Nature worth "$145 trillion per year" to humanity

Nature isn't priceless.  In fact, economists can give it quite a specific price: about $145 trillion per year, if the net value of all ecosystem services is tallied up.

What's a nice sunset worth?  (photo by William Laurance)

Yes, that's 145 trillion dollars -- as in 145 with 12 zeros behind it. 

This new finding--which you can download free here--comes from a major analysis of global ecosystem services led by economist Robert Costanza of Australian National University.

Ecosystem services include a wide array of things such as carbon storage, crop pollination, fisheries, recreational opportunities, flood mitigation, and the provisioning of clean water.

While the new result underscores the astonishingly important role that nature plays in human welfare, there's also a kicker: the annual value of ecosystem services has declined by up to $20 trillion between 2007 and 2011, according to Costanza and colleagues, principally because of habitat destruction and other land-use changes.  And that erosion in value is ongoing.

Putting a price on nature is tricky and inevitably some people will object to the idea.  For instance, how can you place a dollar value on having clean air to breathe, or a wilderness to hike in, or hearing a rare bird sing?

But doing so underscores an important point: Even in the most utilitarian sense, nature has incredible value to humanity, and that value is being eroded.  Like any valuable resource, we're nothing short of foolish if we merely squander it.