I found it difficult to find statistics of the rate of destruction of the rainforests since the numbers I have found seem to apply to forests all over the world and not exclusively to rainforests.
However I think that analysing the destruction of forests in general will give us a good idea of how much harm human activity is doing to the environment and the need to ensure that the trend is reversed.
I have decided to compare the statistics provided by different organisations (both governmental and non-governmental).
The Food and Agriculture Organisation of the United Nations (FAO) publishes information gathered from the Forest Resources Assessment in 2005 that states:
“Each year about 13 million hectares of the world’s forests are lost due to deforestation, but the rate of net forest loss is slowing down, thanks to new planting and natural expansion of existing forests.
From 1990 to 2000, the net forest loss was 8.9 million hectares per year.
From 2000 to 2005, the net forest loss was 7.3 million hectares per year – an area the size of Sierra Leone or Panama and equivalent to 200 km2 per day.
Primary forests are lost or modified at a rate of 6 million hectares per year through deforestation or selective logging.
Thirty-seven countries and territories lost 1 percent or more of their forest area each year between 2000 and 2005, while 20 countries gained more than 1 percent per year due to natural expansion of forests and afforestation.”
The next Forest Resources Assessment to be carried out by the FAO is due in 2010. Using satellite data from 1975, 1990, 2000 and 2005, forest cover will be surveyed across the planet in about 13 500 plots, providing a sampling intensity of 1 percent of the global land surface. This survey will generate unprecedented information on global forest change – deforestation, afforestation and natural forest expansion. It will provide insight into the land uses that are replacing forests. It will identify changes in biomes that transcend national boundaries. And it will improve understanding of the global contributions of forests to greenhouse gas emissions and reductions.
The Assessment will provide the international community with up-to-date information on questions such as how much forest there is; how well it is managed and how much is being lost.
WWF quotes the statistics from the Forest Resources Assessment of 2005 (13 million hectares lost each year).
Greenpeace states that an area the size of a football pitch disappears every two seconds but it is unclear how this is measured.
Since the size of a football pitch is 120m*90m approximately (according to the BBC) this means that:
10800 sq metres are lost every two seconds (*30 for m/minute)
324.000 sq metres every minute (*60 for m/hour)
19.440.000 sq metres every hour (*24 for m/day)
4.66.560.000 sq metres every day (*7 for m/week)
3.265.920.000 sq metres every week (*52 for m/year)
1.69.827.840.000 sq metres every year.
Dividing metres by 1.000 to get hectares, this means that 169.827.840 hectares are lost every year- compared with the FAO estimate of 7.3 million hectares per year.
(Please let me know if you spot a mistake in my calculations!)
Unless I have calculated this incorrectly it seems that the Greenpeace estimate is substantially higher than that of FAO although I do not know for what reason.
Even if FAO was to publish the more accurate figure, 7.3 million hectares is too large an area of forest destructed to ignore.