The free and open policy adopted by the
European Space Agency (ESA) and NASA and the U.S. Geological Survey (USGS) has driven exponential growth in users downloading Earth observation data. For example, USGS reportsmore than 68 million downloads of Landsat 8 data between December 2008 and September 2017. The European Union has embarked upon the Copernicus program, which has at the time of writing (March 2018) launched six of its Sentinel satellites — 1 (a&b), 2 (a&b), 3(a), and 5p — with more planned in 2018 and the following years. The Copernicus mission has at its core continuity of service, meaning that we can expect coverage until at least 2030.
Traditional commercial players including Digital Globe (acquired by MacDonald Dettwiler and Associates in late 2017) and Airbus have been launching significantly larger, and much higher resolution multispectral satellites for the past two decades. These state-of-the-art satellites deliver images with a spatial resolution of up to
31 cm. In 2014, the U.S. government relaxed its restrictions on image resolution, by allowing companies to sell data at higher spatial resolution.
A flood of data
Earth observation satellite instruments fall broadly into two categories: passive sensors and active
sensors. Passive sensors are by far the most common imagers; they measure the amount of electromagnetic energy reflected by the Earth’s surface or atmosphere; they are affected by cloud coverage. Active sensors — such as Sentinel 1, which is a C-band Synthetic Aperture Radar (SAR) satellite — send a pulse of energy to the surface and then record returns to the sensor.
With so many EO satellites in orbit today, we have far more data than users can look at with their eyes. Spaceborne imagery is a prime example of “big data” and has traditionally been processed locally on machines operated by specialists. However,
the cost of cloud storage and computing has fallen dramatically in recent years. This has initiated an explosion in the use of EO data by companies and a growth in startups innovating to deliver new insights about the world around us. Whether it is counting the number of cars in the parking lots of a big box store and relating it to that company’s share price, or monitoring corn to predict yields and, therefore, commodity prices, the volume of EO data and the ability to process it quickly is changing our world.
Earth observation for disaster relief
One of the main advantages of EO data is that it gives us an unbiased eye on our planet. It allows the regular monitoring of our ecosystem like never before. From detailed
mapping of global forest cover in order to quantify anthropogenic changes to shaping and informing international policy, these can all be guided and informed by EO data.
There are many programs currently in place for disaster response; we will highlight three below. During a crisis, access to data needs to be fast, of high quality and decidedly accessible to allow for information to flow to relief efforts in as close to real-time as possible. At present, it is not possible to have real-time satellite imagery, but near-real time is becoming increasingly achievable.
First up, the
International Charter Space and Major Disasters. Data is supplied by the Charter’s 15 member space organizations. Each member has committed resources to support the provisions of the Charter and thus is helping to mitigate the effects of disasters on human life and property. You can investigate their work and imagery through their web portal.
Copernicus Emergency Management Service. In 2016, this service was activated 41 times; by the end of 2017, it had been activated 82 times. It provides a reliable worldwide mapping resource as well as European flood and fire risk services.
Finally, almost a year ago DigitalGlobe launched the
Open Data Program. This program opens up the DigitalGlobe First Look product enabling responders to look at pre-and post-event imagery from its range of high-resolution sensors. Partners are invited to make requests through their protocol. Other commercial companies also have similar programs, such as Planet’s disaster data service. All these programs allow for accurate information to flow into locations that most need them; the speed of delivering this data is the most significant challenge.
Earth observation for sustainable development — pixels for people
Ending poverty is the number one UN Sustainable Development Goal (SDG). However, reliable data about wealth can be incredibly hard to find if it exists at all. Earth observation data is a consistent but relatively low-cost solution to this problem. In 2016, Stanford University reported on poverty mapping using very high resolution (VHR) satellite imagery and machine learning. Researchers used nighttime lighting as a proxy for economic growth, combined with VHR satellite data and surveying on the ground (you can read the abstract of their paper here). As we have previously noted with more sensors being launched, we are on the cusp of a data revolution that will provide significant spatial and temporal coverage, offering a fuller breadth of knowledge about our planet than has ever been available.
Earth observation data will provide critical input to addressing all these goals, from infrastructure mapping with
VHR data to understanding our climate through sensors like Sentinel 5P, which has been delivering unrivaled high-quality atmospheric composition, air pollution, and ozone layer monitoring data since the end of 2017. Earth observation is such a key component to addressing the 17 UN SDGs that ESA has outlined how satellite data can be used to address each one of them.
The following are some of the more significant ongoing initiatives to address the SDGs:
1. — Earth Observation for Sustainable Development, an ESA program with a focus on urban development, agriculture & rural development, and water resources management. These are the three domains on which the EO4SD World Bank and ESA are focused in 2015–2018.
2. — Group on Earth Observations, and the Sustainable Development Goals. — ‘ GEO Earth Observations in Service of the 2030 Agenda’
3. — The United Nations initiative on Global Geospatial Information Management, which sets the agenda for the development of global geospatial information and to promote its use to address key global challenges. UNGGIM
4. — Global Partnership for Sustainable Development Data, a global network bringing together governments, the private sector, and civil society organizations dedicated to using the data revolution to achieve the SDGs. GPSDD
Increasingly, the focus is on extracting value from satellite data by tying it into existing datasets or utilizing the Internet of Things through in-situ sensors or crowdsourced data. It is the imagery combined with other types of data and new technologies that allows us to drive solutions at scale.
2018 is shaping up to be another growth year for Earth observation
In 2018, Radiant.Earth will report regularly on the Earth observation industry, sharing with our readers news about satellite launches, new developments, new entrants to the market as well as established ones and carefully follow this multi-billion-dollar industry. Radiant.Earth is focused on using Earth imagery for positive global impact.
Landsat-8 satellite image shows that key reservoirs in South Africa’s Western Cape province have dropped to critical levels. Credit: NASA/USGS
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