Llano River Bridge Collapse in Texas 21

[JAE]

Video of the collapse due to high river:

https://www.youtube.com/watch?v=EY45z_vXbSQ

Before:

After:

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[Spartan5]

A local curious "statistical anomaly":

 

[BridgeSmith]

I said it'spossible rainfall patterns are changing in the region, but it's also possible that the recent heavier rains are just an anomaly, like having a flipped coin come up heads 6 times out of 8.

Someday Spartan5, perhaps you'll grasp the difference between accepting the obvious that change does happen, and accepting the unsupported assertion that a particular change is taking place in a particular region at a particular time. I'm rapidly losing hope, though.

Again, nice graphs, but completely irrelevant.

 

[BridgeSmith]

As far as the changes to the rainfall event frequency update by NOAA for the region, there remains the possibly that the historical record simply does not go back far enough to accurately predict the return periods for those events. According to the report in your link, they are "redefining the amount of rainfall it takes to qualify as a 100-year or 1000-year event." Not surprising that they need to redefine them, considering they only have 200 years worth of data to work with (again, only a hundred or so of which is reliable). The change is just as easily the result of an inadequate data set as an actual change in the regional climate (which, of course, I never denied was a possibility, just didn't accept as fact).

 

[BridgeSmith]

To circle back somewhat closer to the actual subject, regardless whether the higher rainfall represents an anomaly or shift in the climate, the changes to the NOAA Atlas 14 occurred well after the subject bridge was designed and built. Therefore, it should not be assumed to an inadequate design because it was not adequate for this flood event.

 

[Spartan5]

I said it'spossible rainfall patterns are changing in the region, but it's also possible that the recent heavier rains are just an anomaly, like having a flipped coin come up heads 6 times out of 8.

Someday Spartan5, perhaps you'll grasp the difference between accepting the obvious that change does happen, and accepting the unsupported assertion that a particular change is taking place in a particular region at a particular time. I'm rapidly losing hope, though

HotRod... you're welcome to believe whatever you want. In a world in which anything can be dismissed by boiling it down to a coin toss exercise, some really fascinating things must be possible. I envy the power of your imagination.

I accept the science though. The science that has been supported by detailed and comprehensive statistical analysis conducted by experts in their field, and published for all to validate and comment on.

Are you really trying to tell all of us that what I posted is an unsupported assertion: In Austin, for example, 100-year rainfall amounts for 24 hours increased as much as three inches up to 13 inches. 100-year estimates around Houston increased from 13 inches to 18 inches and values previously classified as 100-year events are now much more frequent 25-year events. Do you really profess to know more about statistics than those who completed that work?

 

[BridgeSmith]

"Do you really profess to know more about statistics than those who completed that work?"

I didn't see a claim in that statement that the climate in Austin, Texas has changed, only that the statistical probabilities related to rainfall amounts have been revised based recent data. If 50 years from now, they haven't seen rainfall events as significant as those occurring recently, the probabilities will likely be revised back down. As I tried to explain to you several times, regardless of what the rainfall amounts average out to be, or how those averages get revised in the future, it is not necessarily evidence of a change in the climate. It could very well be due to the historical record being inadequate to accurately establish the probabilities. The sample size is just to small to really know.

 

[Spartan5]

"Prove it."

Like evolution. Or the age of the planet.

I surrender.

 

[BridgeSmith]

Nice parting shot, Spartan5. Make up a quote, attribute it to me, and then run away. Very professional.

 

[IRstuff]

I wasn't talking about the strength scale; I was referring to the lack of tools available to accurately measure the strength of the hurricanes that did occur during those earlier years.

I pointed out that the same basic instrument for the measurement of air speed was invented in 15th century, and the Beaufort system used anemometers for windspeed measurements in 1850, so it's been nearly 170 years of reasonably accurate windspeed measurement.

"...since the hurricanes they're talking about are more apropos for latitudes where apples are common fruit, as opposed to tropical hurricanes, where oranges are more common."

When did I assert that my statement only applied to tropical hurricanes? For that matter, when did you?"

You referenced a slew of articles, which, I pointed out, are talking about mid-latitude storms, and not tropical storms.

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert!

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[jgailla]

https://xkcd.com/258/

 

[BridgeSmith]

"I pointed out that the same basic instrument for the measurement of air speed was invented in 15th century..."

Are you really going try to argue that a few anemometers can measure the intensity and size of a hurricane as accurately as a satellite? BTW, does your graph include only the intensity of the hurricanes as they made landfall? I'll bet most or all of the few anemometers that were around in the 1800's were land based.

"You referenced a slew of articles, which, I pointed out, are talking about mid-latitude storms, and not tropical storms."

Ok, fine. Since when is the count of tropical hurricanes more valid in determining the overall trend than mid-latitude hurricanes?

 

[thebard3]

https://xkcd.com/258/

Also known as 'cognitive dissonance'. Nobody wins the argument, they just become more sure of their view.

Brad Waybright

It's all okay as long as it's okay.

 

[Mongrel]

Really, the biggest problem with the climate change "debate" is exactly this. Climate change has been latched onto as a political vehicle, with a good chance of leveraging it for cash (see: carbon trading, for example).
Now, it's practically become a cult religion. The members point to all the papers printed agreeing with them, because nobody dares to disagree anymore. They get shouted down and driven away, from what I've seen. Anyone who dares to even ask what happened to the disastrous climate events predicted in the past, that we're supposed to be suffering from now, gets the same treatment.
Personally, I feel we do need to clean up our act - but not because of whether or not the climate might change. Just because of general pollution levels, less crap in the air, water, and land, and less waste. It seems like the responsible and efficient thing to do in any case.
Perhaps instead of threatening people with hell, we should be working on improving society and education so that they will willingly work towards a better future?

 

[BridgeSmith]

Here is the statement from the World Meteorological Organization on climate change and tropical cyclones. Before anyone reads the statement and calls this a flip flop or a capitulation, let's remind ourselves of the original statement made by IRstuff that I took issue with: "This type of storm, and the hurricanes, continue to get more frequent and more severe."

Now let's see what the first point of the WMO statement says about that: "1. Though there is evidence both for and against the existence of a detectable anthropogenic signal in the tropical cyclone climate record to date, no firm conclusion can be made on this point."

 

[RVAmeche]

I wonder what other scientific phenomenon/discoveries had similar turmoil in history or if they would've if information/disinformatoin was so rapidly shared then. Galileo is probably the easiest example to point to. I wonder if people claimed Ampere and Faraday were full of it.

It'd sure be a shame if we spent all this time and effort to try to reduce pollution and human waste for nothing. Maybe after another 100 years of data the "debate" will finally be settled. Based off the ongoing arguments against evolution it doesn't seem likely.

 

[BridgeSmith]

Don't worry, RVAmeche, when the effects of the solar minimum are fully felt, the global warming alarmists will once again become global cooling alarmists, though the solution will be the same - more power and money to the government.

 

[Spartan5]

I find it hard to buy into the rhetoric that storms are worse today then they have been historically. I try to pay attention to historical data of similar events when a storm occurs. During many of these media touted "worst ever" weather events I see that similar weather events have also occurred 60-200 years ago. For example, Florence really wasn't an abnormal hurricane only possible today. There have been a number of other recorded hurricanes as strong or stronger that have hit that area dating back to the last 200 years.

We have recently built-up many areas more that in the past. So there are more structures and people for these storms to impact. This just makes the impact and devastation of the humans and infrastructure worse then what has occurred historically. But, that impact is often confused with it being a worse storm event.

East Pacific - I believe there have been 2 category 5 hurricanes this year. Apparently 1994 had 3 stronger ones. Just saying...

Only sharing because I saw that the remnants of Willa were will likely impact the East Coast as well this weekend (and bring more misery to Texas as well). And you mentioned that you try to pay attention to this stuff.

1994 had three Cat 5 hurricanes in the E. Pacific. Maybe you've missed the last two Cat 5s in 2018 because they've both happened in the last couple of weeks. But we've now tied the 1994 and 2002 record for Cat 5s with three, and surpassed the 2015 Record of seven Cat 4 or greater by three (now at ten on the season). That makes 2018 to be the most intense (Accumulated Cyclone Energy) in nearly 50 years of reliable measurements (since 1971). Just saying...

1994:

2018:

 

[cvg]

interesting tidbit for those who question the “1-percent AEP flood” criteria

https://pubs.usgs.gov/gip/106/pdf/100-year-flood-handout-042610.pdf[/URL]]The 1-percent AEP flood has a 1-percent chance of occurring in any given year; however, during the span of a 30-year mortgage, a home in the 1-percent AEP (100-year) floodplain has a 26-percent chance of being flooded at least once during those 30 years! The value of 26 percent is based on probability theory that accounts for each of the 30 years having a 1-percent chance of flooding.

 

[Spartan5]

interesting tidbit for those who question the “1-percent AEP flood” criteria

The formula is for the % probability of at least 1 occurrence in a particular number of years is: 100(1-(1-1/x)^n)
where x is the annual return period of the event (e.g. "100"-year storm) and n is the number of years for which you are assessing it could occur.

 

[ATSE]

cvg - I'm 90% sure that this is just a simple binomial probability.
Success rate = p = 0.01 (forgive the term; success just means that event happens)
n = number of trials = 30 (one per year)
Number of successes = 1 or more
Likelihood = 26% for 1 or more (agrees with USGS, which is nice)
Likelihood = 22% for exactly 1 event
Likelihood = 74% for exactly 0 events

100-year event as a standard isn't so high after all, considering the damage levels.

Statistically, you could have (10) "100-year event" storms in 10 years or zero in 100 years. When many events occur back to back in the same year or consequential years, consider that your physical model might be wrong. Or you're just unlikely, like when New Zealand had a long string of destructive earthquakes 2010 thru 2011. Even if you consider that as a single event, that's extremely rare in the modern era.
Back to the original post.
Extremely rare events sometimes occur. Sometimes multiple extremely rare events occur back to back. If spending 5% extra gets you 30% more robustness to the unknown, I don't need any more math to convince me that's a good bargain. Just need someone to scratch up that extra 5%.
If using the term climate changes gets me that extra 5%, then sign me up.