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Can you see deforestation on Google Earth?
University of Maryland geographer Matthew Hansen has partnered with Google Earth to process satellite images of several forests over the past decade to help track deforestation. Less than half of that forest loss was gained during that period: only 309,000 square miles.
What is forest deforestation?
Deforestation refers to the decrease in forest areas across the world that are lost for other uses such as agricultural croplands, urbanization, or mining activities. Greatly accelerated by human activities since 1960, deforestation has been negatively affecting natural ecosystems, biodiversity, and the climate.
How have the rates of deforestation in the Amazon rainforest changed over time?
Deforestation of the Amazon rainforest in Brazil has surged to its highest level since 2008, the country’s space agency (Inpe) reports. A total of 11,088 sq km (4,281 sq miles) of rainforest were destroyed from August 2019 to July 2020. This is a 9.5% increase from the previous year.
What is the rate of global deforestation?
Between 2015 and 2020, the rate of deforestation was estimated at 10 million hectares per year, down from 16 million hectares per year in the 1990s. The area of primary forest worldwide has decreased by over 80 million hectares since 1990.
How to calculate forest cover in Google Earth?
You can adjust this by calculating the actual minimum areas you were using (see step 6 below). Currently, Google Earth Engine has several tree cover datasets in the catalogue, including the Global Forest Change (GFC) (year 2000) and GLCF: Landsat Tree Cover Continuous Fields (2000, 2005, and 2010). Here, we use the Global Forest Change dataset. 1.
How to calculate statistics in Google Earth Engine?
As you learned in the Earth Engine API tutorial, the key method for calculating statistics in an image region is reduceRegion (). ( Learn more about reducing image regions .) For example, suppose we want to calculate the number of pixels estimated to represent forest loss during the study period. For that purpose, consider the following code:
How to estimate the loss of a tree in Google Earth?
You can estimate the tree cover after the loss by subtracting the loss from the previous tree cover. You can also add tree gain if you have data. 1. Use the derived tree cover and tree loss from the previous steps. 2. Create a new tree cover by removing the tree loss. // Unmask the derived loss.
How do you calculate area in Earth Engine?
To help compute areas, Earth Engine has the ee.Image.pixelArea () method which generates an image in which the value of each pixel is the pixel’s area in square meters. Multiplying the loss image with this area image and then summing over the result gives us a measure of area: