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Landsat-based tool helps spot deforestation

4 Minutes Read

Deforestation is a global problem, more so in the developing and the underdeveloped world, thanks to ineffective laws and corrupt administrations in some parts of the world. But help is at hand. Now, when a new road appears in the dense forests of Peru, or a patch of forest is felled Malaysia, anyone with an Internet connection can be alerted of the loss.

A Landsat-based alert system, developed by the World Resources Institute as part of its Global Forest Watch network, gives near-weekly alerts for changes smaller in size than a football field. The tool uses imagery from Landsat 7 and 8 to monitor forests across the world every eight days. That revisit time, or data cadence, together with Landsat’s 30 meter spatial resolution, allows land managers to know when small incursions into forests are being made — in time to respond before further damage is done.

Download the Global Forest Watch interactive map here 

Global Forest Watch (GFW) — whose goal is to provide decision makers with timely information about global forests — teamed up with the University of Maryland’s Global Land Analysis and Discovery (GLAD) team and scientist Matt Hansen to develop this revolutionary tool. The three essential ingredients are freely available Landsat data distributed by the USGS, the Hansen-GLAD tree cover loss algorithms, and Big Data computing power like that of Google’s Earth Engine.

Global Forest Watch
Pink shows loss and blue shows gains.

All of this is wrapped up in GFW’s user-friendly mapping interface. When you open it, what automatically pops up is the global annual tree cover loss and gain. Pink shows loss and blue shows gains on the map.

Global Forest Watch
A user can draw in the map or upload a shape of the area he wants to analyze or subscribe to.

A user can zoom in on a particular area and monitor the chages or draw in the map or upload a shape of the area he wants to analyze or subscribe to. The time scale is 15 years from 2001 to 2015, and a click on the scale at the bottom of the map gives a user a visualization of how the map changed in that time. The interactive map gives data based on forest change, land cover, land use and conservation. The global map also has little flags, which takes a user to crowsourced stories of rampant deforestation in those areas.

Landsat-based tool help spot deforestation
There is no data for some countries but users can always add their own data.

One just has to click on the “Country Data” button on top right to get country-specific data. In some places, GFW, whose ultimate aim is to cover entire Earth, doesn’t have data. What is interesting is a user can always add his/her data by clicking on “submit data” and a fill up some basic details like the type of data, what is shows, date of content, geographic coverage and metadata. A GWF note says although the team will make every effort to add all data submitted via the form, in cases where a type or format of data is supported, GFW team will contact the user.

Global Forest Watch
One can find the GLAD alerts under the forest change data at 30×30 meter resolution.

What sets the GLAD alerts apart is that they are measured at the same resolution as annual data displayed on the map and are hence at higher resolution and higher frequency than any existing alert products. One can find the GLAD alerts under the forest change data. The resolution is at 30 × 30 meters and geographic coverages are Brazil and Peru in South America; Burundi, Cameroon, Central African Republic, Democratic Republic of the Congo, Equatorial Guinea, Gabon, Republic of the Congo, Rwanda and Uganda in Central Africa; Brunei, Indonesia, Malaysia, Papua New Guinea and Timor Leste in Southeast Asia; and Russia Far East. The tool aims to expand in near future to cover the humid tropics.

Global Forest Watch
GLAD alerts for Malaysia.

One can combine the country data for these regions with the GLAD alerts data to see what’s going on a particular place. The more the red alerts, more deforestation. One can even choose the time on the time scale on the bottom bar to measure immediate changes during a chosen period of time.

[ALSO READ: World Bank’s interactive map shows where deforestation is severe]

The handy tool makes the database accessible to authorities broader than just forest managers. As Frances Seymour, a senior fellow at the Center for Global Development, points out, “Government agencies, civil society watchdogs, and companies trying to get deforestation out of their commodity supply chains can all use these alerts to target their efforts and mobilize quick response.”

Official forest land use plans are lacking or not openly shared in many countries. And as lack of transparency continues to be a legitimate contention especially in developing and underdeveloped parts of the world, the GFW-GLAD forest alert system tracks forest exploitation, including the nascent stages — new access roads, selective tree removals — and puts tools in the hands of all levels of government, private industry, and locals so all interested stakeholders in land use development and conservation can have the same set of facts.

“We hope the alerts stimulate improved, consensus-based planning on how remaining high carbon stock, high biodiversity forests will be developed and protected,” Hansen says.