Eyes on Earth: Land Change
The Earth’s surface is constantly changing. Some events are fast like earthquakes and tsunamis; others are slow like forest recovery and urban growth. Listen to episodes about land change here.
Episode 113 – EROS Science Leader’s Vision
Terry Sohl helped develop the National Land Cover Database, NLCD, when he first arrived, and now he’s overseeing significant improvements to the widely used product. But that’s just one part of his new role. In this episode, Sohl provides an overview of the science efforts at EROS and how artificial intelligence and machine learning help scientists focus more on the work that helps society. He also shares his vision for the future.
Guest: Terry Sohl, Chief of the USGS EROS Integrated Science and Applications Branch
Host: Jane Lawson (contractor for USGS EROS)
Release date: Monday, February 26, 2023
Episode 107 – EROS 50th: Land Cover, Part 2
The National Land Cover Database (NLCD) has a long history as the definitive U.S. land cover product. But the newer Land Change Monitoring, Assessment and Projection (LCMAP) effort takes a longer look back in time. In this episode, we learn how the two projects at EROS, both based on 30-meter resolution Landsat satellite data, are merging to bring the strengths of each to future data releases under the NLCD name. This is the second of two episodes discussing land cover work at EROS, with the first focused on earlier pioneering efforts.
Guests: Terry Sohl, Research Physical Scientist at USGS EROS, and Jon Dewitz, Physical Scientist at USGS EROS
Host: Jane Lawson (contractor for USGS EROS)
Release date: Monday, November 13, 2023
Episode 106 – EROS 50th: Land Cover, Part 1
Several decades ago, EROS employees were pioneers in land cover mapping—turning satellite imagery into a record of what covers the land, from farmland to forest to urban areas. National and global datasets with a variety of uses resulted from these efforts. In this episode, we explore some of this history, along with how it benefited people at the time and the mapping efforts that would follow. Our next episode will look at two modern efforts at EROS, NLCD and LCMAP, and how their strengths are merging for the next generation of land cover and change products.
Guest: Jesslyn Brown, longtime research geographer at USGS EROS
Host: Jane Lawson (contractor for USGS EROS)
Release date: Monday, October 30, 2023
Episode 102 – LANDFIRE 2022 Update
LANDFIRE, short for Landscape Fire and Resource Management Planning Tools, is a key national data source for the management of wildfires, management of the plant materials that fuel fires, and planning for prescribed fires across all 50 states and the U.S. territories. The data products, partly derived from satellite imagery, are generated at EROS through a partnership between the Department of the Interior and the U.S. Forest Service, with The Nature Conservancy as an additional partner. In this episode, we learn about how LANDFIRE is including more up-to-date information than ever about disturbances to the land.
Guest: Inga La Puma, a USGS EROS contractor at the time of the recording but now with the USDA Forest Service, still as a LANDFIRE fire scientist
Host: Jane Lawson (contractor for USGS EROS)
Release date: Monday, August 28, 2023
Episode 96 – Generational Science
In this episode, we talk with Peder Nelson about generational science and the responsibility we have to future generations to study our changing planet. It takes more than just data to make sense of land change. And while remote sensing scientists work with the deep archive of Landsat and other land data available from the USGS EROS Center, everyone can put themselves on the timeline of Landsat data. Citizen science projects allow anyone to participate in the observations that help us understand the world around us.
Guest: Peder Nelson, Oregon State University
Host: Tom Adamson (contractor for USGS EROS)
Release date: Tuesday, June 20, 2023
Episode 84 – Hurricane Disturbance Mapping
When disaster strikes, near-real-time images of its effects can be invaluable. In this episode, we learn about how a newly developed system using the Harmonized Landsat Sentinel-2 dataset and artificial intelligence was put to the test when Hurricane Ian tore through Florida in late September 2022. By comparing pre-storm and post-storm imagery, the system quickly flagged anomalies statewide such as brightness, which could indicate exposed sand or bare land after a hurricane. Harmonized Landsat Sentinel-2 data is available through the Land Processes Distributed Active Archive Center, or LP DAAC for short, located at EROS, which is also home to the entire Landsat archive.
Guest: Zhe Zhu, University of Connecticut’s Global Environmental Remote Sensing Laboratory and Landsat Science Team
Host: Jane Lawson
Release date: Monday, November 21, 2022
Episode 75 – Mapping Dust Sources Worldwide
Clouds of dust kicked up in places like the Sahara can travel thousands of miles across the planet. We can see those clouds in satellite imagery, but we don’t typically know much about the composition of that dust. That’s a huge blind spot, because those unknown characteristics—such as the particles’ lightness or darkness—have an impact on what they do. The warming and cooling of the atmosphere, snow melt, ocean or rain forest fertilization, and even cloud formation can all be affected by dust cloud composition. Mapping those dust sources is the focus of the Earth Surface Mineral Dust Source Investigation, or EMIT, which will be supported by NASA’s Land Processes Distributed Active Archive Center (LP DAAC), which is located at the USGS EROS Center. On this episode of Eyes on Earth, we hear about the importance of the mission from three members of the EMIT Science Team.
Guests: Raymond Kokaly, USGS; David Thompson, NASA Jet Propulsion Laboratory (JPL); Philip Brodrick, NASA JPL
Host: John Hult
Producer: John Hult
Release date: June 15, 2022
Episode 72 – Northward Shift of the Boreal Forest
The boreal forest, or taiga, stretches across nearly 5.7 million square miles in the northern latitudes. That’s nearly a quarter of all forested lands in the world. This sprawling biome also happens to be one of the most rapidly shifting in the face of climate change. Many studies have suggested that the taiga tree line is moving northward as temperatures warm worldwide, edging itself into the colder tundra. On this episode of Eyes on Earth, we hear from Professor Logan Berner, part of team at Northern Arizona University’s Global Earth Observation and Dynamics of Ecosystems (GEODE) Lab that used USGS Landsat satellite data to track and quantify the northward shift of the boreal tree line.
Guests: Logan Berner, assistant research professor in the School of Informatics, Computing, and Cyber Systems (SICCS), Northern Arizona University
Host: John Hult
Release date: April 18, 2022
Episode 71 – Blue Oak Forests of California
In this episode of Eyes on Earth, we zero in on the use of USGS Land Change Monitoring, Assessment, and Projection (LCMAP) products to examine the effects of drought on California’s Blue Oaks. LCMAP datasets are built from Landsat data and reveal the land cover and change of every pixel in the conterminous United States, dating back to 1985. In this case, LCMAP helped identify areas of declines and losses of the Blue Oak trees that are native to California and found in the foothills surrounding the central valley and along the coast.
Guests: Francis Dwomoh, contractor and landscape ecologist, USGS EROS Center
Host: Jane Lawson
Release date: April 4, 2022
Episode 69 - Thirty Years of Land Change in the U.S.
Land change is a constant. Even land areas that see little major change can see disruptions from storms, heat waves, wildfires, or invasive species. But major changes aren't uncommon, either. Each year in the U.S., farm fields become tracts of suburban homes, wetlands become more permanent bodies of water, and shrublands burn to be replaced with grasslands. A team of researchers with the USGS Land Change Monitoring, Assessment, and Projection initiative (LCMAP) recently released a study documenting land cover class change from 1985-2016. On this episode of Eyes on Earth, we talk to the study’s lead author about what they learned about land change, and about how land change ties into policy, economic trends, weather patterns and more.
Guest: Roger Auch, Research Physical Geographer, USGS EROS Center
Host: John Hult
Release date: March 7, 2022
Episode 66 - Exotic Annual Grasses
The rangelands of the western United States are changing more quickly than many other parts of the lower 48. Miles upon miles of the area or semi-arid landscapes in states like Idaho, Montana and Nevada are now carpeted by fire fueling invasive grasses. Cheatgrass is the most prevalent, which is troublesome for several reasons. First off, it greens up and browns down really quickly, leaving a layer of tinder-like vegetation. In many areas, it fills in the formerly barren spaces between thicker bunchgrasses and sagebrush, which in turn helps fires move rapidly from fuel source to fuel source. On this episode of Eyes on Earth, we hear from the USGS EROS teams who use satellite data to map exotic annual grasses and a researcher who uses those maps to create monthly grass abundance estimates for firefighters and land managers.
Guests: Stephen Boyte, USGS EROS research physical scientist, Devendra Dahal, USGS EROS contractor, Matt Reeves, USDA Forest Service ecologist
Host: John Hult
Release date: January 24, 2022
Episode 54 – National Land Cover Database 2019
The National Land Cover Database, or NLCD, was the first and remains the most well-known set of satellite-based land cover mapping products released by EROS. It sorts the each 30-by-30-meter plot of land in the United States into a land cover class, such as cropland, pasture, high-intensity developed, deciduous forest, and the like. It also includes information on impervious urban surfaces, forest canopy cover and more. For this episode of Eyes on Earth, we hear about the latest release, NLCD 2019, the importance of land cover, and how mapping teams at EROS work together to produce accurate, reliable information.
Guest: Jon Dewitz, USGS National Land Cover Database manager
Host: John Hult
Release date: July 12, 2021
Episode 46 – Deforestation and Forest Degradation
Deforestation is a significant concern for many parts of the globe, particularly in places like the rainforests of the Amazon or the Congo. Scientists, governments, and non-governmental organizations turn to satellite data to track deforestation, as well as to set targets for improvement. On this episode of Eyes on Earth, we hear from a remote sensing specialist with the U.S. Forest Service who develops algorithms that sift through satellite data to capture not only deforestation events, but the more subtle degradation events that have an impact on forest health.
Guest: Dr. Eric Bullock, U.S. Forest Service
Host: John Hult
Release date: March 22, 2021
Episode 42 – Rangelands of the U.S.
The extensive rangelands across the Western United States are threatened by invasive grasses, climate change, and altered fire regimes that can disturb the landscape. The largely semi-arid lands are also important for the survival of species that need undisturbed sagebrush ecosystems to thrive. But most satellite-based land cover datasets don’t offer the kind of detail needed to track small but ecologically meaningful shifts in vegetation that can alter fire regimes and improve habitats. In this episode of Eyes on Earth, we hear about how new EROS data products help fill in that gap.
Guest: Matt Rigge, Research Physical Scientist, USGS EROS Center
Host: John Hult
Release date: January 25, 2021
Episode 38 – Time Series Analysis with Landsat
In the past, remote sensing scientists looked for change on the Earth’s surface primarily by comparing one Landsat image to another. Today, open access to Landsat data, high-performance and cloud computing capabilities and sophisticated algorithms can be used to scan the entirety of the archive for change, enabling researchers to learn more about how the landscape shifts over time. On this episode of Eyes on Earth, Landsat Science Team member Dr. Curtis Woodcock shares his thoughts on time series analysis, the future of remote sensing and his hopes for the Landsat program.
Guest: Dr. Curtis Woodcock, Boston University
Host: Steve Young
Release date: November 16, 2020
Episode 33 – Global Land Change
Mapping land cover across the United States using Landsat satellite data is a difficult, time-intensive job, but there are jobs far larger. Matt Hansen, a Maryland-based professor and member of the Landsat Science Team focuses his efforts on mapping land cover and change on a global scale. In this episode of Eyes on Earth, we hear from Matt on how he and his team use the Landsat archive to map change at such a wide scale.
Guest: Matt Hansen, Department of Geographical Sciences at the University of Maryland, College Park
Host: Steve Young
Release date: September 8, 2020
Episode 29 – Tracking Landscape Change with LCMAP
The U.S. Geological Survey took a bold step toward documenting change across the landscape with the launch of the first Landsat satellite in 1972. Since then, it’s collected nearly five decades of imagery. But it takes more than just imagery to understand change. It takes time, effort—and serious computing horsepower. The USGS Land Change Monitoring, Assessment, and Projection (LCMAP) initiative aims to use the full Landsat record to track change in long-term landscape conditions. In this episode, we hear about LCMAP and what its 33-year product suite can tell us about change in the U.S.
Guests: Jesslyn Brown and Jennifer Rover, Research Geographers, USGS EROS
Host: John Hult
Release date: July 13, 2020
Episode 25 - Rising Seas
Sea levels are rising globally. In some places, it is rising more than others, threatening communities and people as storm surges reach further inland and inundate more land. Landsat satellites used with other Earth-observing platforms enable EROS scientists to model the elevation of coastal shores, giving decision makers valuable information to use in preparing for the rising seas. In this episode of Eyes on Earth, we talk to one of the scientists about the utility of EROS’ elevation models.
Guests: Dean Gesch, USGS
Host: Steve Young
Release date: May 18, 2020
Episode 16 – Predictive Modeling
Land cover and land use across the United States are the culmination of a complex web of interwoven factors: Climate, landscape types, and economic factors among them. Remotely-sensed data from satellites like Landsat and a variety of other sources are useful for documenting and monitoring land cover and land use. When used alongside other data sources, however, remote sensing data can offer a glimpse at future land use under a range of scenarios.
Guests: Terry Sohl, Research Physical Scientist, EROS
Host: Steve Young
Release date: Feb. 10, 2020
Episode 13 – Land Use
Scientists at EROS use tools like Landsat to produce land cover maps, which tell us if landscapes are rural or urban, cropped or forested, wetland or shrubland. Those maps help scientists at EROS and around the U.S. study the impact of changes in land use on not just landscapes, but on ecosystems, patterns of resource use, wildlife habitat, and much more. In this episode, we learn about the basics of land use and land cover study research from Geographer Roger Auch.
Guest: Roger Auch, Research Geographer
Host: Steve Young
Producer: Brian Hauge
Release date: Dec. 30, 2019
Episode 12 – Plant Health via Satellite (NDVI)
A farmer at the foot of a corn stalk can tell how well the plant is faring. That same farmer might survey his entire field for crop health. But assessing the health of crops or forests at regional, national, and international scales requires remote sensing, most often via satellite. In this episode of Eyes on Earth, we talk to Jesslyn Brown about the Normalized Difference Vegetation Index (NDVI), a tool that uses the broader electromagnetic spectrum to estimate plant health.
Guests: Jesslyn Brown, Research Physical Scientist
Host: John Hult
Release date: Dec. 16, 2019
Episode 3 - National Land Cover Database
Sorting Landsat data into an accurate and reliable record of land cover in the United States is one of the most important jobs at EROS. This episode explores the what, how, and why of the National Land Cover Database (NLCD).
Guest: Collin Homer, NLCD Program Director
Host: John Hult
Producer: John Hult
Release date: Sept. 9, 2019
Episode 2 - Chernobyl
When the Chernobyl Nuclear Power Plant's Reactor 4 disaster struck Ukraine on April 26, 1986, Landsat satellites were among the first to capture visual evidence of its widespread impact. The disaster focused the world's attention on the value of remote sensing.
Guest: John Dwyer, EROS Science Branch Chief
Host: Steve Young
Release date: Sept. 9, 2019