A Web search of environmental organizations yielded a range of estimates of the amount of forest clearing that is occurring worldwide:

Estimate 1: 1 acre per second

Estimate 2: 80,000 acres per day

Estimate 3: 32,000 ha per day

Convert the first two estimates into hectares per year and compare them.

There are 2.47 acres per hectare (see “Do the Math: Converting Between Hectares and Acres”). Therefore, 1 acre = 0.40 ha.

Estimate 1: 1.0 acre/second × 0.40 ha /acre

= 0.40 ha/second 0.40 ha /second × 60 seconds/minute × 60 minutes/hour × 24 hours/day × 365 days/year

= 12,614,400 ha cleared per year

Estimate 2: 80,000 acres/day × 0.40 ha/acre = 32,000 ha cleared per day

Your Turn Notice that Estimate 2, when converted to hectares, is identical to Estimate 3. Now convert the estimate of 32,000 ha/day into the amount cleared per year. How much larger is Estimate 1 than Estimate 2? Why might environmental organizations, or anyone else, choose to present similar information in different ways?