May 8, 2012

Simultaneous drought and flood?

Is the swamp still in deep drought …

Or is an early flood season already underway?

The hydrograph above shows the rapid rise in the water table at Raccoon Point following two consecutive weekends of substantial rain (totaling 9 inches for the month).  As a result, the cypress domes and even out into the marl prairies are flooded well a month in advance of normal.  Last year, the same level of flooding wasn't achieved until early August.

Answer: Yes and yes.

Two consecutive weekends has officially reflooded the cypress domes, and even up into the marl prairies in on the east side of Big Cypress Nat’l Preserve in Raccoon Point. The local rain gage recorded almost 9 inches of April rain. That’s a monthly total reminiscent of wet season month, but unlike the wet season – when the rains tend to be fairly well distributed (i.e. a little each day), most of this April’s total fell from just two events.


Three weeks ago I was walking in a dry apple forest.

Now the same pond apple forest is a foot deep!


Compare that to last year’s deep and protracted drought:

It took until early August to achieve a similar depth.

The above rain chart plots recent rainfall at Raccoon Point relative to the basin-wide long term statistics.  As you can see, the 9 inches recorded in April is well above the long-term April norm (2 inches).  Eight of the nine inches fell in just two weeks.  Preserve wide, April rains averaged around 4 inches.  That’s still two inches above the long-term 2-inch April norm, but not enough to lift all areas of the swamp out of spring drought mode.

But Raccoon Point is the exception:

Much of the rest of the swamp is still down in dry season drought.

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