"The result showed that about 20 percent of the world's land area is currently wilderness or about 11.6 million square miles.Given that airplanes fly over just about every part of the world and that pollution travels by air and sea to every part of the world, I'd guess there isn't really any wilderness left, but here's the study's definition:
Most of that wilderness is in Australia, North America, North Asia and North Africa.
Comparing the old map to the new one showed that an estimated 1.3 million square miles — almost 10 percent of the wilderness area — have been lost in the past two decades.
The amount lost is equal to twice the land mass of Alaska, or about half the entire Amazon.
The study did not delve into reasons why, but Watson said it comes down to increased development by the planet's growing human population."
"For the study, researchers defined 'wilderness' as 'biologically and ecologically intact landscapes free of any significant human disturbance.'"
Let's put this in context.
|WILDERNESS LEFT||TOTAL SQUARE MILES/km2/acres||% OF TOTAL LAND|
|in the world||11.6 million sq mi / 7.4 billion acres||20%|
|in the USA||170.5K sq mi / 109,129,657 acres||5%|
|in Lower 48||82.1 K sq mi / 52,553,809 acres||2.7%|
|in Alaska||88.4K sq mi/ 56,575,848 acres||13.3%|
|Alaska total size||663,268 sq mi / 424,491,520 acres||100%|
|Wilderness size from NWPS ; Alaska total size from Wikipedia|
Wilderness disappears as people make short term decisions; about survival for some, about profit for many. Long term collective decisions, like the creation of the National Park Service by Teddy Roosevelt and the idea of setting aside natural areas for conservation, are what keep the small amount of wilderness we have left in the world.
As Alaskans debate where they can drill for oil, log for timber, mine for coal and gold and other minerals, I'd suggest some longer term thinking. Thinking that recognizes that what is rare is valuable. Wilderness is becoming rarer and rarer. Alaska's wilderness will become more and more valuable in the future. Rather than destroy it for meager short term profit, let's save it for longer term, more valuable benefit.
I haven't addressed why we need wilderness. I've written about before is described by Edward O. Wilson who talks about how the trillions of dollars worth of ecosystem services provided by nature - recycling and purifying water, cleaning the air, enriching the soil, etc.
For those who doubt the need, here are a few more resources.
National Geographic: What is Wilderness, Why Preserve It?
Nash Roderick: The Value of Wilderness (1978)
Why did US citizens feel the need to legally protect wilderness?
List of largest wilderness areas in the US