NASA Satellite Data and Analysis Can Make Earth Better
July 6th, 2020
Via Seed Daily, a look at how NASA satellite data and analysis can make the Earth better:
The number of illegal gold mines in the Amazon is increasing so fast that activists have turned to satellite imagery to identify them. Still, with thousands of new mines a year, the work was overwhelming scientists at Earthrise Alliance – they needed more hands on deck. That’s how ninth graders in Weston, Massachusetts, began locating illegal mining activity in Brazil’s protected Yanomami territory.
Earthrise is one of numerous organizations getting Earth-observation images, data, and analysis – much of which NASA makes available for free – into the hands of people working on sustainability projects. These efforts by many different aid groups are tracking illegal mining, deforestation, and groundwater resources and informing the decisions of small farmers and governments trying to support them in regions that are feeling the worst effects of climate change.
Earthrise was working with Survival International, a group that has been reporting on illegal mines in the Yanomami territory for years. Miners bring disease, like malaria and tuberculosis, which can devastate local tribes that have had little contact with people outside their communities, according to Survival International. The highly contagious novel coronavirus now also threatens the region. In addition, the mines themselves pollute the land and waterways with mercury and other toxic substances.
Earthrise illustrated a striking rise in the number of new mines in the area in a graphic for Survival International. A few months later, shortly before schools across the United States closed in early 2020 amid the global pandemic, Earthrise asked Weston High School freshmen to comb Earth-observation data for environmental stories.
Examining satellite imagery from NASA, the European Space Agency, and the company Maxar Technologies, the students identified previously unreported illegal mines. The program is part of the Earthrise Education initiative, which provides students with an internet-based tool to use satellite imagery to investigate real problems that are in the news.
Headquartered in Washington, D.C., the Earthrise Alliance was founded in 2019 by former NASA officials as a merging of several projects that were using space resources to improve environmental conditions on Earth. The organization’s chief technology officer, Dan Hammer, previously worked as a presidential innovation fellow with NASA’s chief technology officer for information technology, where he made NASA data more accessible to the public.
“We offer additional perspective, which was the idea of Earthrise in the first place,” said Hammer, referring to the Apollo 8 photo for which the organization is named. Taken during the first crewed mission into lunar orbit, the photo shows Earth rising over the Moon’s horizon, giving humanity a first glimpse of the home planet from another celestial body.
“That original image alone was able to shift perspective for a lot of people,” Hammer said. “We’re offering that perspective for emerging news events, the spaceship Earth perspective.”
Self-Reflection
NASA has been looking back at Earth since the agency was established. In 1960, the agency began sending satellites into orbit to capture Earth images to improve weather predictions and maps. In 1961, Alan Shepard caught a view of Earth as the first American in suborbital space with Project Mercury.
Astronauts in the Apollo program in the 1960s and ’70s received photography training, not only to learn how to use the equipment, like cameras bracket-mounted to their spacesuits, but also to develop an eye for science images. These efforts led to the Earthrise photo and other famous images, including the iconic Blue Marble shot.
Images from these early Mercury and Apollo missions were the inspiration for the Landsat Program, which in 1972 launched the first satellite tasked specifically with observing and collecting data on Earth’s landmasses. The program has been in continuous operation since then, in partnership with the U.S. Geological Survey, which currently operates Landsat 8.
Today NASA has a fleet of satellites gathering Earth data, in addition to ambitious airborne and ground-based observation campaigns. Other governments and private companies have billions of dollars’ worth of satellites looking back at Earth. NASA also has the resources to process this data and develop predictive models and analysis.
The agency makes its Earth data available for free to the public. In some cases, organizations are working directly with NASA, benefiting from the agency’s computing power, modeling, and analysis. Organizations can also access the rapidly increasing Earth-observation data from the space agency and other governments and companies around the world.
Striking Gold, Helping Farmers
The problem of illegal gold mines isn’t unique to Brazil. It’s a global phenomenon that gets worse when gold prices rise.
In Ghana, environmental officials used Landsat data and algorithms developed by NASA to identify hotspots of illegal mining activity and revoke licenses from scores of companies collecting gold while avoiding environmental oversight and taxes.
Davis Adieno, who oversees the collaboration from Nairobi, Kenya, where he is program director for the Global Partnership for Sustainable Development Data, said the project is also forward-looking.
“The Ghanaian government is using this data to communicate the impact of illegal mines, but also, more importantly, how areas that have already been impacted could be recovered,” he said.
Working with the Global Partnership and other partners, NASA’s Brian Killough produced the initial data cube platform for five African countries – Ghana, Kenya, Sierra Leone, Senegal, and Tanzania – tailoring it to specific projects and training initial users. The successful model has now been scaled up for Digital Earth Africa, which makes free Earth-observation data available and usable in an increasing number of countries across the continent.
Data cubes are stacks of satellite data configured to allow the use of powerful cloud computing and rapid analyses, Killough explained. Satellite data from many days or years can be organized into a cube, with dimensions of space (latitude and longitude) and time. These cubes are made of small pixels that hold data at a scale of 30-meters – about the size of a baseball diamond – which is Landsat’s resolution. Once in a cube, it is much easier to analyze and apply the data.
Killough and his team at NASA’s Langley Research Center in Hampton, Virginia, work directly with the users of the data resources they’ve created.
“We help them interpret the data and adjust the tools for their needs,” he said. “We also conduct training in each country, where we give people an understanding of the data and tools and let them use it on their own.”
Adieno said Killough “introduced what is possible – what type of data is available, the duration, what you can actually do with the infrastructure, with the algorithms that are available – which helped the countries identify who was best-placed to use it.”
In most cases, the satellite data tools are being used by people who have already been working with satellite imagery, but with less powerful capabilities and extremely cumbersome and often untenable downloading and processing times.
Adieno said officials in Senegal purchased private data for their project but then later moved to the data cube infrastructure for their analysis. “The results were more or less the same, which means they didn’t need to spend that money,” Davis said. “The value here is access to free, open source satellite data that’s analysis-ready.”
Killough agreed. “People in the developing countries we’ve been working with recognize that satellite data could have a huge impact,” he says. “But they have struggled with the preparation and the understanding of how to directly apply it to their applications. That’s where I think we’ve made great progress.”
The data resources are “certainly very efficient and effective,” said Victor Addabor, who heads Ghana’s National Disaster Management Organization.
Addabor worked with Killough to use Landsat data to identify the rate at which small farmers in the country’s north are adopting new growing techniques, like using drought-resistant seeds. This type of information helps the government determine the best ways to support small farmers in remote areas who are making decisions individually while also playing a major role in the country’s food security.
“That One Right Decision”
Indeed, unlike large agricultural producers in Europe and the United States, the vast majority of farmers around the world are working small plots of land, feeding much of Earth’s population without coordination. These farmers are disproportionately affected by decreasing water resources and rising temperatures
“In many places, if farmers don’t make that one right decision, it can mean the whole year is incredibly challenging for them. It can mean that the kids don’t go to school or families don’t have enough to eat,” said Eliot Levine, director of the Environment Technical Support Unit at Mercy Corps.
The Portland-based organization has been providing humanitarian relief around the world for decades and, more recently, is working with NASA on a partnership that uses satellite data to support science-informed policy and sometimes deliver information directly to people who need it.
Mercy Corps and NASA are collaborating in Kenya to reach farmers with a combination of precise weather and agronomic information. The work is part of Mercy Corps’ AgriFin program, which focuses on building the capacities of smallholder farmers, using cellphones and texting technology to deliver information about weather forecasts, seed types, financial products, market prices, and other relevant resources.
“Through our partnership with NASA, we are providing farmers with information and tools they have never had access to before,” Levine said.
“Should you plant now or wait? Water now or wait because rain is coming? Farmers need access to information,” Levine said. “We envision a future where every small-holder farmer prospers in a digitally interconnected world.”
The effort is part of a growing collaboration between NASA and Mercy Corps, a partnership that began in 2015 with an early project to map groundwater resources in Niger and was formalized in 2019 with a Space Act Agreement.
Shanna McClain, global partnerships manager at NASA Headquarters in Washington, said the agency was looking to “engage with partners that it hasn’t worked with in the past in the hope of achieving new ways of understanding complex human and environmental challenges.”
As the collaboration with Mercy Corps matured, McClain and Levine saw increasing possibilities for future work, as they had hoped they would.
“We didn’t just want to work with a new type of partner,” McClain said. “We wanted to see the magic that comes only from partnership.”
The formal agreement “essentially helps recognize our interest in doing this work as a shared endeavor,” she said, noting no money is changing hands. “We’re putting in an equal amount of funding and capacity.”
NASA scientists have worked with Mercy Corps from their desks and at the sites of international projects. The agency provides Earth science insights, in addition to data and analysis that Mercy Corps wouldn’t be able to produce on its own.
Together, NASA and Mercy Corps are helping to strengthen the resilience of communities around the world.
Earth Data for Earth
Earthrise estimates that more than half a trillion dollars has been spent on public and private satellites looking back at our own planet, primarily for military intelligence and profit-driven fields like commodity trading.
Earthrise, along with Digital Earth Africa and Mercy Corps, is repurposing this technology.
“There’s value that filters down when you’re fundamentally aware,” said Earthrise’s Hammer. “We’re leveraging the hundreds of billions of dollars of existing investment for Earth literacy.”
With Earth-observation data, people can assess how their own lands are changing and what they can do to alter the direction of the change.
“Satellite data can be complex,” NASA’s Killough noted. “Making the data accessible and useable gives the local users more power to control their future.
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Read More »Scientists Use An Internet of Animals To Track and Save Wildlife
June 12th, 2020
Via The New York Times, an interesting report on how – through the use of tiny sensors and equipment aboard the space station – a project called ICARUS seeks to revolutionize animal tracking:
The International Space Station, orbiting some 240 miles above the planet, is about to join the effort to monitor the world’s wildlife — and to revolutionize the science of animal tracking.
A large antenna and other equipment aboard the orbiting outpost, installed by spacewalking Russian astronauts in 2018, are being tested and will become fully operational this summer. The system will relay a much wider range of data than previous tracking technologies, logging not just an animal’s location but also its physiology and environment. This will assist scientists, conservationists and others whose work requires close monitoring of wildlife on the move, and provide much more detailed information on the health of the world’s ecosystems.
The new approach, known as ICARUS — short for International Cooperation for Animal Research Using Space — will also be able to track animals across far larger areas than other technologies. At the same time, ICARUS has shrunk the size of the transmitters that the animals wear and made them far cheaper to boot.
These changes will allow researchers to track flocks of birds as they migrate over long distances, for instance, instead of monitoring only one or two birds at a time, as well as far smaller creatures, including insects. And, as climate change and habitat destruction roil the planet, ICARUS will allow biologists and wildlife managers to quickly respond to changes in where and when species migrate.
“It’s a new era of discovery,” said Walter Jetz, a professor of ecology and evolutionary biology at Yale, whose center is working with the project. “We will discover new migration paths, habitat requirements, things about species behavior that we didn’t even think about. That discovery will bring about all sorts of new questions.”
As an added bonus, people all over the world will one day be able to log on with a smartphone app to what’s known as the internet of animals to follow their favorite bird or tortoise or fish as it migrates and is tracked by the space station practically in real time.
The science of wildlife tracking, known as bio-logging, has come a long way in recent years. In the 1990s, researchers were still tracking large mammals using devices the size of lantern batteries. The technology has grown smaller since then, but many collars and tags are still too big for some three-quarters of the world’s wild creatures.
This space-based approach to uncovering the hidden lives of animals is led by Martin Wikelski, the director of migration research at the Max Planck Institute for Animal Behavior in Germany, who pursued it with a passion for years to overcome gaps and drawbacks in current technologies. It has been funded primarily by DLR, the German space agency.
ICARUS combines off-the-shelf technology, which includes solar and GPS units, and new communication technology that was developed for this mission, and specifically designed for tracking small animals.
On the ground, researchers will attach solar-powered bio-loggers that are far smaller than other technology — the size of two fingernails. They weigh less than three grams, about one-tenth of an ounce, and technicians say they will soon have one gram trackers.
Once secured — an easy process that seldom harms the animal — the sensors will hitch a ride on an array of animals and insects, like locusts, songbirds and baby tortoises. Most current wildlife tracking technologies can’t be attached to creatures that weigh less than 100 grams, or about three and a half ounces. And while the new sensors are smaller and lighter, their advanced design will allow them to collect far more data by monitoring an animal’s physiology, including skin temperature and body position, and external conditions like weather metrics.
The technology can also be used to accomplish a range of goals beyond wildlife studies.
Dr. Wikelski has studied the ability of cows, domestic goats and sheep in Italy to sense earthquakes and volcanic eruptions hours before they happen. Behavioral changes can be picked up by the sensors, he said, so herd behavior may provide an early warning.
“We think something smells wrong to them and there is static in the air,” he said. “So they move into wooded areas where they have shelter.”
Why the animals react is not yet known.
Icarus could also help track elephants vulnerable to poaching in Africa, or keep tabs on species of bats, pangolins and other animals that have played a role in viral epidemics.
“With skin temperature we can see in the ducks in China whether the next avian influenza is starting,” Dr. Wikelski said.
The power of this new approach is partially based on the fact that the space station can pick up the signals of these animals almost anywhere on the planet (the station does not pass over Earth’s polar regions, however). And while other conservation projects have tracked sharks, birds and other migratory species with satellites, this one aims to be useful for a wide range of species that researchers can ask to have added.
The sensors it relies on, at about $500 each, are a fraction of the price of other widely used tags.
They can last an animal’s lifetime and even be reused. They are able to store up to 500 megabytes, an entire lifetime of data on an animal. A researcher need not retrieve the tag; its data can be downloaded with a computer or a smartphone.
ICARUS “will truly change the study of animal migration,” said Nathan Senner, a biologist at the University of South Carolina. He plans to use it for a study tracking the Hudsonian godwit, a shorebird that makes one of the world’s longest migrations, from southern Chile to Alaska.
“We could get location estimates that are much more precise and help us develop targeted on the ground conservation measures,” Dr. Senner said.
In Europe, studies show some 30 percent of migratory songbirds, or about 420 million, have disappeared. ICARUS may give a much more detailed answer to where and why the animals are dying and guide conservation measures.
Dr. Wikelski said he was asked by a farmer in the German village where he grew up why there were no swallows this year.
“It’s hard to say,” Dr. Wikelski said. “Did they die on the way south? Were they eaten in the Mediterranean? Were they hunted in North Africa? Were they poisoned in the Sahel? Was the weather really bad? Those are the kinds of things we will find out.”
ICARUS will provide data on an individual bird, as well as a collective. In a study by Dr. Wikelski and others at Max Planck Institute, researchers are tagging 1,200 blackbirds in the hopes of better understanding the timing and route of their travels and where and why their numbers are declining.
In the Galápagos Islands, sensors will be used on baby tortoises to track their migration, a project of the Galápagos Tortoise Movement Ecology Programme.
“No one knows how the hatchlings survive,” said Dr. Wikelski, who works with the program. “Those are the lost years of the sea turtles. Knowing where they go will allow us to protect them better.”
Because ICARUS has the capability of tagging many more animals than other technologies do, Dr. Wikelski likened it to a smartphone traffic app that can track many cars on a highway at once. One phone can provide a lot of information about one car, but many phones sending information to one app can offer information about traffic patterns.
One of the goals of the project, Dr. Wikelski said, is to help conservation managers respond to a changing world. Protected areas like wildlife parks and forest preserves are defined by fixed boundaries. But many species are on the move as climate and other changes cause shifts, and protecting them will require an understanding of where they are going and where new protected areas and corridors may need to be created.
The system will be open to researchers around the world to use for research. And the data, with some exceptions, will be accessible to everyone. Dr. Wikelski said readings from ICARUS could be combined with other kinds of information, such as the eBird database, to make the data even more robust.
Another ambition of ICARUS is to allow anyone with a smartphone to follow tagged migrating animals. One app, called Animal Tracker, already exists as a way to tap into ground-based wildlife tracking systems.
Dr. Wikelski hopes that connecting people to a single charismatic animal whose movements they can follow will build support for conservation. “If people hear Cecil the lion died it’s very real to them,” he said, referring to a lion in Zimbabwe that was killed by an American hunter in 2015. “But if you say 3,000 lions died nobody cares.”
Mark Hebblewhite, a wildlife biologist at the University of Montana who has used wildlife tracking technology for decades, said ICARUS would have the capacity to fill in many gaps in our knowledge of the natural world.
“We’ll get a lot of things from ICARUS we can’t get any other way,” he said. “It’s exciting.”
But technology has downsides as well, he said. Birds may suddenly and unpredictably change their migration, for example, after years of traveling the same way, and Dr. Hebblewhite said there was a danger that conservation decisions could be made by people “who don’t know anything about birds except dots on a map.”
Some might say nature should maintain a degree of mystery from an all-seeing eye in the sky, but Dr. Wikelski, not surprisingly, doesn’t agree.
“These animals are providing really important information, maybe for survival of humankind,” he said. “We should have this information.”
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Read More »New Satellite-Based Algorithm Pinpoints Crop Water Use
March 21st, 2020
Via Eurasia View, a report on a new satellite-based algorithm which can pinpoint crop water use:
The growing threat of drought and rising water demand have made accurate forecasts of crop water use critical for farmland water management and sustainability. But limitations in existing models and satellite data pose challenges for precise estimates of evapotranspiration — a combination of evaporation from soil and transpiration from plants. The process is complex and difficult to model, and existing remote-sensing data can’t provide accurate, high-resolution information on a daily basis.
A new high-resolution mapping framework called BESS-STAIR promises to do just that, around the globe. BESS-STAIR is composed of a satellite-driven biophysical model integrating plants’ water, carbon and energy cycles — the Breathing Earth System Simulator (BESS) — with a generic and fully automated fusion algorithm called STAIR (SaTellite dAta IntegRation).
The framework, developed by researchers with the U.S. Department of Energy’s Center for Advanced Bioenergy and Bioproducts Innovation (CABBI) at the University of Illinois at Urbana-Champaign, was tested in 12 sites across the U.S. Corn Belt, and its estimates have achieved the highest performance reported in any academic study so far.
The study, published in the European Geosciences Union’s Hydrology and Earth System Sciences journal, was led by CABBI’s Postdoctoral Research Associate Chongya Jiang and project lead Kaiyu Guan, Assistant Professor in the Department of Natural Resources and Environmental Sciences (NRES) and a Blue Waters Professor at the National Center for Supercomputing Applications (NCSA).
“BESS-STAIR has great potential to be a reliable tool for water resources management and precision agriculture applications for the U.S. Corn Belt and even worldwide, given the global coverage of its input data,” Jiang said.
Traditional remote-sensing methods for estimating evapotranspiration rely heavily on thermal radiation data, which measure the temperature of the plant canopy and soil as they cool through evaporation. But those methods have two drawbacks: the satellites can’t collect data on surface temperatures on cloudy days; and the temperature data aren’t very accurate, which in turn affects the accuracy of the evapotranspiration estimates, Jiang said.
The CABBI team instead focused on the plant’s carbon-water-energy cycles. Plants transpire water into the atmosphere through holes on their leaves called stomata. As the water goes out, carbon dioxide comes in, allowing the plant to conduct photosynthesis and form biomass.
The BESS-STAIR model first estimates photosynthesis, then the amount of carbon and water going in and out. Previous remote-sensing methods did not consider the carbon component as a constraint, Jiang said. “That’s the advance of this model.”
Another advantage: Surface temperature-based methods can only collect data under clear skies, so they have to interpolate evapotranspiration for cloudy days, creating gaps in the data, according to Jiang. The all-weather BESS-STAIR model uses surface reflectance, which is similar on clear and cloudy days, eliminating any gaps.
The STAIR algorithm fused data from two complementary satellite systems — Landsat and MODIS — to provide high-resolution data on a daily basis, providing both high spatial and high temporal resolution. Landsat collects detailed information about Earth’s land every eight to 16 days; MODIS provides a complete picture of the globe every day to capture more rapid land surface changes.
This isn’t the first time researchers have combined data from the two satellite sensors, but previous methods only worked in a small region over a short time period, Guan said. The previous algorithms were difficult to scale up and weren’t fully automatic, requiring significant human input, and they couldn’t be applied across broad areas over a longer time period.
By contrast, the CABBI team’s framework was evaluated in different regions across the U.S. Corn Belt over two decades, Jiang said. Researchers built a pipeline on NCSA’s supercomputer to automatically estimate surface reflectance as well as evapotranspiration on a large scale for extended time periods. Using data from 2000 to 2017, the team applied BESS-STAIR in 12 sites across the Corn Belt, comprehensively validating its evapotranspiration estimates with flux tower measurements at each site. They measured overall accuracy as well as spatial, seasonal, and interannual variations.
“We are able to provide daily, 30m-resolution evapotranspiration anytime and anywhere in the U.S. Corn Belt in hours, which is unprecedented,” Guan said.
The breakthrough will have real-time, practical benefits for U.S. farmers coping with the increasing severity of droughts, as documented in a number of recent studies.
“Precision agriculture is one of our major targets. Evapotranspiration is very important for irrigation and also very important to water management,” Guan said. “This is a solution that goes beyond experimental plots and impacts the real world, for millions of fields everywhere.”
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Read More »Satellite and Reanalysis Data Substitute Field Observations Over Asian Water Tower
November 14th, 2019
Via Space Daily, a look at how satellite and reanalysis data can impact research on Asia’s water tower:
The Tibetan Plateau (TP), known as the “Asian water tower” because of its huge storage of glacier, has a profound impact on local and downstream ecosystems. However, it is a challenge to establish and maintain in situ observations there due to the complex terrain. Scientists have found substitutes, thanks to satellite technology.
“Both satellite and reanalysis data sets are reliable to be substitutes to reproduce the water vapor features over TP, but the time scale should be considered.” said Yin Zhao, a doctoral student from the Institute of Atmospheric Physics, Chinese Academy of Sciences. Zhao is the lead author of a recently published study in Climate Dynamics, along with her mentor Prof. Tianjun Zhou.
In sharp contrast with the importance of the giant water tower, sufficient in situ observations in the TP have been lacking due to the complex terrain. So satellite and reanalysis data sets become substitutes.
“In recent years, new versions of satellite data have been released and more reanalysis data sets have been updated. However, their quality needs to be evaluated, in particular, the reliability of existing satellite and reanalysis data products in capturing features of water vapor over TP”, said Zhao.
After evaluating two NASA satellite data sets and seven widely used reanalysis data sets, they found both satellite data sets are reliable to reproduce the total column water vapor characteristics over TP and the difference between them is negligible, but the quality of reanalysis data sets varies with time scales considered.
“There is larger uncertainty among reanalysis data sets than that in satellite data sets because of the climate models, observations assimilated, and the assimilation process. So the quality of reanalysis data varies with the time scale considered and there is no perfect reanalysis data set”, Prof. Zhou suggested using reanalysis data with caution.
The team therefore constructed a skill weighted ensemble mean of reanalysis data sets. Taken the spatially gridded data AIRS-only as reference, the lager weights are given to the higher quality reanalysis data set. This quality weighted ensemble data performs better than unweighted ensemble data and most of the single reanalysis data.
“Our analysis provides essential information about both the strengths and weakness of the current existing substitutes for the observational data, including the satellite products and reanalysis data. We recommend the application of the skill weighted ensemble mean of reanalysis data in future studies of water cycle over the TP, as it takes different time scale into account”, said Zhao.
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Read More »Sharing Data For Improved Forest Protection And Monitoring
October 11th, 2019
Via Terra Daily, a look at the potential that sharing data has or improved forest protection and monitoring:
Although the mapping of aboveground biomass is now possible with satellite remote sensing, these maps still have to be calibrated and validated using on-site data gathered by researchers across the world. IIASA contributed to the establishment of a new global database to support Earth Observation and encourage investment in relevant field-based measurements and research.
Forest biomass is an essential indicator for monitoring the Earth’s ecosystems and climate. It also provides critical input to greenhouse gas accounting, estimation of carbon losses and forest degradation, assessment of renewable energy potential, and for developing climate change mitigation policies.
Although satellite remote sensing technology now allows researchers to produce extensive maps of aboveground biomass, these maps still require reliable, up-to-date, on-site data for calibration and validation.
Collecting data in the field by measuring trees and documenting species is, however, a very labor intensive, expensive, and time-consuming exercise and it would therefore make sense to bring together the many extant data sets to provide real added value for a number of applications. In terms of policy applications, doing so can also lead to improved biomass products and better monitoring of forest resources, which could in turn lead to more effective forest protection measures.
In a new paper published in the journal Scientific Data, 143 researchers involved in this type of data collection in the field, explored whether it was possible to build a network that openly shares their data on biomass for the benefit of different communities.
They particularly wanted to see if they could bring together as much on-site data on biomass as possible to prepare for new satellite missions, such as the European Space Agency’s BIOMASS mission, with a view to improving the accuracy of current remote sensing based products, and developing new synergies between remote sensing and ground-based ecosystem research communities.
Their efforts have resulted in the establishment of the Forest Observation System (FOS) – an international, collaborative initiative that aims to establish a global on-site forest aboveground biomass database to support Earth Observation and to encourage investment in relevant field-based measurements and research.
“Keeping in mind that this paper is a data descriptor and not a conventional paper with hypotheses, the whole idea behind this study is a new open database on biomass data. This is important for the following reasons: First, it represents a way to link the ecological/forestry and remote sensing communities.
It also overcomes existing data sharing barriers, while promoting data sharing beyond small, siloed communities. Lastly, it provides recognition to the people working in the field, including those who collect the data, which is why there are 143 coauthors on this paper, as they are all contributors to the database,” explains study lead author Dmitry Shchepashchenko, a researcher in the IIASA Ecosystems Services and Management Program.
The researchers collected data from 1,645 permanent forest sample plots from 274 locations distributed around the globe. This data has now been made available for download via the FOS website. The initiative represents the first attempt at bringing this type of data together from different networks in a single location.
The researchers point out that their work in this regard is ongoing and there are plans to continue adding more data sets and networks to the FOS. In addition to promoting data sharing, the system also promotes a new leading network on biomass data (through the FOS), which IIASA is leading and will continue to grow into the future.
Apart from the obvious benefits that data sharing hold for the scientific community, the data are also essential for training various models at IIASA such as the BioGeoChemistry Management Model (BGC-MAN) and the Global Forest Model (G4M). Several on-going IIASA projects, as well as other ecological-, biophysical-, and economic models and projects outside of IIASA will also benefit, which means that providing access to the data can improve models and understanding of biomass more generally.
“A great deal of effort has gone into collecting forest data in the past, but people working in the field (ecologists and forestry scientists) hardly ever share the collected data, or if they do, they share it only within ecological networks. The data are valuable not only for ecology, but also for remote sensing calibration and validation, in other words, to train algorithms that create biomass maps, and for assessing the accuracy of the products along with inputs to a variety of models. This piece of work represents a real step forward in sharing a very valuable biomass data set,” concludes IIASA researcher Linda See, who was also a study coauthor.
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Read More »Forecasting Agricultural Vulnerabilities On A Changing Planet
October 8th, 2019
Via Harvard Business School, an interesting article on the use of satellites to map the most at-risk agricultural zones to devise plans for safeguarding crops:
Around the world, farmers are wrestling with floods, droughts, and heat waves — environmental challenges to agriculture that are made both more severe and more frequent by climate change. In the US, this year’s record flooding in the Midwest and Great Plains caused over $3 billion in damage and left many farmers unable to plant, and vulnerable to subsequent heat waves. Rates of warming in Kenya already exceed the 1.5° threshold targeted by the Paris Agreement, with dire consequences for livestock and other forms of agriculture.
Imagine if we could predict how climate change will transform agriculture in the coming years, evaluating which crops are most vulnerable, and where. By identifying agricultural “hotspots” most exposed to climate change, we could begin to design adaptation strategies, including introducing more resilient crop species and, where possible, moving current crop cultivation to more accommodating ecologies. To do so, we would need a rigorous understanding of how environmental conditions affect crop yield, as well as detailed forecasts of how temperature and rainfall are likely to change in the years to come as climate change becomes more pronounced.
Building an accurate, working map of agricultural vulnerabilities due to climate change is the goal of Angela Rigden, a hydrologist and Rockefeller Foundation Planetary Health Postdoctoral Fellow at the Harvard University Center for the Environment. The first step in building such a map is improving current crop forecast models, which have traditionally used rainfall and temperature data to estimate “water stress” and “heat stress.” But, Rigden says, these are poor proxies for actual crop physiology. Just as sweating cools down our skin on a hot day, plants evaporate water from pores on their leaves in a process called “transpiration.” The amount of water lost to transpiration depends on the amount of water available in the root zone and the dryness of the air. Transpiration is often a good indicator of yield — the more a plant transpires, the more it yields.Until recently, measuring soil moisture was difficult, so previous studies used rainfall as a proxy for root-zone soil moisture. But rainfall is not a great proxy for soil moisture because different conditions lead to big differences in rainfall runoff, drainage, and evaporation.
Earlier this spring at the Harvard Global Health Institute, Rigden described how she set out to build a better forecasting model. Rigden turned to a new source of data — a satellite launched by NASA in 2015 called SMAP (Soil Moisture Active Passive). SMAP measures the amount of water in the top two inches of soil everywhere on the Earth’s surface every three days, generating data on root-zone soil moisture that is free and publicly available. SMAP data allowed Rigden to build a significantly improved predictive model of corn yields by climatic conditions in the midwestern US.
Rigden then set out to complete a similar study in Africa, where agriculture is much more vulnerable to drought and other climatic influences. To do so, Rigden needed data on African agricultural yields, but the publicly available data on agricultural output was primarily at the country level — not fine-grained enough to assess the impact of local climate conditions. Instead, Rigden used data from a second, European satellite-based instrument known as GOME-2 (Global Ozone Monitoring Experiment-2) that could detect fluorescence associated with photosynthesis. Rigden and her coauthors demonstrated that this fluorescence is a remarkably effective proxy for crop yield that allowed Rigden to describe the likely impact of varying climate conditions.
Mapping her model of crop yields against forecasts of climate change, Rigden is able to show that, although cultivation of corn in the midwestern US is relatively secure under most climate scenarios due to adequate availability of moisture, tea cultivation in Kenya is much more vulnerable, facing a decline of around 11% — a significant challenge, given the significance of tea in Kenya’s economy, which exports over $1 billion dollars annually. Rigden’s research suggests that this decline might be mitigated by, for example, planting drought-resistant tea cultivars and moving tea cultivation to higher altitudes. Such changes involve a long-term commitment, though, because tea plants require at least three years of maturation before harvest and have an economic lifespan of 50-60 years.
Climate change poses a grave threat to food security and global health. Ensuring that we can continue to feed the world’s growing population despite climate change will require effective adaptation measures by both governments and private agribusiness — what the United Nations’ Food and Agriculture Organization calls “Climate-Smart Agriculture.” Rigden’s case studies of Kenya and the American Midwest represent first steps in making our forecasts of the impacts of climate change on agriculture in different parts of the world accurate enough to guide adaptation strategies to safeguard the world’s ability to feed itself.
Anglea Rigden is currently performing a third case study in Madagascar. Collaborating with researchers in Harvard’s School of Public Health, she aims to utilize the crop predictions in conjunction with expert knowledge of local social, political, and economic events to predict and alleviate food insecurity in this region.
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