Hurricane Harvey Insane Metrics, Non-AGW Aspects and AGW Aspects

[WadeDanielSmith]

Here are some stats on Harvey so far, which might not be widely known.

Max Potential Intensity Predictor: 200-225MPH 1-minute sustained.

Even after the insane amount of upwelling associated with the storm near the Texas coast, the Thermodynamic Max Potential Intensity predictor in the western Gulf of Mexico remains above Category 5. Much of the remainder of the Gulf remains at 200 to 225 mph predictor levels.


Max Real Intensity: 131mph 1-minute sustained, or bare minimum for Category 4 classification.
Most Measured Rainfall in an Official NWS/NOAA gauge: Over 34 inches and climbing.
Max Radar indicated isolated rainfall: 60 inches on two different radars (for the same location near Houston).

Max VIL at landfall: 210kg/m^2
Max VIL Yesterday: 245kg/m^2
Max VIL today: 195kg/m^2

For comparison:
Highest VIL I've seen in an EF5 Tornado on radar: 120kg/m^2
Highest VIL I've seen on radar from a Category 5 hurricane: 71kg/m^2*
* I didn't have access to this information for 2005 Atlantic season nor the infamous Hurricane Mitch in Honduras.


Closest Analogs for max total rainfall in the Atlantic Basin:
Hurricane Wilma, Cancun Mexico.
Mitch, Honduras.
Amelia, Texas (Previous U.S. record holder).

Worst inland flooding in U.S. history NOT associated with a Tsunami or Volcano (but this is much more widespread than the Lahars from flash melting of glaciers at Mt. St. Helens, though NOT as locally geologically catastrophic.

Record River levels 10 to 11 feet above the previous record level, which was either Hurricane Amelia or Tropical Storm Allison, depending on which river basin you are looking at.


So what caused this?

Normal Cycles involved:
Perfect Gulf Stream Loop Eddy cut-off scenario.
Perfect Neutral ENSO cycle year.
Zero shear during the "explosive intensification" cycle.
Max Thermodynamic Potential Intensity predictor 200 to 225mph.

Man-Induced contribution:

Concrete and Asphault claim:
Not really. This only effects absorption levels by about 1 inch worth of rain in an entire flood scenario, which is quite frankly insignificant to the totals we've actually seen. You wouldnt' even notice the difference.

Man-Made Global Warming:
Based on the long-term average convection/precipitation enhancement from above average temperatures of SST, this probably has made somewhere between a 7% difference and a 10% difference in rainfall totals. However, the previous record would have been smashed even without man-made Global Warming. There is the matter than the mathematics of Hurricanes can sometimes be "chaotic" in which case approximations of the effects of a SST change may not translate 1 to 1 with reality. This will require probably several years of super-computer analysis to figure out exactly what the real "Global Warming Enhancement" percentage really is...

Post-Season super-computer analysis for both statistical models and deterministic models can run for weeks or months, while predictive models for forecasting only run for 6 to 12 hours, sometimes less. It took around 10 years for super-computer models to fully understand Hurricane Wilma at max intensity, which is now known, based on those models, to have been a 223mph 1-minute sustained hurricane, though the NHC has left the "official" intensity at 185mph. This gets complicated, but in the case of Wilma, the computer model discovered a third "Bifurcation Point" in Cyclone formation, which contributed to it's incredible maximum intensity over water. The incredible 215mph 1-minute sustained E. Pac Hurricane, Patricia, likely behaves the same way.

However, some of these models may eventually prove useful in studying Harvey's insanely well-maintained convection levels; Three consecutive days of radar indicated VIL at or above 190kg/m^2 is completely outrageous. Hopefully, since the computers are so powerful now, and we have 12 years software development research since then, we will have a head-start on eventually understanding Harvey better. However the predictive/forecasting models were actually not designed to handle this scenario, and some of them experienced "Breaking the Map" problems during the forecast of maximum rainfall potential. This will need to be corrected for future storm seasons.

Thanks,
If you have any questions, or if I'm required to post references, forgive me, I'll look for them if requests are made, but the only thing here that might require a reference is the Wilma calculation, I think...I'll look it up.

[ghoti]

Wade everything you post here and on the arctic sea ice blogs says nothing is caused by global warming. According to you global warming has no impact on anything.

Fox news agrees with you. Climate scientists disagree.

[Jim Hunt]

Climate scientists disagree.

See this  sequence of "tweets" from Gavin Schmidt:

https://twitter.com/ClimateOfGavin/status/902317222986743809

Things that are happening now naturally generate questions about precip intensity, hurricane genesis, intensification, statistics etc

These questions might not have easy or straightforward answers. Indeed they are often at the cutting edge of current research.

[BenB]

Wade, where do you get your figures for the concrete/asphalt claim? It appears to contradict what the USGS says here: https://pubs.usgs.gov/fs/fs07603/

For a 100-year storm, they give a 10 to 250 percent increase in peak discharge. This increase is smaller than for more moderate storms, but still significant.

[Daniel B.]

Wade, where do you get your figures for the concrete/asphalt claim? It appears to contradict what the USGS says here: https://pubs.usgs.gov/fs/fs07603/

For a 100-year storm, they give a 10 to 250 percent increase in peak discharge. This increase is smaller than for more moderate storms, but still significant.

A brief history of the flood history.

https://www.hcfcd.org/flooding-floodplains/harris-countys-flooding-history/

http://www.houstonchronicle.com/local/bayou-city-history/article/Houston-s-devastating-flood-of-1935-6293100.php

Is this a 100-year storm?  Hardly!  While rainfall totals are sure to break some records, the flooding is not all that unique.  Buffalo Bayou, in downtown Houston, has reached 38 feet (flood level is 28).  During tropical storm Allison in 2001, it crested at 40 feet.  During the 1929 flood, it crested at 42 feet.  During the great flood of 1935, it crested at 49!  Houston has a long history of catastrophic flooding.

Houston also has a history of deluges.  The city received 24 inches of rain in 24 hours during Harvey.  The 24-hour rainfall total still belongs to tropical storm Claudette in 1979, when it dumped 42 inches of rain on Alvin, TX (just south of Houston).  Yes, this storm will rank as one of the most destructive.  However, people tend to exaggerate recent events compared to past episodes, somehow forgetting the past. 

[Archimid]

Daniel B. I'm quiet sure that floods have always happened in the Houston area. However, I would expect that as the world warmed the frequency of high intensity(and cost) floods increased. As the world warms even more this will happen more frequent. Does any one have a good (recent) link that   quantifies the frequency of these types of events? Anything before 2014 is probably outdated, but I doubt much exist that includes the last 3 years.

[BenB]

Daniel, I'm not quite sure what your point is, or at least how it is relavent to my point. Do you mean that it wasn't a 100-year storm? I guess that depends on which metric you are using. But if you had looked at my link, and my comment, you would see that the effect of urbanisation is greater the less exceptionial the storm. So for a 50-year storm, and even more so for a 10-year storm, the effect of concreting/asphalting over the landscape is greater than for a 100-year storm. So if it wasn't a 100-year storm, it only strengthens my point.

[Jim Pettit]

Is this a 100-year storm?  Hardly!  While rainfall totals are sure to break some records, the flooding is not all that unique.  Buffalo Bayou, in downtown Houston, has reached 38 feet (flood level is 28).  During tropical storm Allison in 2001, it crested at 40 feet.  During the 1929 flood, it crested at 42 feet.  During the great flood of 1935, it crested at 49!  Houston has a long history of catastrophic flooding.

Houston also has a history of deluges.  The city received 24 inches of rain in 24 hours during Harvey.  The 24-hour rainfall total still belongs to tropical storm Claudette in 1979, when it dumped 42 inches of rain on Alvin, TX (just south of Houston).  Yes, this storm will rank as one of the most destructive.  However, people tend to exaggerate recent events compared to past episodes, somehow forgetting the past.

This ongoing catastrophe isn't a 100-year storm; it's a 500-year storm, the third one the Houston area has experienced in the past five years. (Keep in mind that calling a deluge a 500-year flood doesn't mean it will only happen once every 500 years; it means the odds of it happening in any given year are 1-in-500.)

At any rate, the fact is that Harvey isn't just the worst rainstorm in Houston history--at this point, Allison is far back in the rearview mirror, along with all other previous Houston deluges. No, it's also likely the biggest flood-producing storm this nation has ever seen.

FWIW, that 45 inches Alvin received from Claudette was confined to a tiny area; Harvey has dumped far more water than Claudette over a much larger area.

FWIW II: preliminary estimates put Harvey's total damage--that is, direct and indirect financial impacts--at $150-$200 billion. In other words, possibly approaching a doubling of Katrina's impact.

Bottom line: Harvey is one for the record books. No exaggeration required.

[wili]

At what point can we just call Dan B the denialist that he seems to be and boot him off. I thought there was kind of a policy against denialist trolls around here, one of the things that makes this place refreshing.

(Queue Dan's whining response claiming we don't want to hear 'all sides' and other predictable denialist tripe...)

[WadeDanielSmith]

Wade everything you post here and on the arctic sea ice blogs says nothing is caused by global warming. According to you global warming has no impact on anything.

Fox news agrees with you. Climate scientists disagree.

Uh, you are a damned liar.

Piss off, loser.

I actually know AGW is going to be worse than you think, guy, I can do the calculations by hand on a piece of paper. Believe it or not, I'm smart enough to do that without a half- billion dollar super computer at my disposal, unlike the fools you actually pay to do this.

Piss off guy. You suck at this.


Believe me, I still beat Jeff masters at this HALF the time, and he hates my guts because of it, because I put him to shame on some hurricane forecasts a few seasons ago.

Piss off.

Ask him about it. I called 60 inches rainfall totalsy when NHC and TWC were still hung up around 20 inches and didn't yet believe what they were seeing.

I wrote letters to Masters and Henson telling them to amp up the language.

ASK HIM ABOUT. IT.

He hates my guts, but this is the truth.

[wili]

hmmmm, yet another troll??

[WadeDanielSmith]

No, fool.

I'm warning you.

You think this is bad?

You have't seen jack shit from AGW just yet.

This isn't even remotely beginning just yet.

You think this is bad?

IN 150 to 200 years none of the coastal cities you worry abou twill have so much as a high rise building left standing above sea level.

This is nothing kid.

And if that isn't bad enough, the cold phase of the Milankovich Cycle is going to erase it all in a few hundreed generations anyway.

You go ahead and whine about AGW all you want. Hey, it's twice as bad as you think it is.

However, the truth is, the next Glacial Maximum is gonig to kill 95% of all humans on the planet anyway, about 50,000 to 60,000 years from now.

Figure that one out.

you just think AGW is bad for life, but the ordinary Glacial Maximum is the number 1 killer of all life on this planet.

[crandles]

So you think
https://www.carbonbrief.org/human-emissions-will-delay-next-ice-age-by-50000-years-study-says

is wrong?

[WadeDanielSmith]

By the way, thermal maximums in solar cycles lag the flux maximum by about 10% to 15% of the entire cycle.

Daytime his is around 2 to 3pm.
Hottest month for a hemisphere is usually 30 days or so behind the longest day of the year.
etc.

The Milankovich Cycle's solar input maximized about 7000 years ago, however, the hottest NATURAL year in the cycle is actually around 11,600 years behind the solar maximum of the cycle. However, the rate of warming has slowed down a lot, and will continue to slow down.

This means the next "Neutral" phase fo this Milankovich Cycle does not start for about another 4600 years.

Have fun explaining that one to them, because this is not even remotely getting started just yet. Not by one one hundredth of how bad it will get over the next several centuries and millennia.

And THAT is a blessing compared to the coldest phase of the cycle. Trust me, mile thick ice frozen as solid as steel over half each of three of the continents tends to mostly life-wipe them every 116,000 years.

[WadeDanielSmith]

The Earth only needs about 50 to 100 years to fully reverse man-made emissions, because if you actually paid attention to the annual down cycle of the keeling curve, the plant life absorbs around 12ppm per year worth of CO2, but humans currently produce around 14 to 15ppm per year, making a 2ppm or 3ppm excess.

You greatly deceive yourself, kid. Just look at the raw data.

I promise you the next Glacial maximum kills 90% to 95% of all humans on the planet when it happens.

[Daniel B.]

Daniel B. I'm quiet sure that floods have always happened in the Houston area. However, I would expect that as the world warmed the frequency of high intensity(and cost) floods increased. As the world warms even more this will happen more frequent. Does any one have a good (recent) link that   quantifies the frequency of these types of events? Anything before 2014 is probably outdated, but I doubt much exist that includes the last 3 years.

A warming world would most likely increase the potential for flooding as rainfall will increase.  The metrics for flood history is difficult to ascertain as water management will skew the result heavily.  Houston did just so after the devastating 1929 and 1935 floods.  Dams and levees tend to diminish flooding frequency, as they can hold back the waters during most rainfalls.  The floods that do occur, tend to be worse.

[WadeDanielSmith]

Let me explain to you something about the Geologic Record.

There are more than "Five Great Mass Extinctions" in the Geological record. Ask your professor.

They mainly only talk about five because humans liki round numbers, and they don't have time to talk about 100 mass extinctions...and no, the Asteroid that killed the dinosaurs is actually not even one of the five worst mass extinctions. The only reason they talk about that one si because the dinosaurs were the largest known group of land animals to have ever lived.

there are extinctions in the Ordivician and Hadean that make that look like an insignificant blip by comparison, including a million years long super-plume eruption which blocked the Sun out forever, but had part of the ocean at an open boil, and turned almost the whole ocean into sulfuric acid, way, way more destructive than the Carbonic acid from the Permian. The problem with this, which is probably by far the real worst extinction, is that it destroyed most of its own evidence. The Geologists know this happened, but many of the life forms that were destroyed in it simply dissolved before they hit bottom, leaving few or no traces. But they actually have that wrong, the Permian Mass extinction is the SECOND worst mass extinction, since about a billion years ago anyway. This dropped the pH of the entire globe by several full points, but jellyfish, fish, arthropods, algae, bacteria, diatoms, worms/bivalves, etc, all survived it, somehow, and ironically, they did not even need to evolve to survive it.

That's some real Gologic History.

Man-made acidification is pretyt minimal in comparison.

The sea butterflies will survive it, and the reason I know they will survive it is because they've survived something 10,000 times worse than anything you can imagine before.

[Daniel B.]

Daniel, I'm not quite sure what your point is, or at least how it is relavent to my point. Do you mean that it wasn't a 100-year storm? I guess that depends on which metric you are using. But if you had looked at my link, and my comment, you would see that the effect of urbanisation is greater the less exceptionial the storm. So for a 50-year storm, and even more so for a 10-year storm, the effect of concreting/asphalting over the landscape is greater than for a 100-year storm. So if it wasn't a 100-year storm, it only strengthens my point.

Ben, I am not questioning the effects of urbanization, as these tend to channel more water into fewer outlets.  This is effective for most rainfall events.  However, they can handle only so much.  When they become inundated, the flooding effects are compounded. 

Regarding a 100-yr storm, I think that term is way overused.  The Houston area has experienced several of these during the past century.  Therefore, how can we call it a 100-yr storm?  Some people try to outdo others by calling it a 500-year or 1000-year storm, as if we have records going that far back to know.  If those are the odds of it occurring, then someone must be poor at statistics for them to occur much more frequently. 

Yes, this storm is extraordinary.  Was it worse that Allison, Claudette, or event the great Galveston Hurricane?  Well, that depends on ones perspective.  All four of these belong in the same category.  However, Harvey should be used as a reminder for urban planners (and others) about the power of nature.  When the 1929 flood hit Houston, the planners did nothing.  After the 1935 flood, the people were up in arms, and the current system was built.  However, Houston was a much smaller city then, and perhaps, a new system should be established.  Harvey and other recent storms have shown that. 

It seems some people want to deny this aspect of the issue, and pretend it does not exist.  Get rid of him!  Boot him!  He's a troll!  We do not want to hear about it!  Sorry to burst your bubbles.

[crandles]

The Earth only needs about 50 to 100 years to fully reverse man-made emissions, because if you actually paid attention to the annual down cycle of the keeling curve, the plant life absorbs around 12ppm per year worth of CO2, but humans currently produce around 14 to 15ppm per year, making a 2ppm or 3ppm excess.

You greatly deceive yourself, kid. Just look at the raw data.

I promise you the next Glacial maximum kills 90% to 95% of all humans on the planet when it happens.

I thought Ghoti was wrong to call you as a denialist troll.

However, you are not doing yourself any good with an attitude of I know it all.

Just because I think Ghoti was wrong does not mean I call him a liar, I think that was an honest mistake.

Just because the biosphere is absorbing 12ppm doesn't mean it will continue to do so until back to preindustrial levels. Baring major new experimentation with carbon cycle, about 25% will remain in the atmosphere declining at only a very slow rate due to rock weathering is the current scientific opinion. That could be wrong but given your know-it-all attitude I would definitely prefer to believe the scientific opinion than what you tell me.

Not nice to wrongly be called a denialist troll, but your response isn't good either. How about a bit more humility?

[Avalonian]

WDS, your understanding of mass extinctions is rather iffy (being generous). You claim a Hadean mass extinction, when there is as yet no firm evidence of life before the Late Heavy Bombardment, and even if the suggestive evidence of life at 4.1 Bya is verified, we have no knowledge of how much lived among pore spaces beneath the surface. In short, we haven't a clue what percentage of living species was wiped out at that time, if it existed.

Likewise, the Snowball Earth interval is peculiar in that a huge extinction loss would be anticipated, but very little decrease in diversity is seen for either the Sturtian or Marinoan glaciations. This may be due to the organisation of ecology at this time, and the absence of 'complex' organisms leading to a much more ecologically stable biosphere.

In the Phanerozoic, there are indeed many 'extinction events' but they fall onto a continuum of severity. Many affected just one group of organisms (graptolites were particularly prone to catastrophes, for example), and for most of those we don't have any real understanding of what caused them. 

There are five 'mass extinctions' that were more severe than the others (affecting more taxa in a relatively short interval), but they vary from the brief and catastrophic (e.g. the end-Cretaceous asteroid, which nearly killed off the dinosaurs) to tectonic-scale changes that affected ecosystems over a million years or more. Among the smallest extinctions that we see an obvious cause for are the glacial-interglacial cycles. Some megafauna was stuffed, admittedly (although that may have been largely human-related), but insects simply moved; we can trace rapid changes in terrestrial beetle faunas, for example. In the tropics, nothing much changed.

Of course, human society would be severely affected (including a substantial population reduction) if there was a switch back to glacial conditions due to Milankovitch cyclicity, but I personally find that very unlikely due to the greenhouse forcing overriding it. A mass extinction, though? Unlikely. It's never happened before (except at the end-Ordovician, which was an altogether more spectacular affair).

The main problem is that you're claiming all sorts of special knowledge, when it's clear you don't actually understand the evidence you're using to support it. People in that position don't have the right to be belligerant.

[Neven]

I had to ban Wade, as such a start doesn't promise things will go well further down the line. FYI.

[Avalonian]

Thanks Neven. I thought it was probably heading that way! 

[CraigsIsland]

The main problem is that you're claiming all sorts of special knowledge, when it's clear you don't actually understand the evidence you're using to support it. People in that position don't have the right to be belligerant.

Agreed.

WDS, it's good that you're trying to highlight the statistics of Hurricane Harvey, but your tone of writing and other "points" need to be more "coherent" to a well-formed argument. You should be trying to build consensus, not trying to sound like a madman(woman). I'm trying not to be offensive, but really, I think some of us fellow posters might be dissuaded and put off by your writing.

Harvey stats are insane, but 99% of people aren't going to believe that this one event will lead to a mass-extinction event.

If anything, work on your writing by enrolling in a community college class. Keep posting, but stick to small bites of evidence and clear hypothesis and testing.

[CraigsIsland]

I had to ban Wade, as such a start doesn't promise things will go well further down the line. FYI.

And there's the hammer

[Agric]

  Firm but fair, Neven. WDS's posts were making me feel a tad nauseous with their splattergun cherry picking of mostly extraneous factoids. Besides which s/he said:

I promise you the next Glacial maximum kills 90% to 95% of all humans on the planet when it happens.

I dislike such promises and fear we humans have insufficient patience to wait that long 

[Shared Humanity]

Just visited this thread. That's 15 minutes of my life I will never get back.

[Jim Pettit]

From the Washington Post:

Harvey marks the most extreme rain event in U.S. history

The rain from Harvey is in a class of its own. The storm has unloaded over 50 inches of rain east of Houston, the greatest amount ever recorded in the Lower 48 states from a single storm. And it’s still raining.

John Nielsen-Gammon, Texas state climatologist, said a rain gauge in Mont Belvieu, about 40 miles east of Houston, had registered 51.1 inches of rain through early Tuesday afternoon. This total exceeds the previous record of 48 inches set during tropical cyclone Amelia in Medina, Texas in 1978.

All rainfalls totals from this storm are still preliminary and require review. But, if verified, this amount breaks not only the Texas state rainfall record but also the record for the remaining Lower 48 states.

So, no: NOT like other storms.

[wili]

"I had to ban Wade" Thanks, Nev.

[Ned W]

Just because the biosphere is absorbing 12ppm doesn't mean it will continue to do so until back to preindustrial levels. Baring major new experimentation with carbon cycle, about 25% will remain in the atmosphere declining at only a very slow rate due to rock weathering is the current scientific opinion.

No kidding.  The "next glacial maximum" that Wade is afraid of is not likely to occur any time in the next half million years, thanks to all that CO2 we're emitting:

Carbon cycle models indicate that ∼25% of CO2 from fossil fuel combustion will remain in the atmosphere for thousands of years, and ∼7% will remain beyond one hundred thousand years (Archer, 2005). We predict that a carbon release from fossil fuels or methane hydrate deposits of 5000 Gton C could prevent glaciation for the next 500,000 years, until after not one but two 400 kyr cycle eccentricity minima. The duration and intensity of the projected interglacial period are longer than have been seen in the last 2.6 million years.

[M]oderate anthropogenic cumulative CO2 emissions of 1,000 to 1,500 gigatonnes of carbon will postpone the next glacial inception by at least 100,000 years.

I'm not worried that any humans will be killed in the next glacial maximum because I figure our distant descendants a half million years from now will be able to deal with that when the time comes.  There are more immediate problems to deal with.

[Archimid]

Not to mention that the glacial minimum will happen over thousands of years. That is not even noticeable over human lifetimes. Is not even noticeable over many generations.

[logicmanPatrick]

Re: had to ban Wade

quite apart from posting foul language in the wrong thread, s/he lost points by posting acronyms without explanation.

Wikipedia is the site I had to look this one up in.
VIL Vertically integrated liquid.

Glad to post here, where nobody gets banned for abuse of prepositions.   

[gerontocrat]

... s/he lost points by posting acronyms without explanation.

Wikipedia is the site I had to look this one up in.
VIL Vertically integrated liquid.

I am off to the pub later. I shall ask for a pint of VIL, and endure the abuse from the spectacularly attractive lady behind the bar.

[Red]

I had to ban Wade, as such a start doesn't promise things will go well further down the line. FYI.

+1 little knowledge can be a dangerous thing.

[Sigmetnow]

Gently sarcastic, quotable opinion piece from the LA Times.

Harvey should be a warning to Trump that climate change is a global threat

If Trump himself were to consult the experts — such as, you know, climate scientists — he would learn that global warming is real. He’d also learn that although warming did not cause Hurricane Harvey, it certainly makes such storms stronger, more unpredictable and quicker to intensify. Experts — there’s that word again — say that warmer air temperatures mean more evaporation of moisture from the seas to the skies, and thus more rainfall from storms. Warmer seas — including the Gulf of Mexico — intensify storms, from their size to their wind speeds, and amplify storm surges. (In southeast Texas, the flat geography allows a surging Gulf to intrude farther inland.) Another wrinkle, according to atmospheric scientist Michael E. Mann: Climate change modeling suggests that human-propelled global warming could lead to weaker prevailing winds and a jet stream tracking father north. And that appears to have been what led Harvey to park over southeast Texas and dump more than 40 inches of water in places rather than spreading the rain (and pain) around or drifting back out over the Gulf. ...

http://www.latimes.com/opinion/editorials/la-ed-harvey-global-warming-trump-flood-20170830-story,amp.html

[Ned W]

I had to ban Wade, as such a start doesn't promise things will go well further down the line. FYI.

Totally justified, but I kind of regret not hearing more about this:

...super-plume eruption which blocked the Sun out forever...

Huh.  The Sun was blocked out forever.  Why has nobody noticed this?  How is my garden feeding me without photosynthesis?   The mind reels.

[jai mitchell]

The Earth only needs about 50 to 100 years to fully reverse man-made emissions, because if you actually paid attention to the annual down cycle of the keeling curve, the plant life absorbs around 12ppm per year worth of CO2, but humans currently produce around 14 to 15ppm per year, making a 2ppm or 3ppm excess.

You greatly deceive yourself, kid. Just look at the raw data.

I promise you the next Glacial maximum kills 90% to 95% of all humans on the planet when it happens.

I thought Ghoti was wrong to call you as a denialist troll.

However, you are not doing yourself any good with an attitude of I know it all.

Just because I think Ghoti was wrong does not mean I call him a liar, I think that was an honest mistake.

Just because the biosphere is absorbing 12ppm doesn't mean it will continue to do so until back to preindustrial levels. Baring major new experimentation with carbon cycle, about 25% will remain in the atmosphere declining at only a very slow rate due to rock weathering is the current scientific opinion. That could be wrong but given your know-it-all attitude I would definitely prefer to believe the scientific opinion than what you tell me.

Not nice to wrongly be called a denialist troll, but your response isn't good either. How about a bit more humility?

the biosphere also EMITS about 10 ppm per year in the Northern Hemisphere Fall season.  So the very pretext of the statement about 12 ppm captured per year is not a long-term benefit but rather a seasonal cycle of leaf growth and death in the northern hemisphere (as well as temperature cycles).

[jai mitchell]

The Milankovich Cycle's solar input maximized about 7000 years ago

Max 60'N insolation was achieved around 12,000 years ago, it went down after that.

[Daniel B.]

I had to ban Wade, as such a start doesn't promise things will go well further down the line. FYI.

Totally justified, but I kind of regret not hearing more about this:

...super-plume eruption which blocked the Sun out forever...

Huh.  The Sun was blocked out forever.  Why has nobody noticed this?  How is my garden feeding me without photosynthesis?   The mind reels.

Missed that the first time.  Perhaps, because I did not bother to read all that he wrote.  Perhaps he was just using that terminology from this book.

https://i.gr-assets.com/images/S/compressed.photo.goodreads.com/books/1498790295i/35554810._UY630_SR1200,630_.jpg


https://images.gr-assets.com/books/1498790295l/35554810.jpg

[Michael Hauber]

Wade, where do you get your figures for the concrete/asphalt claim? It appears to contradict what the USGS says here: https://pubs.usgs.gov/fs/fs07603/

For a 100-year storm, they give a 10 to 250 percent increase in peak discharge. This increase is smaller than for more moderate storms, but still significant.

Not sure where I've seen it, but I've seen a figure of 2 inches of rainfall (50mm in my language) can be absorbed by earth before significant water flows.  Personal experience watching heavy rain events and resulting stream gauge rises suggests this is reasonable with minor rises visible often near 50mm or so of rainfall.  For short term rain (<1hr) the rain can fall faster than the earth can absorb it and water flows despite soil saturation not being reached.  I'd be pretty confident that for asphalt etc the amount of rain absorbed before flow is close enough to 0 not to matter.

It seems quite reasonable that in a suburban area 50% of the land area is covered by concrete/roofing and other impervious surface, resulting in urbanisation being the equivelant of increasing rain amounts by about 1 inch in an event such as Harvey.

The research you linked to looks like creek flooding.  In creek flooding the characteristic time frames are much shorter for a peak flood.  So a 1 in a hundred year flood in a small creek might be 4 inches in 1 hours.  Being a short time frame bare earth might only absorb half this amount, so the difference is half an inch, and urbanisation is a change of 12.5% in amount of water flow.  Then for a large river basin the 1 in a hundred year event might by 30 inches in 24 hours and the same 1 inch urbanisation impact is only 3%.  For a small creek flash flood event the fact that concrete/asphalt may allow water to run faster may also matter more than for a larger slower moving river flood event.

[sidd]

i dunno where to put this:

https://www.cnbc.com/2017/08/30/arkema-ceo-no-way-to-potentially-stop-an-explosion.html

thing is  gonna blow.

sidd

[miki]

I promise you the next Glacial maximum kills 90% to 95% of all humans on the planet when it happens.

I may recall you, that we made it through the last glaciation. I sincerely doubt we'll perform that well in the hotter world ahed. And that's all I have to say about that.

[greatdying2]

Man-Made Global Warming:
Based on the long-term average convection/precipitation enhancement from above average temperatures of SST, this probably has made somewhere between a 7% difference and a 10% difference in rainfall totals. However, the previous record would have been smashed even without man-made Global Warming. There is the matter than the mathematics of Hurricanes can sometimes be "chaotic" in which case approximations of the effects of a SST change may not translate 1 to 1 with reality. This will require probably several years of super-computer analysis to figure out exactly what the real "Global Warming Enhancement" percentage really is...

That's not how it works. Means and extremes are completely different things -- that's a critical lesson to learn about climate change. (After all, if everywhere just warmed up 2 C, who would really care...) And computers just crunch numbers, they don't magically learn unknown physics. There is currently no way to know how much AGW contributed to any particular storm because we don't understand the climate system well enough. However, models have long predicted a trend of large increases in maximum storm intensity, which is just what is now coming to pass.

It is quite possible that Harvey would never have even occurred if not for AGW, or if it did, may have had no noticeable impact on the US.

Expect more and worse. I wonder how many "1000-year" events it will take before certain people start to pull their heads out of their ... sand boxes.

The hurricane churned up water 100 or even 200 meters below the surface, said Trenberth, but this water was still warm—meaning that the storm could keep growing and strengthening. “Harvey was not in a good position to intensify the way it did, because it was so close to land. It’s amazing it was able to do that.”

The human contribution can be up to 30 percent or so of the total rainfall coming out of the storm

-- Kevin Trenberth, Senior Scientist at the U.S. National Center for Atmospheric Research
https://www.theatlantic.com/science/archive/2017/08/did-climate-change-intensify-hurricane-harvey/538158/

[BenB]

Michael, I think there are various problems with your argument:

The 2 inches before water flows across the surface isn't really relevant - the point is how much water will be absorbed over the course of the storm. Water will continue to be absorbed after you get surface flooding, albeit at a slower rate, until all of the soil above the bedrock is completely saturated. This is not the same as the very top layer of the soil being saturated, which will cause initial surface flooding. The amount absorbed depends (as does your 2 inch figure) on local conditions, but may be much greater than 2 inches. Either way, Wade needed to justify this figure, rather than pull it out of thin air.

Creeks vs. average flood level: Some of the figures in the USGS article relate to peak discharge of creeks, but they also refer generally to the effect of urbanisation on flooding. Besides, what causes problem fooding is not average water levels across the duration of the storm, but peak levels in specific places at specific times. Here peak discharge is absolutely relevant.

Difference between small/large creeks and small/large flood events: this is dealt with in the article, and in my post - the impact of urbanisation is much bigger for shorter-lasting, smaller flash flooding events, but still non-trivial in bigger, longer-lasting events. According to the USGS. 

[crandles]

To what extent, if any, would people agree with the statement

If landfalls appear to be decreasing, then hurricanes should not be used as an added reason for needing more action to deal with GW.

[oren]

To what extent, if any, would people agree with the statement

If landfalls appear to be decreasing, then hurricanes should not be used as an added reason for needing more action to deal with GW.

If landfalls appear to be decreasing (are they?), but the intensity of landfalling hurricanes is increasing, then hurricanes should be used as an added reason for needing more action to deal with GW.

[Neven]

Added reasons not needed. 

[crandles]

If landfalls appear to be decreasing (are they?), but the intensity of landfalling hurricanes is increasing, then hurricanes should be used as an added reason for needing more action to deal with GW.

Good question. I think US landfalls may (debatably possibly depending on timeframe) have become less frequent, but I am pretty clueless about worldwide stats.

Greater intensity but less frequent: Is that a valid reason? Comparing thousands of deaths in Bangladesh and other less developed regions to about 40? even if that increases quite a bit, the lesson seems to be industrialise as fast as you can to save deaths. If you don't want to talk deaths and instead damage, then there being more infrastructure and human wealth to damage seems the prime reason for Harvey being expensive. Yes if there is more intensity you might expect more damage but is it rising faster than the more industrialised becomes more resilient effect?

If the argument is difficult to make perhaps we should stick to to Neven's 'Added reasons not needed'?

[Archimid]

I  prefer 10 cat 1 or smaller storms a year over 1 cat 5 a year. Our infrastructure is built to withstand cat 1 and less pretty well.  However our infrastructure did not evolve to withstand Cat 3, 4 and 5 since they were so rare during the  20th century.

If there are less storms, it is expected that we get less landfalls, but if there are more  cat 3,4 and 5 storms it is more likely that one of those make landfall. The difference in destruction between cat 5's and 1's is not linear. Cat 5 are orders of magnitude more expensive than cat 1's.

[gerontocrat]

Last year it rained in Louisiana - a lot. It was simply a depression sucking vast amounts of warm wet air from the ocean. Floods are more destructive than wind - hence that you can often get wind insurance but not flood insurance.

If it ain't one then 'tis the other.