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EdBannister
Mountain climber
13,000 feet
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Jan 11, 2017 - 09:57am PT
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Ed Hartouni
Sir, If you look at Saturday morning, I said it then .
And on Monday my posture was not I told you so, I responded.
You guys are looking at stage, or river height as if it were volume of discharge.
Saturday morning the prediction was about 23,000 cfs reality was 10,000.
The error was not slightly less than double the real number
It was significantly more.
Bottom line
There are some, no matter what the degree of inaccuracy,
who are not willing to admit an error.
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Ed Hartouni
Trad climber
Livermore, CA
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Jan 11, 2017 - 10:20am PT
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you wrote:
yes i said i was concerned about Monday, and i was wrong to have a concern.
But it was a concern about a threat, i assigned no number, made no prediction for Monday.
NOAH Predicted discharge was originally about 23,000 cfs
actual peak discharge was about 10,000 cfs
Do you look at the fact that the estimate was 230% of reality?
Is there some percent error amount at which you will say they were wrong?
To me, a more than double inaccuracy, is inaccurate.
Yes, early warning was good, and we all hope for the safety and well being for all.
But will the people on the ground take the next number they are given seriously??
Probably not, I did not this time, and i was correct not to do so.
I looked at weather maps and radar and estimated less that 17 feet when the estimate was 23.1 feet.
You can't undo that.
the "estimate" was a running estimate changing in time both when it was going to happen and the river stage (and flow, etc.) the estimate was not a one time thing, and we that had the luxury to look every once and a while missed all the intermediate updates...
given that this was an event happening with uncertainty in realtime, I wonder what level of accuracy you'd expect, or more importantly, how you would define "accuracy" in this particular situation.
further, NOAA was doing this throughout the western watershed as the storm moved through the entire area... with many factors changing through out that time.
They aren't "undoing" anything, they take every storm and go back and crunch the numbers to help modify their forecast methodology.
Can you point to an "error"? I'm sure they would be happy to hear from you if you could.
You might also review the idea of variability, and uncertainty quantification, and the concepts of accuracy and precision.
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micronut
Trad climber
Fresno/Clovis, ca
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Jan 11, 2017 - 10:29am PT
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Big thanks to Ed and Clint for ruining this thread by turning it into a scientific discussion way over my head. I was hoping for a "Yeah she's gunna flood! Run for the hills!" style thread but this thing has degenerated into a bunch of facts, tables, methodologies and statistical rationale way over my pay grade. This thread needs more flood photos please!
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WBraun
climber
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Jan 11, 2017 - 10:34am PT
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There we go ,,,, now we're talkin :-)
And by the way, those predictions prevented the chaos that ensued during the 97 flood by the park planing preventative measures before the SHTF this time ......
Good job NOAA and all you scientists ......
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EdBannister
Mountain climber
13,000 feet
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Jan 11, 2017 - 10:34am PT
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Oh no Ed Hartouni, I was not saying you made an error.
NOAH made an error of 130%
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WBraun
climber
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Jan 11, 2017 - 10:38am PT
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EdBannister
The error was based on temperatures being higher then they became above 9000 feet.
During 97 flood, it rained at much higher altitudes.
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EdBannister
Mountain climber
13,000 feet
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Jan 11, 2017 - 10:47am PT
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Understood Werner,
I appreciate that NOAH did give a warning, and that Park Employees and all personnel worked in tough conditions to evacuate visitors and assure safety.
I don't have a beef, but i do recognize if you remove the emotionalism, and look at the prediction versus the result, there are some things to learn about the accuracy of the model.
If no one admits that, there will be no learning for next time.
As to Ed Hartouni references to Monday Morning Quarterbacking:
On Wednesday Jan 4, 9:52 pm when the model said 23.1 feet, i said less than 17 feet.. I went on record 4 days before, i don't recall anyone else's number before the fact... so that would take me off a list you might rightly be on.
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WBraun
climber
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Jan 11, 2017 - 11:02am PT
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but i do recognize if you remove the emotionalism
When I first saw the 23 feet prediction I thought ..... OH SH!T !!! we're all gonna die now :-)
The original 23 foot prediction before the start of the storm series was probably just based on the 97 epic?
Then they started adjusting their predictions as their real time data was updating and everyone was watching that with laser eyeballs .....
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cat t.
climber
california
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Jan 11, 2017 - 11:02am PT
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If no one admits that, there will be no learning for next time.
This is exactly what scientists are doing all the time: making a model, getting real world data that proves the model is incorrect in some way and modifying the model to accommodate that new information. Why the heck do you think that the scientists at NOAA are refusing to acknowledge new data? They were getting new data and modifying their predictions during the storm--they were doing exactly what you are asking for.
Over time they will get both 1) better data and 2) a better model. I think they're doing an awesome job.
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EdBannister
Mountain climber
13,000 feet
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Jan 11, 2017 - 11:06am PT
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Yes Cat, that is science.
i just amaze at "an individual" who will get mad at me, rather than admit there is more to learn.
and sorry, i don't think the original estimate was very good.
Dingus mistakenly said NOAH's prior 60% inaccuracy was from before satellites and radar.. not true.,
and, they were also 60% inaccurate, again, last week.
Edit: correction last week they were only 57% incorrect:
23,000 forecast 10,000 reality. 57% error
All i was suggesting last wednesday, was taking the 23.1' prediction with a grain of salt...
Science, is not smarter that what it claims to study... when the results do not match the "science" it is not the results that are incorrect.
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rbolton
Social climber
The home for...
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Jan 11, 2017 - 11:28am PT
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Is it just me or does anyone else find Ed Hartouni getting lectured on probability models and science kind of funny?
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tuolumne_tradster
Trad climber
Leading Edge of North American Plate
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Jan 11, 2017 - 11:30am PT
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NOAH predicted the flood even before science existed!! sorry couldn't resist ;-)
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EdBannister
Mountain climber
13,000 feet
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Jan 11, 2017 - 11:32am PT
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Tradster!!!
you are right!
I will sign off here on that note, and go post a photo...
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WBraun
climber
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Jan 11, 2017 - 12:44pm PT
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Your prediction of 17 feet, in the beginning, was way more accurate for sure with the data of how high it will rain .......
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aspendougy
Trad climber
Los Angeles, CA
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Jan 11, 2017 - 02:45pm PT
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NOAH or any other agency for that matter, would much rather overstate the threat and have more people flee, than understate it and have one person die as a result. For safety's sake, it is their duty to give a worst case scenario, then if their predictions are off, they get criticized, but everyone is still alive. All in all, they did a good job; the mathematics and the level of uncertainty is huge with these big weather systems.
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toejahm
Trad climber
Chatsworth, CA
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Jan 11, 2017 - 02:49pm PT
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W Braun
What elevation did the snow line end up at this time? I lived in Wawona during the 97 flood. I can attest it was quite an event. I have photos of the swinging bridge just before the tree hit it and the aftermath. I will search tonight to see if I can find the photos. I know they're not digital, but should be worth finding.
peace,
Kenny
p.s. For those who don't know that was the year of extremes: It brought the 36" Sierra cement storm that knocked down so many trees that I believe we were cut off for a good week and also the Mono wind storm that leveled Norman May's home (RIP Norm) along with countless other homes. Norm did survive the storm, but the blue goose didn't.
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Ed Hartouni
Trad climber
Livermore, CA
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Jan 11, 2017 - 10:21pm PT
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what were they "wrong" about?
There are a sequence of forecasts regarding the storm,
819 AM PLT TUE JAN 03 2017
(POHC1) MAX 4.2 872 AT 4AM 01/08/17 IN 116 HRS
this one, 5 days out, says it will max at 4.2 feet at 4am in the morning of 1/8, here are the next 17 forecasts... which one is wrong? why are they different?
205 PM PLT TUE JAN 03 2017
(POHC1) MAX 5.7 1,960 AT 4AM 01/08/17 IN 110 HRS
819 AM PLT WED JAN 04 2017
(POHC1) MAX 23.7 24,700 AT 5PM 01/08/17 IN 105 HRS
855 AM PLT WED JAN 04 2017
(POHC1) MAX 23.7 24,700 AT 5PM 01/08/17 IN 104 HRS
218 PM PLT WED JAN 04 2017
(POHC1) MAX 23.1 24,400 AT 5PM 01/08/17 IN 99 HRS
841 AM PLT THU JAN 05 2017
(POHC1) MAX 15.5 15,600 AT 4PM 01/08/17 IN 79 HRS
219 PM PLT THU JAN 05 2017
(POHC1) MAX 15.9 16,200 AT 5PM 01/08/17 IN 75 HRS
834 AM PLT FRI JAN 06 2017
(POHC1) MAX 16.2 16,700 AT 5PM 01/08/17 IN 56 HRS
953 AM PLT FRI JAN 06 2017
(POHC1) MAX 16.2 16,700 AT 5PM 01/08/17 IN 55 HRS
150 PM PLT FRI JAN 06 2017
(POHC1) MAX 16.1 16,600 AT 5PM 01/08/17 IN 51 HRS
836 AM PLT SAT JAN 07 2017
(POHC1) MAX 17.6 19,000 AT 4PM 01/08/17 IN 31 HRS
158 PM PLT SAT JAN 07 2017
(POHC1) MAX 18.4 20,000 AT 4PM 01/08/17 IN 26 HRS
824 PM PLT SAT JAN 07 2017
(POHC1) MAX 19.7 21,600 AT 4PM 01/08/17 IN 20 HRS*
204 AM PLT SUN JAN 08 2017
(POHC1) MAX 15.8 16,100 AT 5PM 01/08/17 IN 15 HRS*
253 AM PLT SUN JAN 08 2017
(POHC1) MAX 15.8 16,100 AT 5PM 01/08/17 IN 14 HRS*
852 AM PLT SUN JAN 08 2017
(POHC1) MAX 12.1 9,580 AT 10PM 01/08/17 IN 13 HRS*
204 PM PLT SUN JAN 08 2017
(POHC1) MAX 11.8 9,050 AT 10PM 01/08/17 IN 8 HRS*
813 PM PLT SUN JAN 08 2017
(POHC1) MAX 12.4 9,990 AT 12AM 01/09/17 IN 4 HRS*
306 AM PLT MON JAN 09 2017
(POHC1) MAX 13.1 11,100 AT 4AM 01/09/17 IN 1 HRS*
914 AM PLT MON JAN 09 2017
(POHC1) MAX 11.7 8,960 AT CURRENT TIME *
216 PM PLT MON JAN 09 2017
(POHC1) MAX 10.0 6,600 AT CURRENT TIME
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mcreel
climber
Barcelona
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Jan 11, 2017 - 10:43pm PT
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From that sequence, it looks like the model is fairly nonlinear, so that "small" changes in inputs can have a "big" change in outputs. That seems reasonable for a model of runoff/drainage. Stuff like this is hard to forecast accurately. Reporting confidence is important, from a scientific perspective. A forecast of 23 is not very different from one of 17, if the standard error is 5. The need to make people act to prepare to avoid extreme consequences of events that have a non-negligible probability of occurring may be a reason that reported forecasts might de-emphasize the uncertainty.
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Ed Hartouni
Trad climber
Livermore, CA
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Jan 11, 2017 - 10:56pm PT
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here is the sequence in time, with EdBannister's prediction...
the NOAA prediction includes changes due to various weather factors... and is trying to predict how much rain will fall over some area at some time...
I ask EdBannister again, what is wrong?
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