On the pace of environmental change (and boiling frogs)

Environmental disasters catch our attention.  Our ears perk up when something dramatic happens, like the BP oil spill in the Gulf of Mexico or the Fukushima nuclear plant disaster.  It’s the same with natural disasters like hurricanes, tornadoes, and ice storms.  And we seem to respond even more strongly to disasters when they can be seen (and when good photo opportunities are available).  It’s just the way our brains tend to work. 

Fortunately, these kinds of fast-paced, environmental disasters don’t happen that often.

Instead, environmental changes tend to occur slowly and act over longer periods of time.  Today, we’re in the middle of a lot of really big environmental changes: loss of biodiversity, changing climate, air and water pollution, deforestation, and so on.  Many of them have been going on for decades or longer, and their impact on our lives is much larger than one oil spill.

But we aren’t as likely to pay such close attention to these kinds of slowly-evolving events.  That’s where the story about boiling frogs comes in …

Briefly, the story goes like this:  If a frog jumps into a pot of boiling water, it will quickly jump back out (damaged, perhaps, but let’s not think about that).  Because the frog immediately recognizes that it was in a dire situation, it does something to get out of it.  Now, suppose a frog jumps into a pot of cool water, which is then slowly heated up until the water boils.  The frog will sit there, not noticing that the water is slowly heating up, and it will die when the water gets too hot.

This is a well-known metaphor … enough so that it has its own Wikipedia entry.  Al Gore used the boiling frog story in “An Inconvenient Truth” to make the case that we are acting like frogs in water that is slowly heating up.  Paul Krugman used the story  to discuss both environmental and economic issues that are slowly creeping forward.  Actually, economists use the same boiling frog story to make the point that people tend to ignore changes that happen slowly.  (So, if you want to make a change in the recipe of your famous secret sauce, do it slowly and people might not notice.)

One problem with the story is that it’s not true.  Frogs will jump out of the pot when its temperature rises high enough (hopefully we are as smart).  Apparently there were some 19th century studies that were inconclusive on the topic, but they were cited and then the story turned into an urban myth.  But it’s a good story … used to grab your attention (and the reason I decided to use it in this post).

The overall point is still very important … we are not likely to pay attention to environmental events that are slow-moving or develop over long periods of time.  And this is the reality of how most environmental changes play out — very slowly, over decades or longer, like climate change, deforestation, or the extinction of species.

Of course, “slow-moving” depends on your perspective.  These environmental events are happening incredibly fast if you look over hundreds or thousands of years.  If you compare conditions today with the past you would notice a huge difference, but someone living though it might barely notice. 

We’re starting to understand just how extensive this phenomenon is.  For example, in the 1990s a group of fisheries biologists were grappling with the fact that certain populations of fish, cod in particular, had declined to such low levels that fishing needed to be stopped for a while to allow them to recover.  So they start investigating historical population sizes of fish, before fishing pressures had increased.  What they found was surprising.  Their estimates of fish  populations just a few decades ago (and the ones they were thinking of using) were already considerably depleted when you compared them with even earlier estimates.  Daniel Pauly first described the phenomenon this way:

“… each generation of fisheries scientist accepts as a baseline the stock size and species composition that occurred at the beginning of their careers, and uses this to evaluate changes. When the next generation [of fisheries scientist] starts its career, the stocks have further declined, but it is the stocks at that time that serve as a new baseline. The result obviously is a gradual shift of the baseline” (Pauly 1995)

Pauly defined a new concept to describe what was happening: “shifting baseline syndrome”.  Essentially, we had “forgotten” how many fish there used to be as we adjusted our idea of normal fish population sizes.  This is now a well-established concept in marine science and a recent book details some more recent developments (Jackson 2011).

A similar concept is “landscape amnesia”, which I particularly like.  Jared Diamond describes “landscape amnesia” in his book Collapse to explain why the people on Easter Island might not have thought twice about cutting down the last tree on their island … even though the island was originally densely forested.  Through ecological and archaeological studies we know that deforestation of the island was dramatic, but this is our perspective looking back.  The deforestation actually took place over several hundred years, so people living on the island when the last tree was cut had no collective memory of the original dense forest.  They had accepted the idea that their island was essentially treeless, so it wasn’t important to preserve the last one.

These examples, and others, come from our emerging understanding of the more realistic (and fascinating) way that most environmental changes tend to unfold … slowly and tied in with our human perceptions.

Are these kinds of stories as compelling as environmental disasters?  Or boiling frogs?  Are they interesting enough to catch your attention? I’m not sure, but they’re the kinds of examples I’d rather be looking into. 

Diamond, J. 2005.  Collapse: How societies choose to fail or succeed.  Penguin Books.

Jackson et al. 2011.  Shifting Baselines.  Island Press.

Pauly, D. 1995. Anecdotes and the shifting baseline syndrome of fisheries. Trends in Ecology and Evolution 10, 430.