AFP - Getty Images
Images from outer space highlight the fragility — and the resilience — of our beautiful blue planet.
Technological advances aren't always kind to Mother Earth — witness the impact of nuclear waste, industrial emissions and plastic bottles — but high-tech environmental monitoring systems are also helping us get a handle on the state of our planet. It's good to remember that as Earth Week draws to a close.
Just in the past couple of years, NASA has added to the nation's fleet of Earth-observing satellites. In 2011, the $1.5 billion Suomi NPP satellite went into orbit, blazing a trail for a new generation of planet-watchers that can provide data about extreme weather as well as environmental indicators. Suomi's five sensor systems are tracking atmospheric and sea surface temperatures, biological productivity, ozone levels and much, much more.
This February, the $855 million Landsat Data Continuity Mission finally got off the ground, opening a new chapter for the 41-year-old Landsat Earth-monitoring program. LDCM will monitor surface temperatures around the planet and generate 400 images a day in visible and infrared wavelengths. Multi-wavelength observation is a key technology for monitoring the planet's health, because thermal infrared readings can tell you how vegetation is faring, how much heat the world's cities are putting out, and how the world is coping with climate change.
"If you want to deal with climate, you need observations, instead of just talking about belief or simulations," Compton Tucker, senior biospheric scientist at NASA's Goddard Space Flight Center, told NBC News.
Even Earth's gravity field can provide insights into how the planet is changing: Readings from the Gravity Recovery and Climate Experiment, or GRACE, have traced the loss of ice from the world's glaciers and ice caps by measuring subtle changes in our planet's distribution of mass. "It's really a phenomenal source of information to study water on the surface," Tucker said.
For decades, observations from outer space — including data from NASA satellites such as Terra and Aqua, as well as the National Oceanic and Atmospheric Administration's weather satellites and the Landsat constellation — have been helping scientists understand what's happening to our environment.
Suomi NPP and LDCM are continuing that legacy, but there are still concerns about the future: Last year, the National Research Council voiced grave concerns about America's aging Earth-observing system, saying that the projected loss of satellite capability "will have profound consequences on science and society, from weather forecasting to responding to natural hazards."
The federal government's money troubles could trigger more immediate cutbacks in the nation's Earth-watching capability. It may well turn out that the biggest obstacles to understanding what ails our planet aren't natural phenomena, but problems of our own making.
More about high-tech environmental monitoring:
- How's Earth's health? New network to keep tabs
- Landsat celebrates 40 years of watching our planet
- How satellites are saving the world
Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.