On dangerous air & the damnation of cyanobacteria.

On dangerous air & the damnation of cyanobacteria.

During the acute phase of the Covid-19 pandemic, I kept thinking of Margarita Engle’s poem “More Dangerous Air.” The title seemed particularly resonant, and its a beautiful poem about growing up in an atmosphere of fear.

Newsmen call it the Cuban Missile Crisis.

Teachers say it’s the end of the world.

Engle documents the way we might flail, attempting to protect ourselves & our loved ones. We know enough to be afraid; we don’t yet know enough to be safe.

Early in the pandemic, people left their groceries on the front steps for days before bringing the bags inside. A year in, we were still needlessly scrubbing surfaces with toxic chemicals.


During the missile crisis, school children practiced fire drills, earthquake drills, tornado drills, air raid drills. (They didn’t yet need the contemporary era’s most awful: the active shooter drills.)

Hide under a desk.

Pretend that furniture is enough

to protect us against perilous flames.

Radiation. Contamination. Toxic breath.

The blasts are dangerous. But warfare with atomic weapons is different from other forms of violence. A bomb might kill you, suddenly; the poisoned air might kill you, slowly; the poisoned ground might maim generations yet unborn.

Each air-raid drill is sheer terror,

but some kids giggle.

They don’t believe that death

is real.

Radiation is invisible. Marie Curie didn’t know that it would kill her. Rosalind Franklin didn’t know that it would kill her.

We know, now. At least, some of us do.

Others – including a perilously large cadre of politicians – still think we ought to stockpile a behemoth nuclear arsenal.

Nuclear bomb: photograph by Kelly Michals on flickr.


Viruses are invisible. And they act slowly. Breathe in an invisible virus; a week later, you might begin to cough; three weeks later, your cough might worsen; a month after that seemingly innocuous breath in which you sucked a microscopic package of genetic code into your lungs, you might be in the hospital, or worse.

Connecting an eventual death to that first dangerous breath is actually a tricky cognitive feat! The time lag confuses us. It’s much easier for human minds to draw conclusions about closely consecutive events – a vaccine followed within hours or days by fever or heart problems.


Greenhouse gases are also invisible. If we drive past a power plant, we might see plumes rising from the towers, but we can’t see poison spilling from our cars, our refrigerators, our air conditioners, our meals. This is just good food on a plate! It doesn’t look like danger.

But we are changing the air, dramatically, in ways that might poison us all. Or – which is perhaps worse – in ways that might not affect us so much, but might make this planet inhospitable to our unborn grandchildren. Perhaps we will be fine. It’s humans born twenty years from now, or fifty years from now, who will suffer more.


Each individual can take action. You, as an individual, could fly less, buy less, eat plants.

And yet.

You, as an individual, can only do so much.

When I hide under my frail school desk,

my heart grows as rough and brittle

as the slab of wood

that fails to protect me

from reality’s



We aren’t the first. Go outside and look around – the vibrant bursts of summer green are delightfully entrancing.

Our minds are plastic things – we make ourselves through the ways we live – but certain scripts were sculpted by our ancestry. Over hundreds of millions of years, the bearers of certain types of brains were more likely to be successful in life.

Creatures like us – who need air to breath, water to drink, shelter from sun and cold – often feel an innate love for the way summer light plays over a heady mix of blue and green.

We need all that green. The plants, the trees, the algae: for humans to survive the climate crisis we’ve been making, we’re depending on them. We need them to eat carbon dioxide from the air, and drink in hydrogen atoms from water, and toss back oxygen for us to breathe.

We’ve been poisoning the air, and they might save us.

Which is ironic, in a way. Because all that green – they wrought our planet’s first global devastation.

Saving us all this time would be like a form of penance.


Early in our planet’s history, there was very little oxygen in the air. Which was a good thing for the organisms living then! Oxygen is a very dangerous molecule. When we fall apart with age, it’s largely because “oxidative damage” accumulates in our cells. When grocery stores market a new type of berry as a “superfood,” they often extol its abundance of “antioxidants,” small molecules that might protect us from the ravages of oxygen.

The first living organisms were anaerobic: they did not need, and could not tolerate, oxygen. They obtained energy from sulfur vents or various other chemicals.

But then a particular type of bacteria – cyanobacteria – evolved a way to eat air, pulling energy from sunlight. This was the precursor to modern photosynthesis. Cyanobacteria began to fill the air with (poisonous!) oxygen as waste.

Many years passed safely, though. There was abundant iron then, on land and in the seas – iron drew down oxygen to rust.

Approximately two billion years passed without incident. All that iron buffered our planet’s atmosphere! It must have seemed as though the cyanobacteria could excrete a nearly infinite amount!

But then they reached a tipping point. The iron had all become iron oxides. The concentration of oxygen in the air rose dramatically. This hyper-reactive poison killed almost everything alive.


Perhaps cyanobacteria were punished for what they’d done. By filling the world with oxygen, they enabled the evolution of organisms with higher metabolisms. Creatures who lived faster, shorter lives, turbocharged by all that dangerous air. And these creatures – our forebears – nearly grazed their enablers out of existence.

Cyanobacteria were once masters of the universe. Then they were food.

And they were imprisoned within the cells of plants. Look up at a tree – each green leaf is a holding cell, brimming with cyanobacteria who are no longer free to live on their own. Grasses, ferns, flowers – every photosynthetic cell home to perhaps dozens of chloroplasts, the descendants of those who caused our planet’s first mass extinction.

A few outlaws linger in the ocean. Some cyanobactera still pumping oxygen into the air, the lethal poison that’s gulped so greedily by human lungs. Their lethal poison now enables our growth, our flourishing, our reckless abasement of the world.

And we are poisoning the air in turn, albeit in a very different way. In our quest to use many years’ stored sunlight each year, we dig up & burn the subterranean remnants of long-dead plants. The prison cells in which cyanobacteria once lived and died, entombed for millions of years within the earth, now the fuel for our own self-imposed damnation. The concentration of carbon dioxide in the air is slowly rising. Our atmosphere is buffered; for a while, our world will seem unchanged. Until, suddenly, it doesn’t.

Some species, surely, will survive. Will thrive in the hotter, swingier, stormier world we’re making.

It likely won’t be us.

On bistability.

On bistability.

Over the course of ten days in March, our weather in Bloomington careened from the mid-seventies down to the teens with a few inches of blustery snow.  Twice!  Two sudden spells of unexpected summer, two of icy winter.

I do a lot of walking on evenings and weekends, and during that month I was often inappropriately dressed.  Shivering or sweating.

Bloomington is located at the midpoint between two major air currents, one from the south that carries warm wet gulf weather, one from the north that brings dry polar air.  We skip a lot of the mild in-between temperatures that people associate with spring or fall.  Instead, our weather flops back and forth between mirroring balmy Kentucky or blustery upper Michigan.

We’re always breathing somebody else’s air.

Our town is at 40 degrees North, right where the air currents get all tug-o-war-y.

In science, this sort of phenomenon is called “bistability.”  Something like temperature, which seems like it could slide around gradually, instead lurches from one state to the next.

Like alcoholism, in a way.  Many people can drink a glass or two of wine with dinner.  For an alcoholic, that would be dangerous.  With alcoholism, the choices narrow to either staying sober or slipping into a binge.  The glass or two of wine at dinner becomes empty bottles and an unremembered night.

A buddy of mine explained why he never touched the stuff this way: “I realized that every time I’d drink, I’d end up with a needle sticking out of my arm.”

Image by Imagens Evangélicas on Flickr.

Or there’s the more common example of a light switch.  Unless you install a dimmer, the room suddenly flips from dim to bright when the wall switch crosses its midpoint.

Image by Martin Cathrae on Flickr.

The input — the position of the switch — moves fluidly through space when you flick it.  Its height takes on all the intermediate values.  The output — brightness of the room — does not.  One moment, the room is dark.  The next, there is light.


Bistability is cool.  Also: hugely important.  And also: devilishly tricky to understand.

First, the importance.  In addition to weather systems and alcoholic binges and the working of common electronics, bistability rules our brains.  Your brain contains some hundred billion spidery cells called neurons, and your thoughts happen when these neurons begin “firing” in a particular pattern.  Each neuron is like a machine that collects information at one end and sends a message at the other.  The messages are bland, though.  Each message is either sent or not.  That message is called “firing.”

(To a rough approximation, at least — imagine interacting with a dog that only knows one word, “woof.”  It can still convey slightly different information by saying “woof” at different rates.  You might respond differently if you heard your dog say “woof” once versus saying “woof” every three seconds for a minute.  Similarly, neurons can convey different messages with different rates of firing.)

Each neuron is bistable.  Pulse.  No pulse.  Just like a light.  The room is dark.  The room is light.  If you were fifteen & at boarding school, maybe you’d have a lightswitch rave.  “B., you stand there and toggle it, we’ll dance.”  With no intermediate brightness, the flickering makes everyone disoriented.  You’d hardly need drugs!  Except, if you were fifteen & at boarding school, you’d probably have little trouble finding drugs.

CaptureNeurons are similarly switchlike because the act of firing also causes firing.  Once a threshold is crossed, the behavior feeds itself.  Having a drink makes our beleaguered alcoholic want to have a drink.

And bistability pops up in many other fields.  In economics, the rich get richer and the poor get poorer.  Having money makes it easier to get money.  In astronomy, lonely matter becomes more thoroughly alone.  Empty space expands faster than regions with mass, creating isolated pockets of stuff.  In either case, we end with rampant inequality.  You’ll have a lot of money, or none; you’ll have many neighbors, or none.  Bistability carves out the middle.

I think it’s important for all of us to learn a little about bistability because the knowledge engenders a much-needed skepticism when reading about climate change.  Although when many others write sentences that include both “climate change” and “skepticism” they mean that we should not be afraid.  My point is that we should be more afraid.

logo-cop21-enAt the Paris meeting, many countries agreed that we should try to prevent temperatures from climbing more than 2 degrees.  The assumption being that a 2 degree change will leave us safe.

It might.

The problem is that our world’s climate is in many ways like a light switch.  Sans dimmer.  As our weather changes, plant growth will be affected, which will change the rate at which plants hoover gases out of the atmosphere.  A crude guess is: hot weather, fewer plants, less carbon pulled from the air by plants, even hotter weather in the future.

Or hot weather might melt arctic ice, and that new influx of water could change the pattern of underwater currents.  This would leave many people upset.  If western Europe weren’t in the path of a steady flow of northbound tropic water, it’d be much colder.  “Global warming” can cause local temperatures to plummet.

Without that big red arrow having that particular shape (and yes, it could change), living in Western Europe would be a lot less fun.

And the melting ice would cause Miami to disappear.  Maybe parts of New York City.

The devilish thing about bistability?  Tiny misunderstandings lead to huge mistakes in our predictions.  If someone holds a dimmer switch midway up, you can probably guess how bright the room will be.  “Medium bright!”  With a standard switch, you would have much less confidence in your prediction.  Let’s say you’re cooking dinner.  If a toddler climbs up on a chair and starts fiddling with the light switch, claiming she’ll only move it “a little bit,” do you expect the room to stay lit?

thermometerGlobal climate has such nonlinear inputs that it should be no easier to predict.  It’s hard to put much confidence in anyone’s claiming to know what will happen if temperatures change 2 degrees, or 1.5 degrees, or 4 degrees…

That said, there’s plenty we can do.  Us regular people can make a difference without involving any politicians, just by thinking about what we eat.  The “big dream” goal is to cut emissions by 60% to 80%.  But animal agriculture accounts for somewhere between 10% to 50% of global emissions. (The low end of that range was estimated using outdated numbers for farm animals and assuming that cows don’t breath — the high end is equally unrealistic because it assumes all our farm animals would instantly disappear with their grazing land reverting to natural forests.)  Eat more vegetables for dinner and you’re already making a big change.