, eco-living maps using OpenStreetMap data, is now working again. Hooray! I decided to sit down and work out why the OpenLayers interface wasn’t working and it turned out to be quite simple to fix. You can now browse around maps of low carbon energy generators in London, veggie restaurants in Edinburgh, allotments in Exeter, recycling facilities in Glasgow and more! The data is updated every hour, direct from OpenStreetMap, and is available on maps and downloadable/reusable KML and GeoJSON files. The code is also in Github, so you could set-up your own version for another country if you like. There are still some of the layers that aren’t working because the underlying data isn’t being extracted from OpenStreetMap properly. But I’m very glad that, after well over six months with it completely broken, the web site basically works again!

Read More OpenEcoMaps is back!

For almost a year now, my pet project OpenEcoMaps has been broken. The vagaries of unreliable XAPI servers meant the system couldn’t download OpenStreetMap data to create all the KML files, and (I think) some changes to OpenLayers meant the web maps also stopped working. It has taken me a long time to work up the energy to fix these. Today I can happily say one half of the system is now working again, and the underlying code is much improved. OpenEcoMaps KML files, and now GeoJSON files, are being created again. Hooray! I switched from XAPI to the Overpass API; grabbed JSON which enabled me to write a more powerful function to turn this into usable objects (for example building a complete Python object for an allotment merging data from relevant nodes, ways and relations); wrote a new library to create GeoJSON files; refactored everything else to fit with…

Read More OpenEcoMaps halfway back

Ben Goldacre’s interesting programme on evidence-based policy making went out yesterday evening. Like so much of his work, I found myself alternately agreeing vigorously and disagreeing in exasperation. The trouble is not what he does say, but what he doesn’t. His central argument is a familiar one. In medicine, scientists determine what works using randomised controlled trials. Give one set of patients a pill, give another set a placebo, and see what difference the pill makes. Do this lots of times, trying to control for confounding variables (like the participants’ lifestyles) and if possible make it “double blind” by ensuring neither the participants nor the researchers conducting the test know which group anyone is in. This method gives us a high degree of certainty that some pills work while others don’t, or do so less well. It is far superior to simply acting on a hunch, monitoring a particular outcome…

Read More Ben Goldacre’s Bad Evidence

Darren Johnson has issued a report arguing that building new homes can’t solve London’s housing crisis alone. He suggests the Mayor should consider other solutions including smart regulations for the private rented sector, taxing land values and setting up land auctions. But there are two policies you won’t see in his list. Two policies that Greens often bring up in discussions about housing. I wanted to take some time this evening to explain why I think we should talk about them a little less, and in a very different light. Before I launch in, I would heartily recommend this blog entry by Liz Emerson as an overview of the sources of our housing crisis, to give an idea of why we need to act. The Green Party’s policy platform is chock-full of good ideas to rectify this, but when it comes to building new homes I think Greens sometimes find themselves on…

Read More Two false hopes that won’t solve London’s housing crisis

The OpenStreetMap GB project aims to measure and improve the quality of OSM data in Great Britain, cleaning it up to get rid of silly little data errors, and to make this cleaned up version available in formats that local and central government types are used to. I have been exploring whether I could use the Web Features Service as an easier source for landuse data (see my previous blogs on making a map of London’s green spaces and analysing Southwark’s landuse, which both required a somewhat complicated process to get the data set). In the process I’ve found it’s actually a great way to identify gaps and problems in our data. Browse around the map on the OpenStreetMap homepage and you might think we have an impressive coverage of residential landuse, playing fields and parks. But probe around with the WFS and you can spot all sorts of missing…

Read More Fixing problems with OSM-GB’s web service

Green Party MEPs have led campaigns in a number of areas I care about, including climate change, digital rights and employment rights. Jeam Lambert has led the charge on behalf of London since 1999, but I feel it is time to give a new person a crack of the whip. I believe that person should be Caroline Allen. I am writing this in a purely personal capacity, unconnected to my elected roles in my local party and the London Fed. When looking through the candidates’ materials, I was looking for a few qualities: 1. Strong understanding of complex policy to ensure they really can engage with and influence technical debates at the European level – Caroline has impressed me with her policy work for the national party, particularly in navigating through choppy waters around the science of GM and animal welfare to ensure we have a credible line, meaning we…

Read More Why I’m voting for Caroline Allen

Following my map of London’s green and blue infrastructure, I have been working on some analysis of the land uses. I was inspired and encouraged to try this by Liliana’s interesting work called “imagining all of Southwark“. Lili and Ari have managed to get the council to release lots of data on properties and car parking, and they are producing analysis of this data by postal code area and by street. They haven’t managed to get anything on land uses, so I thought, why not produce this with OpenStreetMap data? A few evenings later, here is the result shared on Google docs (direct link) covering the eight postal code areas that between them cover most of the borough (SE1, SE5, SE15, SE16, SE17, SE21, SE22, SE24): What the data means The “summary” worksheet shows the total land area, expressed in hectares (10,000 m2), for various different types of land coverage.…

Read More Analysing Southwark’s natural geography

I’ve been playing around with open data from OpenStreetMap and Natural England to make a pretty map of “green and blue infrastructure” in London. Here’s the result: You can download a PDF version suitable for printing here: natural_london. I’m pretty happy with the result, my first real attempt to produce something useful with QGIS. The data I used was: OpenStreetMap shapefiles for most features from Geofabrik, supplemented by… Manually retrieved commons and marshes using the Overpass API (not yet present in Geofabrik shapefiles) Natural England shapefiles for orchards, deciduous woodlands and sites of special scientific interest Ordnance Survey Boundary-Line shapefiles for the Greater London and London borough boundaries There’s no reason the Natural England data couldn’t be manually added to OpenStreetMap, giving us a complete dataset of natural features. I just chose to get on and do it this way rather than wait, or try to add all the data across areas…

Read More London’s natural geography

One of the odd things about contributing to OpenStreetMap is that you have no idea who is using the maps and the data. You spend hours, weeks, months, years even building up a wonderfully comprehensive database of geographic features in the area, all because it’s fun, because you believe in the project’s ideals or you need the data for your own project. But does anyone else use it? It would be depressing if the answer was “no”. So I get cheered every time I see documents like this: That’s an excerpt from a presentation by Southwark Living Streets. They took the Mayor of London’s transport advisor around Elephant & Castle to show how unfriendly and dangerous the area is for pedestrians, and illustrated the whole thing with OpenStreetMap. The chap who made this loves OSM, he told me he realised how useful it could be when he noticed we had…

Read More Mapping for pedestrians

“It’s the economy, stupid” has become something of a mantra among many in the Green Party in recent years. Wary of repeating the crash in votes the party experience in the early 1990s recession, we have sought to persuade the public that we have something credible to say on the pressing economic issues of the day. Caroline Allen has said: I do not believe we will succeed solely by telling people what we are against, we must articulate a positive alternative. I believe we have a good framework but need to do more work here. But beyond commentary and our “one million green jobs” proposal, I’m not what our positive economic programme for the nation is. Let me explain. Green commentary Greens have some compelling things to say about our present economic troubles. For example, we have suggested that technological innovation may not be able to keep up with rising resource…

Read More What is our Green economic programme?