Nov 8, 2011

Icebergs spotted in Everglades?

A common problem with hydrographs?

Trying to say it all without showing too much.
Everglades hydrology requires
keeping a close eye on lots of parameters!

Take for instance Water Conservation Area 3A (WCA3A.)

Its regulatory water stage has increased by over a foot in the past few weeks. But you can’t tell that story by just a single line. Rather, the single line, the bright colored blue one in the center of the multi-parameter hydrograph above, has to be painted relative to the historical statistics (1993 to present,) land surface of the various major habitat types (slough, ridge, bayhead, tree island and hammock,) regulatory rules for operating the reservoir (Zones A thorugh E,) and elevation of the water surface in feet above sea level.

That’s a lot of things to keep straight on one page.


Then there’s the reason why the bright blue water line rose to begin with: Rainfall. Or 11 inches of it in October to be exact. Monthly rainfall is shown by the blue bar chart at the top of the graph, with the gray shading in the background showing the 25-year historical statistics. Turns out the long-term median is only 3.5 inches of October rain.

That means this October got three times the normal dose.

Flow is a proven antidote
for what ails the Glades.

Then of course there are structural flows.

You can’t understand the rise and fall of the bright blue water level line without knowing when and how much water is inflowing into WCA3A through, say, the S-11s and leaving by way of its southern outflows the S-12s A, B, C and D.


Then come the comparisons to other basins in the Glades.

Or in other words, how does the blue water line in WCA3A compared to water depths in interconnected basins WCA3B, Shark Slough, WCA2 and Loxahatchee NWR?

Answer: WCA3A is deeper by a foot!

Talk about vicissitudes:

Last spring was the deepest drought in twenty years.
Now it's the wettest fall in three years!

A preliminary comparison is not complete without a historical view.

The calendar graph above provides a easy way to compare and contrast this year’s rise and fall of water stage to similar hydrologic vicissitudes and durations of previous years and decades past.


A complicated as it is to graph ...

It's also just the tip of the hydrologic iceberg, too.

2 comments:

Robert V. Sobczak said...

The question that remains after assimilating all your information is did it rain more in WCA-3A than in the other areas that water depths are shown, how different were inflows and outflows to each of the different areas, and
finally which area displays the depth class distribution which could represent an ecological target both now and in the not so distant future given anticipated climate. If we can answer these questions then the managers just look at us and say we are not distilling it into a multi-purpose management framework.

So the answer to managers is simple. Rainfall was not the same, structural inflows were significantly different and if you want to ameliorate EAA flood discharges to WCA-2A and WCA-3A then you need to reduce EAA
discharges by acquiring 125,000 to 175,000 acres of agricultural lands, increase the size of EAA STA to 75,000 acres, and increase flows to WCA-3B and Northeast Shark Slough. But we know that the state and federal government are never going to do this so status quo.

Have a great holiday and don't forget to fly old glory.

Robert V. Sobczak said...

I received the comment above by e-mail.