Re: a simple(?) probability question...


Joe wrote:

On Jan 21, 8:23 am, "Dirk Van de moortel"
<dirkvandemoor...@xxxxxxxxxxxxxxxxxxxxxxxxxxx> wrote:

Have a look at the Poisson process and see if
it helps:
http://en.wikipedia.org/wiki/Poisson_distribution
Try to understand how it can be applied in this case,
i.o.w. what would k and lambda be in this case?
What do you find?

Dirk Vdm

Your reasoning is faulty on this. A 50 year flood is not
the same intensity as a 100 year flood. So by analogy in
definition [...]

What is the definition of a 100-year storm?
Google is your friend.

http://www.google.com/search?hl=en&q=%22100+year+storm%22

http://climate.umn.edu/doc/misc/100year.htm
: One of the more confusing phrases used in meteorology
: and hydrology is "100-year storm". The phrase implies
: that an intense rainstorm dubbed as an "100-year" event
: brings rainfall totals heretofore unseen for 100 years,
: and not to be experienced again for another century.
: This is a logical, but incorrect conclusion to draw
: from the phrase. A "100-year storm" drops rainfall
: totals that had a one percent probability of occurring
: at that location that year. Encountering a "100-year
: storm" on one day does nothing to change your chances
: of seeing the same amount of precipitation the very
: next day.

HTH.

[...] a 50 year
flood is a flood expected to occur in 50 years which means it is in
fact has a probability of 1.0 [...]

This happens not to be the case.

[...] and has no bearing on the 50th year
probability of a 100 years storm.
.

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