End of summer?

The end of summer is near!

Or rather, is the end of summer near?


The late arrival of Labor Day this year begs the question.

Will that affect the weather?

Probably not. But I assure you it will affect the wardrobes you see on the street.



I remember living up north when the fine denizens of the New England land mass perfectly timed their transition into autumn attire by the arrival of the holiday weekend.

It had less to do with a fine sense of fall fashion than a utilitarian practicality of keeping warm – temperatures quite literally drop off the side of the summer table through the month of September.


That happened last year in Boston:

Daytimes highs fell from a T-shirt worthy 80 degree heat into the cool crispness of the high 50s by month’s end.



Compare that to Florida.

Labor Day comes and goes without much change in the weather:

It’s a waiting game until October.

In Tallahassee (the closest you can get to the continent and still say you’re in Florida), October 2008 started with daytime highs in the mid 80s and ended in the mid 60s.

How about south Florida?

The tell tale sign that fall has arrived in Naples is the late October descent of night time lows below the 60º F degree line.

When that happens, I go out into the night air, relieved that summer is over, and breathe in deep.


And usually in “shorts and T-shirt” I might add …

That’s about the extent of fall fashion in south Florida.

sheetflow in motion

Invisible flow

In the summer the sheet flow spreads out far and wide.

It’s flowing, you just can’t see it …

Or rather, you can see it, but you have to know where to look.



An engineer will take you to the side of one of south Florida’s famously straight roads and point to a structure: “See, it’s flowing, at about a couple hundred cubic feet per second … I can get you the exact numbers back in the office.”

A scientist will walk you off road – behind the cypress curtain where the trees scatter, the trunks thicken, then the knees rise high – to where the canopy opens into a lattice pattern of light shining through craggy swamp apple branches:

“See, it’s flowing, at only a few inches per second (at most) … how does a hydrologist measure this type of flow anyhow?”



The scientist will ruminate that “the sheet flow would be running deeper and longer if there wasn’t a levee upstream.”

The engineer will respond that “we can adjust the gates to let out more water to the critters if only the biologists would tell us how much.”



Where do the worlds of the engineers and scientists overlap?

I just got back from Belgium, where everyone speaks everyone’s language, and where rules are, apparently, only loosely obeyed.

“It’s not that Belgian’s break the rules, we’re just creative in how we follow them,” I was told,

Followed by a clarification:

“But it’s completely different in Holland. It’s as flat as a pancake over there … just like the Everglades. You should go there someday.”



Maybe next time maybe I will.

A hydrologist is part scientist and part engineer you know!


I'm sure that on top of any number of its lowland levees that I'd see "water in motion" -- even if I have to turn backwards toward the "ebb and flow" of the great North Sea to see it.

Those levees were built to keep the saltwater out, not as -- in the case of the Everglades -- to channel the freshwater away and around.

Levees are quite common, but there's only one Everglades.

clear view of a cloud shell

Cloud carapace

Is the water cycle ever blurry?

Yes, it’s called fog.



Fog of course is nothing but a low altitude cloud.

The truth is that all clouds are blurry if you’re on the inside of them looking out, no matter how sharp or wispy the edges may seem from a distance. In fact it’s the clouds with the sharpest edges that are the bumpiest when you fly through them:

That’s called turbulence.



It’s a universal yearning to rise above the fog, but also maddening – blue sky is practically in grasp a few feet above the tree tops but it might as well be a world away.

Fog is safe in the sense it won’t cause turbulence on the ground (thank god!), but it is a safety hazard to drive through, especially with headlights at night through pea soup.

And it’s among the more difficult subjects to photograph: Besides being blurry, the lighting is muted and drab, and usually a “waste of film.”

(Does that expression still apply with digital cameras?)



I spotted this impressive cloud the other afternoon.

It was blurry like fog, but high in the sky and grabbing the luminescence of the late day sun. While it had the look of once being full of turbulence, the energy that formed it had evacuated its premises.



Call it a cloud carapace:

An instance of the water cycle shedding its exoskeleton and moving on.

Sheering winds had since moved in to smudge its side walls.


It was as clear a view of blurry as I’d ever seen.

water cycle carnival

Everyone's a winner!

The water cycle can be fun!

We forget that.

The newspapers will have you believe that all is wrong with the water, that it’s flowing the wrong way, or afoul with the wrong stuff, or out of balance with how it once was.



Not that I don’t believe the papers – I do!

I read them all the time, and learn a lot from them.

(And thank the water gods for the internet. I get stories from up and down both coasts and every corner of the peninsula delivered right to my Google Reader.)



A colleague of mine back in my Arizona days of old, when I was first cutting my teeth in the profession, was continually expressing frustration about the newspapers:

“It’s a bunch of lies. Nothing but lies,” he would proclaim, paper in hand pointing to the headline sprawled across the cover.

Then he’d go on to explain further: “I’ve never read a story in the paper about something that I know well in which I haven’t found something wrong with it, or missing, or misleading,” capped off with a conclusive – “And that’s just the stories I know!”

By extrapolation, he applied that same skepticism to every story head ever read in a newspaper.





My gripe with the papers isn’t that.

What bothers me is what I call the “Tragedy of the Headline.”

A topic turns red hot for a day or two, and then it goes away. Weeks, months pass without another peep:

The issue lurks in silence.

And that’s just the issues that are reported. (I’m sure there are countless others that never make the press.)




The true story of course never sleeps; you just have to take a few extra steps beyond the printed page to find it. (And yes, it may involve getting your feet wet!)

Anyone who boats, or fishes, or pours a fresh glass of tap water over ice on a hot summer day knows that. The precious liquid stuff is out there in many forms … for us to both enjoy and safe guard.

The two go hand in hand.


That brings me full circle about how fun the water cycle can be:

It’s like fishing for ducks.



“Everyone’s a Winner” when you get your feet wet in the water cycle,

Or as they say in French – “Tourjours Gagnet.”

red sky at night

Sea of Okeechobee

Sometimes it pays to do the math.

I was hiking along the Gunpowder River with my brother, not too far from Kingsville Maryland, when we came across this sign.



According to my calculations, that makes it almost 100 times larger than the 670 square miles that make up Lake Okeechobee.

Okeechobee’s upstream watershed is 6 times larger than the area of the lake.


But the funny thing is, when you look out at Lake Okeechobee – it looks like a sea. When you do the same to the Chesapeake, it looks exactly like its name says it is: a bay.


That goes to show:

When it comes to big waters, don’t always believe what you see – there’s often more than meets the eye ...

Or do I mean “less?”

mineral analysis in milligrams per liter

Teaspoon hydrology

You’ve heard of “mass” confusion,

But even more confounding is the curious case of trying to figure out mass “per volume” at very low concentrations.


For instance, we know that sea water is salty, but just how “salty” is it?

In scientific terms, it’s 35 parts per thousand (ppt) “salty.”

The recipe in your kitchen would call for adding 26 teaspoons of salt per gallon of water. (Easy enough, I have both.)


How about parts per million (ppm)?

Now we’re getting dilute.

The recipe calls for adding 1 teaspoon to sauce pan the size of 31 rain barrels (at 42.5 gallons per barrel).


Can anything that dilute harm us?

Nitrate levels at a concentration of 10 ppm is cause for alarm for one. (That's one reason why people buy bottled water instead.)



How about parts per billion (ppb)?

(Now this will test how well equipped we are in our kitchen!)

This recipe calls for adding 1 teaspoon (good we already have that one) to a lobster pot the size of 2 Olympic swimming pools.


Can you even measure something that dilute?

In the Everglades, total phosphorus in concentrations above 10 ppb is considered a pollutant.


As confusing as all this seems (even to me), I’m glad to know that I am at least semi-well equipped as a hydrologist (going out into the world) if I have nothing else but a “teaspoon” in my hydrologic satchel.

It’s better than the alternative:
Carrying the water!

free-flowing
old Florida Everglades

Florida's "perfect storm"

Does a rainy May make a wet season?

Not if its deluges are too close to the coast (i.e. Daytona) and not if the core wet-season months that follow fall sub par (Naples and Ft Myers).



Prior to canals and levees, waters spread out amply, seeped down slowly, and flowed south sluggishly … in the slow-motion hydrology ride we call sheet flow.

Sheet flow is sort of like the syrup you pour over a pancake.


That molasses-like speed has nothing to do with Florida’s water – it’s as fast as any – but everything to do with the lay of the land.

It’s flat, low, and channel-less.



Enter canals and levees:

They drain water out to sea (fast!) and also constrain the foot print water can spread out on.



That’s resulted in many sloughs and strands becoming disconnected from their upstream ‘slow-drip” sources, and turned coastal estuaries into sacrificial dumping grounds where the big rain weeks and months short circuit through before getting lost to sea.

Restoration lies in finding ways to hold back the water from the coast (a technical term hydrologists call “inland storage”), and saving it so it can be soaked in and slow dripped south.





In the meantime, the canals and levees have warped our thinking about the vicissitudes of rainfall:

We hope beyond hope for the perfect rain month, season, and year to replenish our watersheds to the precise thresholds we divine … all the while knowing that the weather rarely falls from the sky in such tidy packages.


I call that the Everglades’ version of waiting around for the “perfect storm.”

Of course other people may have different definitions for that term:

After all, this is hurricane season.



Click here to see rain charts for your area, data courtesy of South Florida Water Management District (weather).

levee entrance

Open for business

The S344 is open.



I mention that is not so much because it’s an unusual occurrence, (although it only happens for a handful of weeks of each summer wet season) …

Nor because it unleashes large volumes of water:

It’s only flowing at a rate of around 150 cubic feet per second. Over the course of a day that would stack a 300 ft deep pool of water across the Miami Dolphins 1-acre football field.


We have hills higher than that in Florida!

Actually, only one of them – it’s called Britton Hill. At 344 feet it is the highest spot in the state.


Still, in south Florida water terms, that’s not a lot of water.

What makes it important is that it crosses over the watershed line that separates the Everglades from the Big Cypress, or rather under it.

The modern day divide is a levee called the L-28.



The levee is 14 miles long, unusually high considering the shallowness of the water below, and very narrow on its crown, making it a precarious drive. (One wrong turn and you’ll roll down its steep slope.)

But most of all it’s closed … unless you have a key.



That’s why I mention that the S344 is open.

Otherwise there’s a good chance we wouldn’t know.

closest we have to a free-flowing spring in south Florida

Ever growing list

I always knew that Florida had a long list of springs,

What I didn’t realize is that they are both “cold” and “warm.”



During the summer they are cold – Florida’s original and all-natural air conditioning (see article) – but come winter time, the Fahrenheit-scale inversion reverses:

Magically they turn “warm” … or so it seems.

The trick is that their liquid source – ground water – stays the same temperature all year round.


For what Florida lacks in mountains, it makes up for in springs – over 700 at last count – and here’s the kicker:

The most 1st magnitude springs of any other state.



What does it take to be a 1st magnitude spring?

To make that list the spring has to up well 100 cubic feet of water per second. That’s enough water to fill up 98 Olympic size swimming pools per day, or in “Fenway Park” units (if you fill the area of fair play up the top of the Green Monster), around 2.5 per day.

The highest flowing spring is Spring Creek. It fills up 53 Fenways (or alternatively 1,962 Olympic swimming pools) per day.



Even the 3rd order springs are impressive:

To make that list they need to output 1 cubic foot per second … or in 42.5 gallon water barrel units, around 450 per minute.

That’s a lot of water day after day after day … cool in the summer, warm in the winter.



Did I mention they flow at pretty much the same rate for most of the year too?

Add “steady” to the list.

lichen on a cypress at the swamp water line

Plant that wasn't there

Probably the earliest classification system we learn as children, or one of them at least, is categorization of the world around us into one of the Big Three: “animal, mineral, plant.”

That was Lesson One.



Lesson Two was exceptions to that rule, with the puzzling case of the lichen (is it a plant, or isn’t it?) usually being presented as Exhibit A.

Fast forward three decades later and the “plant” – or whatever it is – still evokes a sense of mystery.



What I like most about lichen is that they are out there everywhere, usually right in front of our noses, but isn't it so often the case that we see right past them.

That makes lichens the plant (or whatever it is) ... "that wasn't there."

short video
of rain gage
at Gum slough,
then flying north,


photo of
Tamiami Trail
east of Oasis

Nature's slowest drain

Are all rain storms equal?

That depends on what side of the drain spout you are on.



Chances are it hits the roof top at a fairly even pace, but where it goes from there is a function of the pitch and swales of the roof.

In that way, not all drain spouts are created equal.

One may flow like gang busters right next to another that barely dribbles.



We have the same issue along Florida’s famed Tamiami Trail.

The S12s carry the heavy load over in the Everglades, but right next door – in the Big Cypress – flows are funneled under a series of smaller bridges.

Like the drain spouts, they flow unevenly from one to the next,



That has nothing to do with the rains:

They fall more or less evenly in the watersheds upstream:

About 55 inches worth per year.



That’s a lot of water on any roof, let alone the Everglades, which is as flat as a floor board and as wide as an eye can see.