In October 2008, scientists with the Royal Botanical Garden at Kew discovered a rich pocket of biodiversity, including several notable new species, in a remote highland forest in Mozambique. Trekking into the inaccessible, 17,000-acre region, botanists and biologists found 200 types of butterflies, hundreds of plant species, and numerous animals and insects, including three new species of Lepidoptera butterfly and a new member of the poisonous Gaboon viper family.
What’s significant about this find is that it was initiated not by some intrepid adventurer, but rather by a scientist sitting behind his computer. Three years prior, conservationist Julian Bayliss identified the site - Mount Mabu - using Google Earth. Bayliss, a Tanzanian ecologist, then helped plan and lead the expedition.
The use of Google Earth to make a virtual discovery, which then led to an actual one, is just the latest example of how the spread of satellite technology - and related computer applications such as Google Earth - are changing the way scientists, conservationists, and ordinary citizens are monitoring the environment and communicating their findings to the public.
Once the exclusive domain of the military, government officials, and specialised scientists, satellite technology is being democratised and is fast becoming an indispensable tool for researchers across a wide spectrum of environmental fields. In the past several years, one of the chief uses for satellite imagery has been to accurately quantify the loss of tropical forests from the Amazon, to the Congo, to Indonesia. In Brazil, scientists and state environmental protection officials can now monitor fires and forest clearing almost in real-time and take action to combat the deforestation.
But perhaps the most revolutionary advance in using satellites to monitor the planet has been the ever-widening use of remote sensing technology by ordinary citizens. Google Earth has been instrumental in this development and represents a critical point in its evolution, allowing anyone with an Internet connection to attach data to a geographic representation of Earth. Citizens and environmental groups are now using Google Earth to tracks threats to pristine rivers from hydroelectric projects, catalogue endangered species, help indigenous people in the Amazon protect their land, and alert citizens and government officials that boats are illegally fishing off the Canary Islands.
"A decade ago, high-resolution satellite imagery for the whole planet would have been accessible only to a handful of people working in government agencies, resource extraction, or as scientists,” said David Tryse, an Internet technology specialist - and ordinary citizen - who has developed numerous Google Earth applications now being used by scientists and conservation groups. “Today it is in the hands of millions of people. It's impossible to care about something if you don't know it exists, but now people can fly across the planet and zoom in to see for themselves the huge fires from Shell's gas-flaring operations in the Nigerian delta or follow the discoloured toxic runoff along a hundred kilometres of rain forest river downstream from a goldmine in Peru or Indonesian Papua."
The first launch of a non-weather satellite for civilian use occurred in 1972, when NASA put Landsat into orbit to monitor the planet’s landmasses, tracking everything from desertification to changes in agriculture. Since then, ever-more sophisticated satellites have used cameras and a variety of sensors - including passive microwave, which can penetrate clouds to image the earth’s surface, and infrared sensors that can measure temperatures - to monitor a host of physical processes. One of the key functions has been the use of passive microwave technology to chronicle the steady decline of Arctic sea ice over the past 30 years.
Today, many countries use satellites to monitor their environment, including Brazil, which has one of the world’s most sophisticated systems for tracking deforestation. Brazil uses two systems that can rapidly identify where forest loss is occurring, giving the country’s environmental protection agency the technical capacity - although not necessarily the political will - to combat deforestation as it happens. Those systems rely on optical sensors and thus cannot see through clouds, but Brazil will soon launch its own earth observation satellite with cloud-penetrating technology, known as LIDAR.
Greg Asner of the Carnegie Institution’s Department of Global Ecology at Stanford University has used advanced LIDAR technology to scan a Hawaiian forest and identify alien plant species by their canopies and the amount of ground plants that grow under them.
A new frontier for remote sensing is the emergence of REDD (Reducing Emissions from Deforestation and Degradation), a mechanism for compensating tropical countries for conserving their forests. To date, one of the biggest hurdles for the concept has been establishing credible national baselines for deforestation rates - in order to compensate countries for "avoided deforestation", officials must first know how much forest the country has been clearing on a historical basis. For the remote sensing community, REDD presents an opportunity to showcase the power of remote sensing and generate a source of funding for countries to improve their sensing capabilities.
Introduced in 2005, Google Earth - which can be downloaded for free - aggregates and organises satellite imagery, aerial photography, and three-D global information system data from a range of sources and presents it in a format that is easily accessible to the general public. Through KML, Google Earth's programming language, users “interact” with the planet, attaching images and other information to geospatial data. This makes Google Earth an ideal tool for conservationists, such as the group Save the Elephants, which tracks the movement of elephants across Africa to see where they come into conflict with humans and where they forage. To further such conservation goals, Google has developed its Outreach program, an initiative that works with nonprofits to develop tools using Google Earth.
Part of the inspiration for Google Earth Outreach came from within the company itself. Rebecca Moore, a programmer at Google, used Google Earth to document a planned logging project near her home in Santa Cruz County, Calif. Working with members from her community, Moore created a virtual map of the area that would be affected. Her subsequent data animation, which took users on a virtual flyover across the proposed logging zone, generated a firestorm of protest and led to the cancellation of the project. Google Outreach was established shortly thereafter, in June 2007, with Moore in charge.