Marking 50 Years of Landsat

It’s hard for us to care about problems we can’t see.

It’s hard for us to manage problems we can’t measure.

That’s why I started SkyTruth – to make environmental changes visible to everyone.

And that’s why I was so moved by a recent encounter. Last week, after the Our Ocean conference had wrapped up, I found myself having dinner in the lovely home of a new friend of SkyTruth. Our little party included Tom Udall, senator from New Mexico.   When he heard about SkyTruth, he asked me if we used Landsat images.  I told him I thought the Landsat satellite program was one of NASA’s most important success stories; and that we use Landsat images on a daily basis at SkyTruth for environmental monitoring.

His eyes lit up and he told me something I hadn’t realized: his father, Stewart Udall, former Secretary of the Interior, was one of the key drivers in the origin story of the Landsat program. In the mid-1960s the head of the US Geological Survey, William Pecora, convinced Secretary Udall that the nation should launch a fleet of earth-observing satellites. In 1966, Udall announced the program – a politically savvy move that prompted NASA to get involved and take charge of the design, construction, launch and operation of the satellites.  In late 1971, the first Landsat satellite was launched, ushering in the era of space-based remote sensing that is thriving today.  Landsat satellites have been operating continuously since Landsat-1, with Landsat-7 and Landsat-8 currently carrying the torch.

More than 4 million Landsat images of the earth have been collected, with hundreds of new images added to that tremendous archive every day.  This provides a priceless dataset for measuring – and showing – how landscapes and ecosystems have changed over the past 45 years, a time of skyrocketing population growth and human-caused disruption of interconnected natural processes and systems that we’re racing to fully understand.  Landsat imagery provides a critical tool for investigating and understanding the many ways we’re impacting our own life support systems.

Just a few examples:

  • The outstanding Global Forest Watch program, a partnership of World Resources Institute and Google, powered by analytical algorithms developed at the University of Maryland, uses Landsat to make a complete global map of forest cover every year. Users can sign up to get automatic alerts whenever a deforestation event is detected in their area of interest. Companies that use wood products are pledging to get illegal logging out of their supply chains, and are using Global Forest Watch to verify their progress. Governments are monitoring logging concessions and protected areas to ensure companies are complying with regulations. This project has provided plenty of inspiration for our own Global Fishing Watch project with Oceana and Google.
  • Our project — in partnership with Appalachian Voices, Duke University, and Google — to map the “footprint” of mountaintop removal mining for coal in Appalachia is systematically analyzing Landsat images to generate a geospatial database of mining-disrupted land. We’re taking advantage of the fact that Google is hosting the entire archive of Landsat images and is giving us free access to this massive cloud storage through a powerful cloud-computing tool called Earth Engine. This data has already resulted in more than half a dozen peer-reviewed scientific studies quantifying the human health and environmental consequences of mountaintop mining, and has moved the policy needle in a major way.  It’s our hope that the annually updated map will serve as a focal point for envisioning what we want Appalachia to look like in the future, and tool for planning how we’re going to get there from here.
  • TIMElapse, a collaboration between TIME and Google, lets you see 30 years of change – everywhere on the planet – at the click of a mouse. Give it a try, and be amazed. And in some cases, alarmed.

September 21 marked the 50th anniversary of Stewart Udall’s announcement that launched the Landsat program.  His son Tom was guest of honor, and should be very proud of this piece of his father’s impressive legacy.  We certainly are grateful for his vision: “a program aimed at gathering facts about the natural resources of the earth from earth-orbiting satellites.”  This is an example of something government can do well: investing in infrastructure that broadly benefits society, and provides a stable platform for the development of businesses and economic activity.  Landsat is the data equivalent of the interstate highway system, a public good that has spawned a thriving for-profit remote sensing industry in the US and beyond.

We’re looking forward to the uninterrupted continuation of the Landsat program and (at least) another 50 years of systematic Earth observation, because it’s needed now more than ever.

Global Fishing Watch Goes Live

SkyTruth is helping make the world’s oceans a little less mysterious and a great deal more transparent with the public beta release of Global Fishing Watch, announced today at the Our Ocean Conference in Washington, DC. Actor and ocean advocate Leonardo DiCaprio announced in his remarks to the conference that Global Fishing Watch is now free and open to the public, and U.S. Secretary of State John Kerry personally received a demonstration of the tool from the Oceana, SkyTruth, and Google team.

In partnership with Oceana and Google, Global Fishing Watch was designed, developed, and tested by SkyTruth to enable users to map and analyze all of the world’s trackable commercial fishing activity. Global Fishing Watch is the world’s first dynamic, global, near real-time measure of fishing activity.

SkyTruth is proud to make this tool available to the public, enabling researchers, advocates, regulators, consumers, and industry to shine a light on fishing activity and pierce the fog of uncertainty surrounding global seafood supply chains.


Above: With Global Fishing Watch, users will easily be able to visualize when and where fishing activity occurs. This visualization depicts six months of fishing activity by three of the world’s most prolific fleets – fishing vessels flagged to China, Japan, and Spain.

Our oceans are under pressure from overfishing, and recent stories about crime on the high seas have riveted the public’s attention. Global Fishing Watch gives legal operators a way to show the world they’re playing by the rules and that they deserve access to premium seafood markets. Global Fishing Watch provides regulators with an easy way to visualize their own data, and GFW will empower citizens and indigenous peoples to hold regulators accountable for enforcing the rules.

Oceana, SkyTruth, and Google unveiled the prototype in November 2014 at the IUCN World Parks Congress in Sydney, Australia. Today, Global Fishing Watch unlocks the power of machine-learning, mapping, and a near real-time feed of satellite data to anyone with a modern computer and decent internet connection.

When Vessels Report False Locations

Lu Yan Yuan Yu 10 TPY9 offset GE inset logo

The red tracks show the broadcast position of the Lu Yan Yuan Yu 10 apparently transiting across Antarctica (inset). The yellow tracks show its true location along the coast of South America passing through the Strait of Magellan and into port at Lima, Peru.

Occasionally, the AIS messages transmitted from a ship provide a location that makes no sense, say, in the middle of the Antarctic or over a mountain range. In such cases, either the AIS transponder has malfunctioned, the data got scrambled in transmission, or the system has been tampered with in a deliberate attempt to disguise the vessel’s location. Read more

Advancing the Science and Technology of “Sky Truthing”: SkyTruth in the scientific literature

It has been almost 15 years since we first launched SkyTruth with the belief that sharing images of habitat loss and environmental change would not only contribute to public awareness of the human footprint on our earth, but would become a valuable resource for scientific research and discussion. As a scientist who comes from a family of scientists, SkyTruth President John Amos is driven by a deep-rooted interest in seeking evidence-based truth. Whether that evidence unveils nefarious behavior by commercial interests and colluding government entities, or debunks myths of over-eager watchdogs crying wolf, our job is to put it out there for public scrutiny.

So, it is immensely gratifying when our work is used to advance scientific knowledge of the health and environmental ramifications of human activity. Our data and analysis has contributed to a variety of studies and been cited in numerous research papers on issues ranging from mountaintop removal (MTR) mining, offshore oil spills, the effects of fracking and commercial fisheries.

“I’m incredibly proud that what we produce is helping scientists do meaningful work,” says John, “and that it’s resulted in the kind of impact it has and the kind of outcomes we’ve seen.”

Here’s a sampling of some of the scientific and academic publications to which our work has contributed.


Through the Global Fishing Watch Research program, our analysts work directly with world renowned experts and academic researchers, applying our data to some of the most pressing issues facing global fishing and ocean sustainability.

Among the first fruits of those partnerships is the article “Ending Hide and Seek in the Oceans” published in Science magazine in April, 2016. Co-authored by Doug McCauley of University of California, Santa Barbara, our chief technology officer, Paul Woods, our data analyst Bjorn Bergman and other collaborators.

Two months later, that article was cited in a paper published in PLoS ONE titled “Improving Fishing Pattern Detection from Satellite AIS Using Data Mining and Machine Learning.” Authored by our research partners from Dalhousie University in Nova Scotia, Kristina Boerder, Boris Worm and colleagues, the paper outlines work that is directly contributing to and being built up by our Global Fishing Watch computer models.


Having been responsible for revealing the extent of the BP Deepwater Horizon oil spill in 2010, SkyTruth’s analysis of the volume of the slick and the daily rate of flow has made its way into the general scientific literature on analysis of the spill and its impacts.

Our direct contributions to the literature includes an article co-authored by SkyTruth president John Amos along with Elliot Norse, president of Marine Conservation Biology International. Titled “Impacts, Perception, and Policy Implications of the BP/Deepwater Horizon Oil and Gas Disaster,” the article was published in the November 2010 issue of Environmental Law Reporter’s News & Analysis.

That article was later adapted into the article “Deepwater Horizon Revisited” and published in Earth Imaging Journal.

Examples of outside research papers that included our data and analysis include:

A paper by Ian MacDonald of Florida State University in the journal Significance titled Deepwater Disaster: how the oil spill estimates got it wrong.”

A paper in the January 2013 issue of the journal Sustainable Engineering authored by researcher Konstantin A. Korotenko of the Russian Academy of Sciences P.P.Shirshov Institute of Oceanology and his colleagues. The paper titled “Modeling 3-D Transport and Dispersal of Oil Plume Released During BP/Horizon Accident in the Gulf of Mexico in 2010included a cumulative slick footprint of the spill created by overlaying all of the oil slicks mapped by SkyTruth on satellite images taken between April 25 and July 16, 2010.

Shortly after the BP disaster, in April of 2011, we led the formation of The Gulf Monitoring Consortium, an alliance of non-profits that collects, analyzes and publishes images and other information to investigate and expose pollution incidents that occur in the Gulf of Mexico and Gulf Coast region.

We released a summary of our findings over the first six months, Report on Activities from April 2011 to October 2011, that documented under reporting and lack of reporting of oil spill by responsible parties and inconsistencies in collection and publication of oil spill reports by National Response Center.

That report has been cited in numerous research papers including, most recently, an article in the January 16 issue of the journal Nature authored by Louisiana State University department of entomology researcher Claudia Husseneder and colleagues titled “Impact of the 2010 Deepwater Horizon Oil Spill on Population Size And Genetic Structure of Horse Flies in Louisiana Marshes.”

In August 2013, we issued another report titled Lessons from Hurricane Isaac: Gulf Coast Coal and Petrochemical Facilities still not Storm Ready.


Independent academics have used SkyTruth’s mountaintop removal (MTR) dataset to produce groundbreaking studies that have fundamentally changed the debate about the societal costs and benefits of MTR. We are especially gratified by the contribution our work has made in this arena.

In 2013, John co-authored a paper in the Journal BioScience titled “The overlooked terrestrial impacts of mountaintop mining.”

Among work by outside researchers, two studies in particular were cited by the Environmental Protection Agency (EPA) in their decision to overturn a permit that had been issued by the Army Corps of Engineers to expand the Spruce #1 mine in Logan County, WV. It is only the second time in EPA’s history that they have exercised this authority under the Clean Water Act.

The studies cited are:

How Many Mountains Can We Mine?” published in the journal Environmental Science and Technology. The research by Dr. Emily Bernhardt, a biologist at Duke University in Durham, North Carolina, provided the first conclusive evidence of a direct link between mountaintop removal mining to downstream water pollution and related environmental destruction.

The association between mountaintop mining and birth defects among live births in central Appalachia, 1996–2003” in the journal Environmental Science. Authors Melissa Ahern a health economist at Washington State University, Michael Hendryx an epidemiologist at West Virginia University, and their colleagues, found significantly higher birth defects in communities near MTR operations.

In addition, our MTR analysis has been used in many other studies including:

Michael Hendryx and Kestrel Innes-Wimsatt of West Virginia University published study in the Journal Ecophsycology titled “Increased Risk of Depression for People Living in Coal Mining Areas of Central Appalachia.”

Researchers at EPA, USGS, WVU and SkyTruth authored a study published in BioOne titled “The Overlooked Terrestrial Impacts of Mountaintop Mining,” which calculated cumulative loss of topographic complexity, forests, soil, carbon sequestration capacity, biodiversity, and human health due to MTR.

Nicholas Zegre and Andrew Miller at West Virginia University authored a paper aggregating existing knowledge on the hydrological implications of MTR mining and highlighting areas for future. The paper, titled “Mountaintop Removal Mining and Catchment Hydrology,” was published in the journal Water.

Researchers Nathaniel “Than” Hitt and Douglas Chambers from USGS conducted a study to determine the impact of MTR mining on fish populations and biodiversity downstream from mining sites at select watersheds in southern West Virginia. Their paper, “Temporal changes in taxonomic and functional diversity of fish assemblages downstream from mountaintop mining” was published in the journal Freshwater Science.


A paper in the December 2013 issue of the journal Endocrinology, used our tabulation and mapping of Colorado Oil and Gas Commission data on wells active as of June 2008. The paper by Christopher D. Kassotis of the Department of Obstetrics, Gynecology and Women’s Health and Division of Biological Sciences at the University of Missouri, and colleagues is titled “Estrogen and androgen receptor activities of hydraulic fracturing chemicals and surface and ground water in a drilling-dense region.”

Other recent works that have cited our fracking data or analysis include the following two books by CRC Press:

Hydraulic Fracturing Impacts and Technology published June 2015. Authored by Venki Uddameri, Professor and director of water resources Center at Texas Tech University and colleagues.

Wastewater and Shale Formation Development: Risks, Mitigation, and Regulation published June 24, 2015. Authored by Sheila Olmstead, associate professor of public affairs at the University of Texas at Austin.

In January 2016, our work on fracking and mountaintop removal was referenced multiple times in a chapter of the book Risk Analysis of Natural Hazards: Interdisciplinary Challenges and Integrated Solutions. Published by Springer, the book is the 19th volume in the series Risk, Governance and Society, begun in 1986 titled.


Photo of flooding aftermath in West Virginia

Come Hell & High Water: Flooding in West Virginia

In late June devastating flooding hit many communities across southern West Virginia resulting in over 20 fatalities and complete destruction of homes and businesses across the Mountain State. Because we are located in West Virginia and have been studying mountaintop removal (MTR) coal mining across Appalachia, we’ve received a number of questions about what role MTR mining may have played in this recent disaster.

Depending on the amount of mining in the impacted watersheds, the quality of existing baseline data, and the number of measurements taken during and after the flood, scientists may not find a “smoking gun” directly linking the severity of this flood event with MTR mining. But let us take a look at what we do know about the relationship between flooding and MTR mining.

Drainage Sketches


If you are familiar with stormwater runoff issues then you have probably seen a diagram like the one above. Soil and vegetation absorb water. Impervious surfaces, like rock and pavement, do not. Since blasting off ridge tops to reach seams of buried coal strips the mountains of soil and vegetation, it seems logical that MTR mining would contribute to more intense flash floods. But even after decades of study there are a surprising number of gaps in our understanding of exactly how mining alters flooding.

Photo of flooding aftermath around Clendenin, W.Va.

Debris and mud are strewn around Clendenin, W.Va., after flood waters receded. Photo by Sam Owens, courtesy Charleston Gazette-Mail.

Research conducted so far suggests that MTR mining can contribute to greater flooding during intense rainfall events, but some studies actually found less severe flooding in watersheds with mining. Several of these studies suggested that valley-fills and underground mine workings have the ability to retain water, which may account for less severe “peaks” during moderately severe storms. If you want to dig into the details, I recommend starting with the summary of hydrological studies on MTR contained in Table 1 of this paper by Dr. Nicholas Zegre and Andrew Miller from West Virginia University.

What most of these studies have in common is that the researchers must at least know where mining occurred and how much surface area was impacted by said mining. This is where our work here at SkyTruth comes into play because we’ve been mapping the when, where, and how much of MTR mining for over forty years.

Thanks to a satellite record going back to the 1970’s, SkyTruth can look back in time to measure the footprint of mining in Appalachia. We continue to make this data freely available for research, and so far our decade-by-decade analysis has been cited in at least six peer-reviewed studies on the environmental and public health impacts of MTR. These studies investigate everything from the increased risk of birth defects and depression to impacts on biodiversity and hydrology. But clearly there are still many unanswered questions left to research.

Finally, it is worth noting that much of the rainfall (left) was concentrated on Greenbrier County, a part of the state with relatively little MTR mining. Neighboring Nicholas County, however, does have some large mines so it may be possible for hydrologists to diagnose and measure the difference in flooding between mined and unmined watersheds which received equivalent rainfall. But that will take time to decipher and analyze.

In the meantime, SkyTruth and our partners at Appalachian Voices and Duke University are working this summer  to update and refine our data about the spread of MTR mining in Appalachia. The resulting data will allow more comprehensive and more accurate research on the effects of MTR mining. Our vision is for this research and resulting studies on the impacts of MTR to lead to better decision-making about flood hazards, future mine permits, and mine reclamation.

Scientists develop precise methods to identify and measure three very different types of fishing activity

Scientists develop precise methods to identify and measure three very different types of fishing activity

Scientists develop precise methods to identify and measure three very different types of fishing activity

On dry land, ecologists and conservationists can map our human footprints on the landscape. We can see deforestation, mountaintop removal, river damming and development, and it is relatively easy to recognize our impacts on an ecosystem and the plants and animals that live there.

In the ocean, our impacts are less tangible. Water covers more than 70 percent of the surface of the globe and its resources are exploited as vigorously as those on land. Yet our footprints are lost to the ripples and waves. The effects of our exploits lie beneath the surface in a three-dimensional, liquid “landscape” that remains out of sight and far from reach.

Satellite tracking technology and big-data processing are helping solve that problem by allowing us to see and record the tracks of ships on the ocean. This week, a new study released in the journal PLoS ONE brings finer resolution to our newly developing view of how humans are using the seas. Researchers from Dalhousie University in Halifax, Nova Scotia have developed distinct methods for identifying the activity of vessels fishing with three different types of gear.

Commercial fishing vessels regularly broadcast their positions to satellites via an Automatic Identification System (AIS). By plotting these signals on a map of the ocean we can recreate their tracks and identify movement or behavior consistent with fishing. Until now, remote sensing methods have provided only a broad or incomplete view of fishing behavior.

The broad view, which tries to capture all fishing activity without considering the type of gear being used, is somewhat like trying to quantify land-based farming for a given area without distinguishing between livestock, row-crops or orchard farming.

There has also been work to develop more fine-scale views that focus in on a specific type of fishing. Previous studies have looked at trawling, for instance. While this work is significant, it doesn’t allow for a comprehensive view of fishing activity. Again, to take an analogy from the land, analyzing wheat farms doesn’t allow us to make conclusions about land use relative to all farming.

This new work allows researchers to take a comprehensive look at how fishers use the oceans by combining fine-scale analyses of three of the most common types of fishing, trawling, longlining and purse seining. It also allows them to see the amount of time spent actually fishing as opposed to something else such as transiting or hanging at anchor.

“We’re very much aware of the differences of the gear types, and we’ve tailor made our algorithms for that so we can really tell what is happening out there,” says Kristina Boerder, one of our academic partners and an author on the paper. “Because all three algorithms were developed in one place to fit into the same framework, it is the first opportunity to run these analyses all together.”

According to Elizabeth Madin, researcher from Macquarie University in New South Wales Australia, this work helps to fill critical gaps in the scientific understanding of how and where fishing is occurring on the high seas. “It’s something that’s been notoriously difficult to quantify over large scales with any accuracy in the past,” she says. “Perhaps equally importantly, this study improves our ability to harness the full power of the vast dataset of fishing patterns globally that has emerged through the use of satellite AIS technology. Marine scientists and ocean resource managers will find this incredibly valuable.

To develop their tools, Kristina and her team analyzed satellite-based AIS tracks from 2011 to Oct 2015. They looked at characteristics such as speed, changes in direction, how a vessel moves, and how long it engages in certain types of movement. Some characteristics were more important than others in identifying each type of gear. So in order to automate the identification process, they had to take a different approach for each fishing method.

For trawlers, they applied a machine learning approach. They fed a computer thousands of examples of trawling vessel tracks (millions of individual AIS signals) and asked the computer to identify patterns among those tracks. Having established the set of rules to define trawler patterns, the computer could then apply those rules to unidentified tracks and pick out trawling behavior.

Purse seiner behavior is distinct in that vessels move very quickly in a circle around a school of fish to set the net, then move very slowly for a period of time, drifting as they haul up their nets. For these vessels, the researchers applied a filtering process by which, step-by-step, the computer eliminated behavior that did not fit with the behavior of pulling up the net. By re-evaluating after each filter, and applying the next level of elimination, the algorithm narrowed in on purse seine fishing events with 97 percent accuracy.

Longliners posed a slightly different challenge because speed was not as relevant to longlining as it was to the other two gear types. In this case, the researchers used a data mining technique and applied methodology from land-based ecologists who study animal movements. Other work has shown that human fishing activity resembles that of animals searching for and hunting prey. “If an animal spends a lot of time in one confined area,” Kristina says, “there has to be something of interest there—they could be sleeping, or foraging, or hiding.” Longliners offer the same clues by spending a lot of time traveling back and forth over the same territory as they set and retrieve their lines and hooks.

Kristina says the team fed AIS signals into their computer and asked the computer to mine the data and pull out tracks that met a certain set of expectations for what longliner fishing behavior over time and space looked like. Evaluating each vessel track, the computer took note when a vessel began to behave according to the expectations given. It then applied the next level of expectations, highlighting tracks that met those, and re-evaluated again. This is the first time an automated process has been developed to identify fishing activity of longliners.

The new Dalhousie algorithms can be a game changer for fisheries management and conservation, especially in combination with Global Fishing Watch’s list of individual fishing vessels, which helps identify the species of fish being harvested. Knowing where and when a given species is being taken from the ocean allows for a much better assessment of fisheries management on a global scale.

Researchers will be able to study more precisely how human activity overlaps with such things as migration patterns of tuna, nursery areas for sharks, or ecosystems surrounding marine protected areas. “It is a tailor-made approach that can be used to search and evaluate fishing effort for any fleet anywhere in the world,” says Kristina. “We hope that other researchers and ocean managers will use our tools to further their work. It opens the door to a whole host of research questions that couldn’t be asked before.”

Impact Story: Global Fishing Watch


Global Fishing Watch is the product of a technology partnership between SkyTruth, Oceana, and Google, designed to enable anyone to see and understand apparent fishing effort worldwide. This, in turn, will help reduce overfishing and illegal fishing and help restore the ocean to sustainability and abundance.

The story of Global Fishing Watch is really the story of a team coming together over the vision of what might be possible with satellite data on a global scale.

More than a decade after its founding, SkyTruth had become known as the small nonprofit with a big-picture view of the world. Environmental organizations had been coming to us for help solving challenging problems with remote sensing. We had become a trusted source for unbiased analysis and indisputable imagery that revealed what was once invisible. So when we were asked to turn our analysis to the issue of commercial fishing far out at sea, it was a natural fit.

In 2012, Pew Charitable Trust’s Global Ocean Legacy program was encouraging conservation in the rich and diverse waters of Easter Island Province, a remote territory of Chile located in the southeastern Pacific Ocean, about 2,500 west of the mainland. Hoping to demonstrate the need for protection and the feasibility of monitoring, they looked to us for a solution.

Satellite photographs of illegal fishing in the area would have easily made the point, but such photos don’t exist. Contrary to common belief, no one is actually taking high resolution, fine-scale images of the entire world at all times. So we had to come up with a new method of looking at fishing behavior far over the horizon.

Using low-resolution satellite radar images, we detected the presence of ships in the water based on the radar reflectivity of their metal hulls. Then we learned to work with radio signals broadcast via the Automatic Identification System (AIS) used by many ships to avoid collisions at sea. Combining the data, our analysis showed that fishing was occurring in the open ocean right up to the edge of Chile’s territorial waters. It also revealed that not all fishing vessels were broadcasting their presence with AIS. That was enough to demonstrate that Chilean waters could be vulnerable to unscrupulous fishing behavior, and the Chilean government subsequently stationed a long-range reconnaissance airplane on Easter Island to monitor activity in the area. With that project, we quickly realized the power of AIS data to identify and track fishing activity over the horizon and out of sight. And that’s where the vision began.