Chris Soulard has worked for the U.S. Geological Survey since 2002. He is currently a supervisory research geographer working with the Western Geographic Science Center in Moffett Field, CA.
I started my career with the U.S. Geological Survey in 2002 as a student intern and have never looked back, fully embracing my role as a civil servant. For over 20 years, I have had the fortune to work on a wide range of remote sensing into projects focusing on multi-temporal change analyses using Landsat imagery and aerial photography, most notably the Land Cover Trends Project. I have also had many opportunities to expand my research scope, including community vulnerability assessments of tsunami and volcanic lahar hazards in the Pacific Northwest, terrestrial laser scanning to monitor soil and vegetation changes in the Mojave Desert and elsewhere, land-use/land-cover forecasting for the Western United States, and vegetation change analyses using Google Earth Engine cloud computing. My career with the U.S. Geological Survey has afforded me the chance to develop technical geospatial and geostatistical research expertise, as well as soft skills like project management, leadership, and communication. I currently serve as the Principal Investigator of the PLACE Project (Patterns in the Landscape – Analyses of Cause and Effect) and supervise the Ecosystem Dynamics Team.
Professional Experience
2020 - present: Supervisory Research Geographer, United States Geological Survey (USGS)
2013 - 2020: Research Geographer, United States Geological Survey (USGS)
2002 - 2013: Geographer, United States Geological Survey (USGS)
Education and Certifications
B.A. in Geography, University of California Santa Barbara, 2003*
*Magna Cum Laude
B.A. in Environmental Studies, University of California Santa Barbara, 2003**
**Environmental Studies Honors Award
M.A. in Geographic Information Science with emphasis in remote sensing and land cover change, San Jose State University, 2005
Science and Products
Volcanoes
Identifying Historical Drivers of Vegetation Change to Inform Future Management of Federal Lands in the Northern Great Basin
Web Mapping Application for a Historical Geologic Field Photo Collection
Patterns in the Landscape – Analyses of Cause and Effect
Land Cover Trends
Integration of Land Cover Trends Field Photography with an Online Map Service
Assessing the Vulnerability of Dryland Ecosystems to Drought in the Western U.S.
Linking Extreme Storms to Changes in Precipitation, Ecosystems, and Wildfire Patterns in the Sierra Nevada
County-level maps of cropland surface water inundation measured from Landsat and MODIS
National Surface Water Maps using Daily MODIS Satellite Data for the Conterminous United States, 2003-2019
DSWEmod surface water map composites generated from daily MODIS images - California
Spatially-explicit land-cover scenarios of federal lands in the northern Great Basin, 2018-2050
Implementation of a Surface Water Extent Model using Cloud-Based Remote Sensing - Code and Maps
Phenology pattern data indicating recovery trajectories of ponderosa pine forests after high-severity fires
Datasets for analyzing stream gage discharge and Landsat imagery integration in the greater Central Valley, California from 1984 to 2015
Data - Forest harvest patterns on private lands in the Cascade Mountains, Washington, USA
Data on influence of atmospheric rivers on vegetation productivity and fire patterns in the southwestern US
Land Cover Trends Dataset, 2000-2011
Using Landsat and MODIS satellite collections to examine extent, timing, and potential impacts of surface water inundation in California croplands☆
Analysis of surface water trends for the conterminous United States using MODIS satellite data, 2003–2019
DSWEmod - The production of high-frequency surface water map composites from daily MODIS images
Solar and sensor geometry, not vegetation response, drive satellite NDVI phenology in widespread ecosystems of the western United States
Application of empirical land-cover changes to construct climate change scenarios in federally managed lands
Implementation of a surface water extent model in Cambodia using cloud-based remote sensing
Phenology patterns indicate recovery trajectories of ponderosa pine forests after high-severity fires
Landsat time series assessment of invasive annual grasses following energy development
Integrating stream gage data and Landsat imagery to complete time-series of surface water extents in Central Valley, California
Removing rural roads from the National Land Cover Database to create improved urban maps for the United States, 1992-2011
Forest harvest patterns on private lands in the Cascade Mountains, Washington, USA
Projecting community changes in hazard exposure to support long-term risk reduction: A case study of tsunami hazards in the U.S. Pacific Northwest
DSWE_GEE v1.0.0
Science and Products
- Science
Volcanoes
As the 1980 Mount St. Helens eruption showed, volcanoes pose significant threats to U.S. communities. Potential hazards posed by U.S. volcanoes include tephra falls, pyroclastic flows and surges, VOG, ballistic projectiles, lahar and lava flows. In collaboration with researchers from the USGS Volcano Hazards Program, the Hazards Vulnerability Team worked on better understanding and communicating...Identifying Historical Drivers of Vegetation Change to Inform Future Management of Federal Lands in the Northern Great Basin
The sagebrush rangelands of the Great Basin provide crucial habitat for a diversity of wildlife, including the pronghorn and the greater sage-grouse. These water-limited, highly-managed ecosystems have already been degraded by wildfires, the expansion of invasive grasses, and livestock grazing, and are expected to experience additional stress as climate and land use conditions change. Effective maWeb Mapping Application for a Historical Geologic Field Photo Collection
Geotagged photographs have become a useful medium for recording, analyzing, and communicating Earth science phenomena. Despite their utility, many field photographs are not published or preserved in a spatial or accessible format—oftentimes because of confusion about photograph metadata, a lack of stability, or user customization in free photo sharing platforms. After receiving a request to releas...Patterns in the Landscape – Analyses of Cause and Effect
Understanding the rates and causes of land-use/land-cover (LULC) change helps answer questions about what, where, how, and why the Earth’s surface is changing. Land-surface change results from human activities or natural processes like floods, droughts, and wildfires, and many of these change processes are observable in satellite imagery. The growing historical catalog of satellite images allows...Land Cover Trends
Land Cover Trends was a research project focused on understanding the rates, trends, causes, and consequences of contemporary U.S. land use and land cover change. The project spanned from 1999 to 2011. The research was supported by the Climate and Land Use Change Research and Development Program of the U.S. Geological Survey (USGS) and was a collaborative effort with the U.S. Environmental...Integration of Land Cover Trends Field Photography with an Online Map Service
The USGS National Land Cover Trends Project has the largest repository of field photos at the USGS (over 33,000 photos). Prior to CDI funding, Land Cover Trends had limited funding to make the national collection of photos available online for researchers, land managers, and citizens. The goal of this CDI project was to add geotags and keywords to the digital copies of each field photo and make thAssessing the Vulnerability of Dryland Ecosystems to Drought in the Western U.S.
In the western U.S., rising temperatures and pronounced drought conditions pose significant challenges to public land managers. Widespread declines of multiple plant species have already been observed, providing insight into what the future could look like for vegetation in the region as conditions are projected to become warmer and drier. To understand how vulnerable western ecosystems are to droLinking Extreme Storms to Changes in Precipitation, Ecosystems, and Wildfire Patterns in the Sierra Nevada
The majority of the West Coast’s most extreme storms have been linked to atmospheric rivers, a meteorological phenomenon in which large amounts of moisture are carried in narrow bands from over the Pacific Ocean to western North America. While weak atmospheric rivers are critical providers of winter rain and snow, stronger events can cause extreme flooding, mudslides, and avalanches – leading to p... - Data
County-level maps of cropland surface water inundation measured from Landsat and MODIS
This dataset represents a summary of potential cropland inundation for the state of California applying high-frequency surface water map composites derived from two satellite remote sensing platforms (Landsat and Moderate Resolution Imaging Spectroradiometer [MODIS]) with high-quality cropland maps generated by the California Department of Water Resources (DWR). Using Google Earth Engine, we examiNational Surface Water Maps using Daily MODIS Satellite Data for the Conterminous United States, 2003-2019
Members from the U.S. Geological Survey (USGS) Patterns in the Landscape - Analyses of Cause and Effect (PLACE) team are releasing monthly surface water maps for the conterminous United States (U.S.) from 2003 through 2019 as 250-meter resolution geoTIFF files. The maps were produced using the Dynamic Surface Water Extent (DSWE) algorithm applied to daily Moderate Resolution Imaging SpectroradiomeDSWEmod surface water map composites generated from daily MODIS images - California
USGS researchers with the Patterns in the Landscape ? Analyses of Cause and Effect (PLACE) project are releasing a collection of high-frequency surface water map composites derived from daily Moderate Resolution Imaging Spectroradiometer (MODIS) imagery. Using Google Earth Engine, the team developed customized image processing steps and adapted the Dynamic Surface Water Extent (DSWE) to generate sSpatially-explicit land-cover scenarios of federal lands in the northern Great Basin, 2018-2050
As part of a 2018 Northwest Climate Adaptation and Science Center project, USGS researchers are releasing a series of spatially-explicit land-cover projections for the period 2018-2050 covering part of the northern Great Basin (Beaty Butte Herd Management Area, Hart Mountain National Antelope Refuge, and Sheldon National Refuge). The dataset contains an empirically-based business-as-usual (BAU) anImplementation of a Surface Water Extent Model using Cloud-Based Remote Sensing - Code and Maps
This data release comprises the raster data files and code necessary to perform all analyses presented in the associated publication. The 16 TIF raster data files are classified surface water maps created using the Dynamic Surface Water Extent (DSWE) model implemented in Google Earth Engine using published technical documents. The 16 tiles cover the country of Cambodia, a flood-prone country in SoPhenology pattern data indicating recovery trajectories of ponderosa pine forests after high-severity fires
This tabular, machine-readable CSV file contains annual phenometrics at locations in ponderosa pine ecosystems across Arizona and New Mexico that experienced stand-clearing, high-severity fire. The locations represent areas of vegetative recovery towards pre-fire (coniferous/pine) vegetation communities or towards novel grassland, shrubland, or deciduous replacements. Each sampled area is associatDatasets for analyzing stream gage discharge and Landsat imagery integration in the greater Central Valley, California from 1984 to 2015
This data release comprises the data files and code necessary to perform all analyses presented in the associated publication. The *.csv data files are aggregations of water extent on the basis of the European Commission's Joint Research Centre (JRC) Monthly Water History database (v1.0) and the Dynamic Surface Water Extent (DSWE) algorithm. The shapefile dataset contains the study area 8-digitData - Forest harvest patterns on private lands in the Cascade Mountains, Washington, USA
Forests in Washington State generate substantial economic revenue from commercial timber harvesting on private lands. To investigate the rates, causes, and spatial and temporal patterns of forest harvest on private tracts throughout the central Cascade Mountain area, we relied on a new generation of annual land-use/land-cover (LULC) products created from the application of the Continuous Change DeData on influence of atmospheric rivers on vegetation productivity and fire patterns in the southwestern US
In the southwestern US, the meteorological phenomenon known as atmospheric rivers (ARs) has gained increasing attention due to its strong connections to floods, snowpacks and water supplies in the West Coast states. Relatively less is known about the ecological implications of ARs, particularly in the interior Southwest, where AR storms are less common. To address this gap, we compared a chronologLand Cover Trends Dataset, 2000-2011
U.S. Geological Survey scientists, funded by the Climate and Land Use Change Research and Development Program, developed a dataset of 2006 and 2011 land use and land cover (LULC) information for selected 100-km2 sample blocks within 29 EPA Level 3 ecoregions across the conterminous United States. The data was collected for validation of new and existing national scale LULC datasets developed from - Multimedia
- Publications
Filter Total Items: 43
Using Landsat and MODIS satellite collections to examine extent, timing, and potential impacts of surface water inundation in California croplands☆
The state of California, United States of America produces many crop products that are both utilized domestically and exported throughout the world. With nearly 39,000 km2 of croplands, monitoring unintentional and intentional surface water inundation is important for water resource management and flood hazard readiness. We examine inundation dynamics in California croplands from 2003 to 2020 by iAuthorsBritt Windsor Smith, Christopher E. Soulard, Jessica J. Walker, Anne WeinAnalysis of surface water trends for the conterminous United States using MODIS satellite data, 2003–2019
Satellite imagery is commonly used to map surface water extents over time, but many approaches yield discontinuous records resulting from cloud obstruction or image archive gaps. We applied the Dynamic Surface Water Extent (DSWE) model to downscaled (250-m) daily Moderate Resolution Imaging Spectroradiometer (MODIS) data in Google Earth Engine to generate monthly surface water maps for the contermAuthorsRoy Petrakis, Christopher E. Soulard, Eric K. Waller, Jessica J. WalkerDSWEmod - The production of high-frequency surface water map composites from daily MODIS images
Optical satellite imagery is commonly used for monitoring surface water dynamics, but clouds and cloud shadows present challenges in assembling complete water time series. To test whether the daily revisit rate of Moderate Resolution Imaging Spectroradiometer (MODIS) satellite imagery can reduce cloud obstruction and improve high-frequency surface water mapping, we compared map results derived froAuthorsChristopher E. Soulard, Eric Waller, Jessica J. Walker, Roy Petrakis, Britt Windsor SmithSolar and sensor geometry, not vegetation response, drive satellite NDVI phenology in widespread ecosystems of the western United States
Satellite-derived phenology metrics are valuable tools for understanding broad-scale patterns and changes in vegetated landscapes over time. However, the extraction and interpretation of phenology in ecosystems with subtle growth dynamics can be challenging. US National Park Service monitoring of evergreen pinyon-juniper ecosystems in the western US revealed an unexpected winter-peaking phenologicAuthorsJodi R. Norris, Jessica J. WalkerApplication of empirical land-cover changes to construct climate change scenarios in federally managed lands
Sagebrush-dominant ecosystems in the western United States are highly vulnerable to climatic variability. To understand how these ecosystems will respond under potential future conditions, we correlated changes in National Land Cover Dataset “Back-in-Time” fractional cover maps from 1985-2018 with Daymet climate data in three federally managed preserves in the sagebrush steppe ecosystem: Beaty ButAuthorsChristopher E. Soulard, Matthew B. RiggeImplementation of a surface water extent model in Cambodia using cloud-based remote sensing
Mapping surface water over time provides the spatially explicit information essential for hydroclimatic research focused on droughts and flooding. Hazard risk assessments and water management planning also rely on accurate, long-term measurements describing hydrologic fluctuations. Stream gages are a common measurement tool used to better understand flow and inundation dynamics, but gage networksAuthorsChristopher E. Soulard, Jessica J. Walker, Roy E. PetrakisPhenology patterns indicate recovery trajectories of ponderosa pine forests after high-severity fires
Post-fire recovery trajectories in ponderosa pine (Pinus ponderosa Laws.) forests of the US Southwest are increasingly shifting away from pre-burn vegetation communities. This study investigated whether phenological metrics derived from a multi-decade remotely sensed imagery time-series could differentiate among grass, evergreen shrub, deciduous, or conifer-dominated replacement pathways. We focAuthorsJessica J. Walker, Christopher E. SoulardLandsat time series assessment of invasive annual grasses following energy development
Invasive annual grasses are of concern in many areas of the Western United States because they tolerate resource variability and have high reproductive capacity, with propagules that are readily dispersed in disturbed areas like those created and maintained for energy development. Early-season invasive grasses “green up” earlier than the most native plants, producing a distinct pulse of greennessAuthorsMiguel L. Villarreal, Christopher E. Soulard, Eric WallerIntegrating stream gage data and Landsat imagery to complete time-series of surface water extents in Central Valley, California
Accurate monitoring of surface water location and extent is critical for the management of diverse water resource phenomena. The multi-decadal archive of Landsat satellite imagery is punctuated by missing data due to cloud cover during acquisition times, hindering the assembly of a continuous time series of inundation dynamics. This study investigated whether streamflow volume measurements could bAuthorsJessica J. Walker, Christopher E. Soulard, Roy E. PetrakisRemoving rural roads from the National Land Cover Database to create improved urban maps for the United States, 1992-2011
Quantifying change in urban land provides important information to create empirical models examining the effects of human land use. Maps of developed land from the National Land Cover Database (NLCD) of the conterminous United States include rural roads in the developed land class and therefore overestimate the amount of urban land. To better map the urban class and understand how urban lands chanAuthorsChristopher E. Soulard, William Acevedo, Stephen V. StehmanForest harvest patterns on private lands in the Cascade Mountains, Washington, USA
Forests in Washington State generate substantial economic revenue from commercial timber harvesting on private lands. To investigate the rates, causes, and spatial and temporal patterns of forest harvest on private tracts throughout the Cascade Mountains, we relied on a new generation of annual land-use/land-cover (LULC) products created from the application of the Continuous Change Detection andAuthorsChristopher E. Soulard, Jessica J. Walker, Glenn E. GriffithProjecting community changes in hazard exposure to support long-term risk reduction: A case study of tsunami hazards in the U.S. Pacific Northwest
Tsunamis have the potential to cause considerable damage to communities along the U.S. Pacific Northwest coastline. As coastal communities expand over time, the potential societal impact of tsunami inundation changes. To understand how community exposure to tsunami hazards may change in coming decades, we projected future development (i.e. urban, residential, and rural), households, and residentsAuthorsBenjamin M. Sleeter, Nathan J. Wood, Christopher E. Soulard, Tamara S. Wilson - Software
DSWE_GEE v1.0.0
Code for implementation of the Dynamic Surface Water Extent algorithm in Google Earth Engine. Multiple scripts allow the creation of single-scene or composited Dynamic Surface Water Extent (DSWE) images from Landsat and MODIS data. All code is written for use in the JavaScript API. - News