BayGeo's R for GIS (Fall 2025)

Overview

This is a five-session (10-hour) Zoom workshop covering mapping and analysis with R. We’ll focus on the sf and terra packages, weave in good data-wrangling habits with the tidyverse, and finish by designing beautiful maps. Each class meeting mixes concise demos with guided, hands-on exercises using Bay Area open data plus “sandbox” time so you can experiment with your own projects while the instructor is on hand to help.

By the end of this workshop you’ll be able to import, clean, analyze, and visualize both vector and raster data entirely in R. Some prior experience with R is expected, but we will go over the basics again on the first day.

An external monitor is highly recommended so you can view the instructor's screen share on one monitor, and work on RStudio on the other. Throughout the workshop, we will see how to use ChatGPT to obtain starter code and troubleshoot error messages. All participants are strongly encouraged to sign-up for a free ChatGPT account if you don't already have one (start at https://chat.openai.com).

Workshop Dates:

All classes are from 3:00 p.m. - 5:00 p.m. PT on Zoom

• Thursday October 9
• Thursday October 16
• Thursday October 23
• Thursday October 30
• Thursday November 6

Learning Objectives

• By the end of the workshop, you will be able to:
• Set up a reproducible R project for geospatial work.
• Write R scripts to import tabular, vector, and raster data.
• Create clear static maps with tmap and ggplot.
• Do basic geospatial manipulations including projections and format conversions.
• Query spatial objects using attribute values and spatial relationships.
• Perform common geoprocessing tasks including joins, buffering, and clipping.
• Troubleshoot typical R GIS pitfalls and know where to find community resources for continued 

Class Outline

Class 1: Spatial Data Classes and Importing Vector Data

• RStudio tour, projects, packages
• Spatial data classes (vector vs raster)
• Importing and exporting vector data
• Basic plotting 

Class 2: Vector Data Manipulations

• Common manipulations in sf 
• Geometry operations: buffer, intersect, dissolve
• Converting data formats
• Visualization with tmap

Class 3: Attribute Queries and Automation

• Working with attribute tables
• Attribute and spatial joins
• Automation and batch processing

Class 4: Raster Data and Geoprocessing

• Raster ingestion and metadata
• Zonal statistics
• Geoprocessing functions for vectors and rasters
• Mapping with raster and vector data

Class 5: Making Maps in R

• Static mapping: ggplot2 and tmap
• Interactive web maps: leaflet, mapview
• Color palettes, legends, scale bars, exporting

Meet your Instructor: Sara Winsemius

Sara Winsemius is an ORISE postdoctoral researcher with the US Forest Service Rocky Mountain Research Station and the Biodiversity Research and Policy Center. She does geospatial research using remote sensing to study ecosystem changes across the US. She recently earned her PhD at UC Davis in Ecology, where she focused on remote sensing applications for forest biomass and fire severity, and taught remote sensing, intro to GIS, urban plant identification, intro to plant sciences, and arborism/urban tree maintenance labs.

She also holds a BS in Environmental Science from UC Berkeley and has worked in agroecology and native dune restoration.

Sara lives in Davis and can be found biking and walking around the flatlands, or hiking around in the Sierra Nevada and coast ranges when she gets the chance.