Christopher Soulard
Biography
Chris Soulard started with the U.S. Geological Survey in 2002 and has been with the Western Geographic Science Center since 2005. Early in his career, Chris applied his knowledge of remote sensing into projects focusing on multi-temporal change analyses using Landsat imagery and aerial photography, most notably the Land Cover Trends Project. Chris has since expanded his research scope to include 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. Chris Soulard serves as the Principal Investigator of the PLACE Project (Patterns in the Landscape – Analyses of Cause and Effect).
Science and Products
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...
Web 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...
Patterns in the Landscape – Analyses of Cause and Effect
For two decades, USGS scientists with the Land Cover Trends team have used satellite data to study landscape change across the United States. Increasingly, research is focused on understanding why change occurs. Insights into the underlying causes of shifts in land use and land cover (LULC) will allow managers and stakeholders to make more informed decisions about how to respond to future...
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...
Solar 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...
Norris, Jodi R.; Walker, Jessica J.Application 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...
Soulard, Christopher E.; Rigge, Matthew B.Implementation 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...
Soulard, Christopher E.; Walker, Jessica J.; Petrakis, Roy E.Phenology 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...
Walker, Jessica J.; Soulard, Christopher E.Landsat 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...
Villarreal, Miguel L.; Soulard, Christopher E.; 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...
Walker, Jessica J.; Soulard, Christopher E.; Petrakis, Roy E.Removing 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...
Soulard, Christopher E.; Acevedo, William; Stehman, Stephen V.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 Cascade Mountains, we relied on a new generation of annual land-use/land-cover (LULC) products created from the...
Soulard, Christopher E.; Walker, Jessica J.; Griffith, Glenn E.Projecting 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,...
Sleeter, Benjamin M.; Wood, Nathan J.; Soulard, Christopher E.; Wilson, TamaraHarmonization of forest disturbance datasets of the conterminous USA from 1986 to 2011
Several spatial forest disturbance datasets exist for the conterminous USA. The major problem with forest disturbance mapping is that variability between map products leads to uncertainty regarding the actual rate of disturbance. In this article, harmonized maps were produced from multiple data sources (i.e., Global Forest Change, LANDFIRE...
Soulard, Christopher E.; Acevedo, William; Cohen, Warren B.; Yang, Zhiqiang; Stehman, Stephen V.; Taylor, Janis L.Influence of atmospheric rivers on vegetation productivity and fire patterns in the southwestern U.S.
In the southwestern U.S., 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...
Albano, Christine M.; Dettinger, Michael D.; Soulard, Christopher E.Data 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...
Albano, Christine M.; Dettinger, Michael; Soulard, Christopher E.Empirically-Driven Land Cover Change Scenarios in Federal Lands
This article is part of the Fall 2020 issue of the Earth Science Matters Newsletter.
Integrating stream gage data and Landsat imagery to complete surface water records
This article is part of the Spring 2020 issue of the Earth Science Matters Newsletter.
Improved Urban Maps for the United States
This article is a part of the Fall 2019 issue of the Earth Science Matters Newsletter.
Newly Released Photo Catalog Puts US Landscapes On Exhibit
The U.S. Geological Survey announced today that it has made part of a huge national repository of geographically referenced USGS field photographs publicly available. USGS geographers developed a simple, easy-to-use mapping portal called the Land Cover Trends Field Photo Map.