A map of a burned area obtined from remote sensing contains 120 pixels. The remote sensing image shows that the fire is isolated to 73 of the 120 pixels.
a) how many km^2 of forest does the image represent?
b) how many km^2 of the forest is burned?
c) how many km^2 of forest remained after the fires?
I know that 1 pixel = 900m^2 but I do not know how to solve these problems.
To solve these problems, we need to use the given information and convert the pixels into an area in square kilometers.
a) To find the total area represented by the image, we need to multiply the total number of pixels by the area represented by each pixel. Given that 1 pixel = 900m², we can convert it to square kilometers by dividing by 1,000,000 (since there are 1,000,000 square meters in a square kilometer). So, the area represented by each pixel is 900m² / 1,000,000 = 0.0009 km².
Total area represented by the image = Number of pixels * Area represented by each pixel
= 120 * 0.0009 km²
= 0.108 km²
Therefore, the map represents an area of 0.108 km².
b) To find the area burned, we need to multiply the number of burned pixels by the area represented by each pixel. Given that the fire is isolated to 73 out of the 120 pixels, we can calculate:
Area burned = Number of burned pixels * Area represented by each pixel
= 73 * 0.0009 km²
= 0.0657 km²
Therefore, the image represents approximately 0.0657 km² of burned forest.
c) To find the remaining area after the fires, we can subtract the area burned from the total area represented by the image:
Area remaining = Total area represented - Area burned
= 0.108 km² - 0.0657 km²
= 0.0423 km²
Therefore, approximately 0.0423 km² of the forest remained after the fires.