Zac Snyder
Geospatial Science · Environmental Research · Energy

Zac
Snyder

GIS Analyst Spatial Analysis & Modeling Remote Sensing Data Analysis

I focus on spatial analysis, environmental data, and mapping. Most of my work is terrain and hydrology modeling, site suitability, and getting messy datasets into shape. I've used GIS both in school and professionally in the energy sector, and I like using spatial data to answer practical questions with maps people can actually use.

M.S. GIS: Cartography & Remote SensingLiberty University, 2026
GIS contractorGradient Geothermal, 2025 to present
GIS internGradient Geothermal, summer 2025
B.A. BiologyMSU Denver, 2023
Selected work

Selected projects

These projects come from my master's program and my own independent work. My professional work is confidential, but I'm happy to walk through it in an interview. Click any map to see it full size.

Three final sites · kriged rainfall 42 to 71 in
Site suitability · capstone

Trash-Be-Gone: Landfill Site Selection in Florida

Type
M.S. capstone, 2026
Tools
Select by Attributes, Buffer, Erase, Intersect, Slope, Reclassify, Kriging
Data
Statewide parcels, roads, population, elevation, rainfall

For my capstone, I had to find a spot for a new landfill in Florida. A site had to be big enough, close to roads, far enough from people, fairly flat, and not too rainy.

I turned each of those rules into a spatial filter and narrowed the state's parcels down one step at a time, then used kriging to estimate rainfall everywhere. Three sites made it through: Okeechobee, Lake Placid, and Yulee.

About 330 acres converted · 92% accuracy
Swiping from 2018 to 2026 in ArcGIS Pro
Remote sensing · change detection

New Development West of Downtown Suffolk, 2018 to 2026

Type
Independent project, 2026
Tools
ArcGIS Pro, Raster Calculator, NDVI differencing, accuracy assessment
Data
Sentinel-2 L2A (Copernicus), Esri World Imagery Wayback

A big warehouse district has been going up west of downtown Suffolk, Virginia, and I wanted to measure how much forest and farmland it replaced.

I downloaded Sentinel-2 red and near-infrared bands for August 2018 and July 2026, calculated NDVI for each year, and subtracted them. About 330 acres went from dense vegetation to roofs, pavement, or cleared ground.

To check it, I placed 60 stratified random points and labeled each one by hand against high-resolution imagery from both years. The map came out 92% accurate (kappa 0.83). It's a little conservative: most of its misses were real development it didn't flag, so the acreage is probably a slight undercount.

Trees 63% · grass 25% · bare ground 11%
Remote sensing · image classification

Tree Cover in Nebraska's Loess Canyons

Type
M.S. coursework, 2025
Tools
ArcGIS Pro, training samples, Maximum Likelihood Classification
Data
USDA NAIP aerial imagery, 2014 to 2018

The Loess Canyons are steep canyon country in southwest Nebraska, where eastern redcedar has been spreading into grassland. The goal was to map how much of one area is covered by trees.

I drew training samples for trees, grass, and bare ground on NAIP aerial imagery, then ran a maximum likelihood classification to sort every pixel into one of the three. I put the imagery and the result side by side so you can check the classification against what's really on the ground.

Trees came out at 63% of the study area, with grass at 25% and bare ground at 11%. Most of the grass sits along the canyon floors, and the bare ground shows up as bright patches on the slopes.

52 weeks of eBird relative abundance, animated in ArcGIS Pro
Data visualization · animation

Ruby-throated Hummingbird: One Year of Migration

Type
Independent project, 2026
Tools
ArcGIS Pro, time-enabled rasters, animation, Python
Data
eBird Status & Trends weekly relative abundance, Cornell Lab of Ornithology

Ruby-throated Hummingbirds spend the winter in Mexico and Central America, then many of them fly straight across the Gulf of Mexico each spring. I wanted to show that whole year in one short clip.

The data is eBird's modeled weekly relative abundance, not my own analysis. My part was getting it to work and making it readable. The 52 weekly rasters came without a usable projection, so they landed in the wrong place on the map. After some troubleshooting, they turned out to be in the Equal Earth projection. Once that was defined and they were reprojected, I built them into a time-enabled raster dataset in ArcGIS Pro.

From there I designed the symbology, framed the map on the full migration range, and animated it week by week in ArcGIS Pro. The titles, date counter, and final timing were added with a Python script.

Elevation 196 to 376 m · Root River tributary
Watershed delineation

Brush Valley Creek Watershed, Houston County, Minnesota

Type
M.S. coursework, 2026
Tools
ArcGIS Pro, Spatial Analyst Hydrology
Data
DEM, topographic basemap

I wanted to find out exactly which land drains into Brush Valley Creek, a small stream that feeds the Root River in southeast Minnesota.

Starting from an elevation model, I filled the sinks, figured out which way water flows across every cell, pulled out the streams, and traced everything upstream of the outlet. Then I laid it over a faded topo map so you can see the roads and the town of Hokah nearby.

Eight steps, DEM to sub-watersheds
Hydrologic analysis

Pumpkin Creek Watershed, Oklahoma

Type
M.S. coursework, 2026
Tools
ArcGIS Pro, Stream to Feature, Watershed
Output
Strahler order 1 to 4

This one walks through the whole hydrology process, one step per panel.

It starts with raw elevation and builds up through slope, aspect, flow direction, and flow accumulation until you get the stream network, ranked by size, and the smaller watersheds that feed it. I put all eight panels on one page so you can follow how each step leads to the next.

Four panels at one shared scale, 1:239,966
Cost surface analysis

Road Construction Cost Analysis, Duluth, Minnesota

Type
M.S. coursework, 2026
Tools
Euclidean Distance, Slope, Raster Calculator
Range
$0 to $25,000 per cell

The question was simple: if you needed to build new roads around Duluth, where would it cost the least?

I mapped where you can actually build, how far each spot is from an existing road, and how steep the ground is, then combined them into one cost map. The cheap areas sit close to the roads you already have, and the steep bluffs along Lake Superior get expensive fast.

Elevation 721 to 4,307 m
Terrain cartography

Mount Shasta, Northern California: Elevation and Relief

Type
M.S. coursework, 2026
Tools
Hillshade, layered symbology
Focus
Map design and legibility

This one is mostly about design. I wanted Mount Shasta to look like a mountain the moment you see it, without needing the legend.

I made a hillshade from the elevation data, laid a color ramp over it, and kept the title and legend small so the terrain stays the focus.

Current research

Predicting coral bleaching risk across the Florida Keys

I'm working on a paper about this right now.

Right now, you usually only know a reef bleached after divers go out and survey it. I'm building a model that tries to predict which reef sites are most likely to bleach before that happens, using things like ocean heat stress, depth, and light. It's trained on almost 20 years of survey data.

Study area
Florida Keys reef tract
Records
4,537 site-year survey observations, 2005 to 2023
Predictors
Thermal stress, long-term temperature history, depth, light, and reef habitat
Model
Balanced random forest, tested on held-out recent years
Outputs
Predicted bleaching probability mapped at each survey site in ArcGIS Pro
InputsReef survey recordsplus heat stress, depth, light, and habitat layers
ModelBalanced random foresttrained on earlier years, tested on recent ones
OutputBleaching risk mappredicted probability at each survey site

I'll post the maps and results here once the paper is out.

Capabilities

What I can help with

GIS software

ArcGIS Pro, Spatial Analyst, QGIS, ArcGIS Online (basic)

Spatial analysis

Spatial joins, buffers, overlays, raster analysis, cost surfaces, site suitability

Terrain and hydrology

DEM processing, watershed delineation, flow direction and accumulation, stream ordering, slope, aspect, hillshade

Remote sensing

Landsat and other satellite imagery

Spatial modeling

Random forest, kriging, IDW and spline interpolation, predictive modeling

Automation

Python and ArcPy (working knowledge), mainly for automating repetitive GIS tasks

Data management

Cleaning and validating messy source data, QA/QC, attribute queries, building map-ready datasets

Cartography

Thematic maps, terrain visualization, multi-panel layouts, plain-language legends

Certifications

Remote Sensing and Mapping for Coral Reef Conservation, The Nature Conservancy (2026) · Esri Python Scripting for ArcGIS

Communication

I've taught middle school science and led college study sessions, so I'm used to explaining technical work to people outside the field.

About

A bit about me

I grew up in Colorado and have loved wildlife for as long as I can remember. That's what got me into biology. After college I worked in an environmental testing lab, then started teaching, and along the way I found GIS. It ended up pulling together everything I already liked.

These days I do contract GIS work for Gradient Geothermal and keep building projects like the ones above. Long term, I'd love to use these skills on environmental and conservation work.

  1. GIS contractor, Gradient GeothermalSite suitability analysis and GIS data work for energy projects.
  2. GIS intern, Gradient GeothermalI compiled and cleaned large well datasets, ranked states and counties by how promising they looked, and made maps the team used to decide where to focus.
  3. M.S. in GIS: Cartography & Remote Sensing, Liberty University
  4. Middle school science teacher, Virginia Beach
  5. Water Analyst I, environmental testing lab
  6. Research assistant, MSU DenverCoral reef ecology research, including chlorophyll-a fluorescence imaging and coral nursery work, with 20+ scientific dives in the Florida Keys.
  7. B.A. Biology, MSU Denver
Contact

Let's talk

Available for part-time GIS contract work

I'm open to GIS analyst roles and contract projects, big or small. Email is the easiest way to reach me.

LinkedIn: linkedin.com/in/zachary-snyder-3167b7276

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