On Sunday this week, the Guardian reported that deforestation in the Brazilian portion of the Amazon rainforest spiked by 190 percent over the last couple of months. This ugly bit of news came via remote sensing techniques; satellites orbiting the earth are particularly useful tools for monitoring things like deforestation. In Brazil, new satellites may help count up illegal logging that had purposefully been kept below 25 hectares, a threshold below which the older versions couldn’t detect.

Tracking deforestation, though, isn’t all that satellites can do. It seems counterintuitive that a camera floating a few hundred miles above your head could, say, monitor monarch butterfly migrations, but it can. It’s a pretty amazing camera up there. A group of remote sensing experts published an essay in the journal Conservation Biology last week that codified a series of conservation-related questions that our satellite army may be best suited to answer.

Remote sensing of the environment can generally be traced to the launch of Landsat 1, in 1972. We are up to Landsat 8 now, launched in 2013; it took those images of Lake Mead’s catastrophically low water levels up above. So what can that and many other satellites tell us?

For starters, remote sensing can probably help with measures of species distribution and abundances, and even how they move. The satellite imagery of land cover, primary productivity (measured by the normalized difference vegetation index or NDVI, which we covered last week in relation to how green spaces make for better students), even chlorophyll concentration—if used cleverly, perhaps with newly deployed sensors such as LIDAR, these could tell us how a given species of animal is doing. For some endangered species, that would be an invaluable resource.

Ecosystem response to human activity is another area that satellites have something to offer. Remote sensing could help quantify nitrogen inputs to an ecosystem, for example, or even create maps of coral bleaching. Though it is a broad range of questions, climate change inputs and outputs are both candidates for satellite tracking as well; for example, the ICESat missions (and an interim long-range plane-based version) are tracking ice loss at the poles, clearly an important indicator of just how long we have before Miami is under water.

Or how about much more rapid response kinds of tools? “Some decisions, such as responses to wildfires, droughts, oil spills, and illegal resource extraction require information within hours or days,” the authors write. The Fire Information Resource Management System is just one such example, using near real-time data from MODIS, on the Aqua and Terra satellites, to help guide fire management decisions. Opening up other satellites to quicker reporting, they suggest, would further help rapid response to environmental crises.

There are many other possibilities. Monitoring changes in ecosystem services, evaluating whether previous conservation efforts are bearing fruit, how expansion of agriculture and aquaculture are changing the ecosystems around them, and so on. “We hope our presentation of questions will encourage the conservation community to increase its application of remote sensing,” the authors write. “To help facilitate conservation practitioner access to cutting edge solutions, we challenge the government, donor, NGO, and academic communities to use their collective financial and human capital more efficiently to solve the questions presented here.”

The eyes in the sky are watching, and when it comes to conservation and the environment, that seems like a pretty good thing. – Dave Levitan | October 21, 2014

Source: Rose RA, Byler D, Eastman JR, et al (2014). Ten ways remote sensing can contribute to conservation, Conservation Biology. DOI: 10.1111/cobi.12397

Image: USGS/NASA, Landsat 8