The capacity to observe and study our planet from space faces serious challenges during the coming years. A host of aging satellites, along with several mainstay platforms that recently have failed, plus insufficient funding for future programs, are converging to form the perfect storm for a world of inadequate Earth information—information upon which scientists and policymakers worldwide have leaned heavily for decades.
A Global Predicament
The recent losses of two perennial workhorse satellites, the amazing Landsat 5 and Europe’s Envisat, have sent shock waves throughout the user community. To be fair, there are a few bright spots. The Landsat Data Continuity Mission (LDCM) is approaching (see “Inside the Landsat Data Continuity Mission,” page 20), and Canada’s RADARSAT-2 satellite is filling some gaps for Envisat users (see “Living in a Post-Envisat World,” page 24).
But currently there’s no blueprint for an LDCM follow-on mission, and the European debt crisis has policymakers there wringing their hands about the future of the Global Monitoring for Environment and Security (GMES) program, which comprises a total of six Sentinel satellites, three of which are planned to begin operations next year.
Seven Billion Reasons to Care
The world’s natural resources are dwindling, and evidence provided by 40 years of Earth observation satellites identifies humans as the agents of change in most cases. Seven billion human inhabitants are placing unprecedented strain on global resources, particularly forests, water and food.
Every three seconds we lose a swath of forest the size of a football field. More than 80 percent of those living in rural Africa alone depend on forests and woodland for all energy needs. When humans rapidly consume forests for fuel or slash-and‑burn agriculture, Earth begins to lose its critical ability to capture carbon from the atmosphere, and the loss of biodiversity often leads to the extinction of untold plant and animal species. But everyone needs to eat, right?
“Feeding the people of the world requires not only land for agriculture, but it also requires fresh water and energy,” explains James Irons, Landsat project scientist at NASA’s Goddard Space Flight Center in Greenbelt, Md. “What we’ve done with satellites over the past 40 years is to revolutionize how we monitor agriculture, forests, fresh water consumption and other Earth resources required by the global population.”
About half of Earth’s seven billion people have been added during the 40 years Landsat has been in existence, and the United Nations expects a billion more will be added by 2025. Irons says the pressure of feeding everyone requires a tool with a whole-world view, making satellites an indispensable resource for scientists and policymakers alike.
Commercial Matters Too
Although firms like DigitalGlobe and GeoEye were created to serve primarily government customers, hundreds of scientists are finding incredible new ways to leverage high-resolution commercial data. In April 2012, DigitalGlobe announced it’s adding a shortwave infrared sensor to its WorldView-3 satellite, which would make the satellite’s data quite valuable for applications such as mineral exploration, vegetation moisture monitoring and water-resource management. But a recent round of defense budget cuts has cast doubt on the long-term future of both companies, neither of which could operate without a government-guaranteed stipend.
The Bottom Line
When Socrates urged us to “rise to the top of the atmosphere and beyond” to “fully understand the world,” little did anyone realize he was being quite literal with his sage counsel. Now we know. And even though it requires a bunch of rocket scientists to make it happen, it’s hardly rocket science to understand the importance of preserving our home planet. All it takes is horse sense.
— Jeff Specht, publisher, Earth Imaging Journal