Glossary

The Felled Tree Counter is a tool developed by MapBiomas. Using daily deforestation alerts from the National Institute for Spatial Research (INPE) DETER program, the Counter multiplies this data by the number of trees on each hectare within the Amazon Basin. The estimate is based on a broad study carried out by over a hundred scientists that was published in Science magazine in October, 2013. The study mapped out 16,000 different species in Amazonia and calculated an average of 565 trees per hectare of forest.

Because the DETER alerts are released on a weekly basis, the Counter can include a real-time estimate of how many trees are being cut down. It works like this: every Friday, INPE updates its data as compared to the previous week. (For example, the rate reported on January 13th will correspond to the period from December 30-January 5, not January 7-12.)

Based on this new INPE data—the most current available—the Counter also updates its deforestation rate on a weekly basis, at midday on Fridays, including the conversion of square kilometers to the number of trees. As the number applies to the previous week, the index is replicated for the current week so as to be constant and manage to produce a real-time estimate.

The Counter is part of the PlenaMata Rainforest Monitor, a project supported by MapBiomas, InfoAmazonia, Natura and Hacklab working to protect the rainforest and end deforestation in the Amazon. The monitor provides information on the nine states composing the Brazilian Legal Amazon and the municipalities within them, together with the Indigenous Territories and Conservation Units located in the region. The tool also calculates deforestation rate, the area of deforested land together with weekly, monthly and yearly evolution.