Inverse Distance Weighting and Kriging in R

I posted a few months ago about a new R package I wrote with Filipe Matias-- it's available for download on GitHub. Last week we extended the GitHub tutorial to include interpolation methods and raster visualization/mapping example code. Spatially Challenged readers have asked me to write tutorials on these techniques before, but I had been… Continue reading Inverse Distance Weighting and Kriging in R

EJSCREEN: a tool for visualizing Environmental Justice

This week I learned about a great tool from the US EPA called EJSCREEN, which allows users to visualize and download data related to environmental justice. The US has a long history of environmental racism, including building highways through predominantly black neighborhoods and using former factory sites for low-income housing. Pollution and increased noise exposure… Continue reading EJSCREEN: a tool for visualizing Environmental Justice

Paper Size in QGIS 3 Print Layouts

I make most of my maps for publications and presentations in QGIS using the Print Layout feature. This is a wonderfully detailed tutorial if you want to learn more about print layouts. Right now I'm using the print layout to make maps of pH, organic matter, and soil test potassium to include in an update… Continue reading Paper Size in QGIS 3 Print Layouts

Global Yield Gap Atlas

I've used the Global Yield Gap Atlas for a few projects over the last couple years, and it's a great resource. GYGA measures the yield gap (difference between potential yield and achieved yield) of many crops grown in many environments, and provides downloadable data for other researchers. One tool I use from GYGA is their… Continue reading Global Yield Gap Atlas

US Satellite Images and #NoPlant19

Those of you complaining about the weather may feel validated by this headline from CNN (article here). For the over 1 in 10 Americans work in agriculture and related industries (source), this has real consequences. The increased rain this spring delayed planting, and in some places planting was prevented altogether. The Washington Post has some… Continue reading US Satellite Images and #NoPlant19

Getting Category Colors into QGIS from ColorBrewer

Are you as obsessed with ColorBrewer as I am? I am making a map where I color Ohio counties based on region, and used ColorBrewer to pick colors. The first thing I did was go to ColorBrewer and find a qualitative color set for 5 categories of data. Next I used the HEX codes provided… Continue reading Getting Category Colors into QGIS from ColorBrewer

EPSG Numbers and Coordinate Reference Systems

Over the last month or so I've had a little series about how we describe positions on the globe and how we visualize spherical space on a 2D map. I started with big picture information, like why we care about map projections. Last week began giving more concrete advice for picking a projected or unprojected… Continue reading EPSG Numbers and Coordinate Reference Systems