Feb 25, 2010

Net rain

Rain may not always put us in the best spirits,

And on occasion may dampen our day,

But is it appropriate for me to describe it as “gross.”


What I mean to say is that the water cycle is all about budgets – and not all that different from the way we balance our bank books with inflowing money and out.

Gross is what we earn;

Net is what makes it into our pocket books
(not to mention all the bills we have to pay).



Meteorologically speaking,

Gross is the total amount of water that lands in the rain bucket,

Whereas net is what makes it down into the water table below.



The hot sun, desiccating wind and thirsty roots all nibble away at the gross.

We call that evapotranspiration.




What happens when evapotranspiration exceeds rainfall?

The water table falls …

Or in other words, a “negative” net.

2 comments:

Stephen Tremp said...

You learn something new every day. Now I know what evapotranspiration.
means. I was in Florida once for a family vacation in the eighth grade. Saw Disneyworld, Bush Gardens, and other tourist spots.

Stephen Tremp

Robert V. Sobczak said...

Thanks Stephen. I'm amazed myself how the water cycle always has something new to reveal. It's in a state of constant flux.