Guest essay by Paul Homewood
With special thanks to John Fuller and Agar012 (and Dr. Ryan Maue for review)
Now we have had a few days to reflect on the terrible events of last week, we can start to piece together some of the facts.
First of all, as it is the thing that really matters above all, fatalities. The good news, if it can be termed that, is that the death toll is likely to be around 2000 to 2500, according to the Philippine President. This is much less than the 10,000 originally feared to have died.
As far as the storm itself was concerned, the official statistics from the Philippine Met Agency, PAGASA, remain the same as those issued at the time. The table below compares these with the original satellite estimates put out by the Joint Typhoon Warning Centre, JTWC, and that were subsequently used by the media around the world to claim that Yolanda was the “strongest storm ever”.
| PAGASA | JTWC | |
| Sustained Wind Speed mph | 147 | 195 |
| Gust mph | 171 | 235 |
http://www.ndrrmc.gov.ph/attachments/article/1124/Update%20SWB%20No.6%20re%20TY%20YOLANDA%205AM.pdf
http://www.webcitation.org/6KyWsFio5
http://www.bbc.co.uk/news/world-asia-24878801
As far as sustained wind speeds are concerned, the PAGASA numbers are based on 10-minute averages, whilst the JTWC are on 1-minute averages, so the latter are always likely to be higher. Is it possible then to draw any conclusions?
According to NOAA NHC hurricane expert, Chris Landsea,
“One complication with the use of the 1 min averaging time for the standard for sustained wind in the Atlantic and Northeast Pacific tropical cyclone basins (where the United States has the official World Meteorological Organization tropical cyclone advisory responsibilities) is that in most of the rest of the world, a 10 min averaging time is utilized for “sustained wind”. While one can utilize a simple ratio to convert from peak 10 min wind to peak 1 min wind (roughly 12% higher for the latter), such systematic differences to make interbasin comparison of tropical cyclones around the world problematic. “
So on this rule of thumb,adding 12% to the PAGASA number would increase it to 164 mph, on 1-minute averages.
Jeff Masters also mentions that other studies suggest a ratio of 1.14, which would give a figure of 167 mph. He also points out that the Japanese Meteorological Agency estimate 145 mph, using satellite based 10-minute averages, therefore backing up the PAGASA version.
There is still, therefore, a big gap between JTWC and the others. A clue to this difference is given by Masters:
Haiyan’s strongest winds occurred on the south shore of Samar Island and the city of Guiuan (population 47,000), where the super typhoon initially made landfall with 1-minute average winds estimated at 195 mph. This estimate came from the Joint Typhoon Warning Center, and was based on satellite measurements. We have no ground level or hurricane hunter measurements to verify this estimate. Typhoon and hurricane maximum wind speed estimates are only valid for over water exposure, and winds over land are typically reduced by about 15%, due to friction. This would put Haiyan’s winds at 165 mph over land areas on the south shore of Samar Island.
So how does all this compare with earlier hurricanes and is there any justification for the “strongest ever” claims.
Hurricane Camille in 1969 is generally accepted as the strongest in recent decades. NOAA describe the wind speeds:
The actual maximum sustained winds will never be known, as the hurricane destroyed all the wind-recording instruments in the landfall area. The estimates at the coast are near 200 mph.
The “Atlantic Hurricane Season of 1969”, published at the time offers more detail:
Note that 180 knots = 207 mph, and 175 knots = 202 mph.
Quite simply Yolanda and Camille cannot be seriously compared with each other.
It is probably also worth taking note of these two statements.
Mr. Paciente [a forecaster with the Philippine government’s national weather agency] stated:
Before the typhoon made landfall, some international forecasters were estimating wind speeds at 195 m.p.h., which would have meant the storm would hit with winds among the strongest recorded. But local forecasters later disputed those estimates. “Some of the reports of wind speeds were exaggerated,”
The Philippine weather agency measured winds on the eastern edge of the country at about 150 m.p.h., he said, with some tracking stations recording speeds as low as 100 m.p.h.
Roger Edson, the science and operations officer at the United States National Weather Service in Guam said
195 m.p.h. winds would put the storm “off the charts,” but he acknowledged that satellite estimates require further study on the ground to determine if they were accurate.
Wind Gusts
As well as the discrepancies in sustained wind speed, there is also a big gap in the claimed top gusts. Chris Landsea also has a useful rule of thumb:
Gusts are a few seconds (3-5 s) wind peak. Typically in a hurricane environment, the value of the maximum 3 second gust over a 1 minute period is on the order of 1.3 times (or 30% higher than) than the 1 min sustained wind.
So, assuming 164 mph sustained winds, we would expect gusts of 213 mph. Whereas JTWC estimated 235 mph, the figure officially recorded by PAGASA was only 171 mph, which suggests the sustained speeds may have been slightly lower than we have assumed.
Atmospheric Pressure
The atmospheric pressure of Yolanda was 895 hPa. Within just the Western Pacific Basin, there have been 20 storms with lower pressure since these figures began to be reliably collected about 60 years ago. The lowest pressure recorded was 870 hPa, with Typhoon Tip in 1979.
Together with ties, typhoons with Yolanda’s atmospheric pressure or less can be expected every couple of years in the Western Pacific. Fortunately the vast majority of these never see land, or do so only after significant weakening.
Storm Surge
Both CNN and the BBC talk about 40 to 50 feet storm surges , yet the official Philippine body responsible for these matters, NOAH, using JMA models, on 7th November forecast about 5 meters or less for the day after when the storm hit land.
Once again, it appears that some media reports have been wildly overhyped.
Historical Trends
PAGASA show a couple of graphs plotting the number of tropical cyclones from 1948 to 2004. There seems to be little in the way of trends either way.
http://kidlat.pagasa.dost.gov.ph/cab/main.htm
There is a fear that although typhoons are not becoming more frequent, they may be getting more intense. However, given the lack of accurate data from even just a few decades ago, it is difficult to see how any real conclusions can be made.
Summary
It seems reasonable to conclude that Yolanda was a Category 5 storm, i.e. that 1-minute wind speeds were at least 157 mph. However, it was clearly a much less powerful storm than Camille, and arguably many others in recent history.
It is, fortunately, a rare occurrence for storms of Yolanda’s strength to cross land, but sometimes it does happen.
The sensationalist and over-hyped reporting of much of the media immediately after the tragedy was, in my view, utterly disgraceful. Perhaps in future, they might care to check the facts first.
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David Wells says
November 14, 2013 at 1:56 am
“Get over it and move on at their birth rate they will make up the deficit within days.”
If you are interested in facts rather than prejudice then it is worth taking the test at http://www.bbc.co.uk/news/magazine-24836917 and see how accurate your current knowledge is and watching the program.
Philippine population has risen from 60 million to 90 million enough said. Think Richard LH you have missed the main thrust of my text, if the planet lost a few billion humans so what, the fact remains and it is not that human reproduction maybe slowing down overall its that right now there are too many of us and wildlife is being pushed out and China, Indonesia, Malaysia just love grinding up animals bits and using them for medicine have you seen exactly how fishermen in this area rip of sharks fins and through the defined shark back in still alive to suffer a slow death. These guys will kill and eat anything and have no concerns whatsoever about anything other than themselves we should not waste our time blubbing over a few thousand and 16,000 at Fukushima still trumps a few thousand at the Philippines does it not. I am up with the program its all a load of cobblers the world is what it is and the real issue is that too many people on both sides and right down the middle of the climate debate are making money out of something about which we can do nothing whatsoever its about time the facile argument about what causes this is that is irrelevant because it cannot be changed. Once fossil fuel is extinct then its over in any case there is no replacement.
Daniel Vogler
Has anybody explained the 858 millibar recorded on:
http://www.ssd.noaa.gov/PS/TROP/DATA/2013/tdata/wpac/31W.html
It shows 858 mb with 170knots.
The 895 mb figure comes from the Japanese Met Agency.
http://metofficenews.wordpress.com/2013/11/08/typhoon-haiyan-makes-landfall-over-the-philippines/
NOAA’s figures appear all over the place ranging from your 858 to this one at 885 mb.
http://www.ssd.noaa.gov/PS/TROP/DATA/2013/adt/text/31W-list.txt
Martin
Homewood said in an earlier post:
Terrible though this storm was, it only ranks as a Category 4 storm
Now he is saying:
It seems reasonable to conclude that Yolanda was a Category 5 storm
Wonder what else he’s gone and got wrong!
As more information comes through, I am quite happy to update previous statements.I just hope the MSM do the same.
Excellent post. Thank you.
Here’s a link to JTWC observation/warning 8th nov:
http://web.archive.org/web/20131109013931/http://www.usno.navy.mil/NOOC/nmfc-ph/RSS/jtwc/warnings/wp3113web.txt
TYPHOON 31W (HAIYAN) WARNING NR 023 WARNING POSITION:
081800Z — NEAR 12.4N 118.1E
MOVEMENT PAST SIX HOURS – 285 DEGREES AT 23 KTS
POSITION ACCURATE TO WITHIN 045 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS – 125 KT, GUSTS 150 KT
and one to original warnings for 7th-12th nov
http://biasedbbc.org/wp-content/uploads/2013/11/2048x2048_11072153_haiyanfinal.png
PBS Newshour last night had a reporter call it “the strongest storm ever recorded”. No data will change what they want to believe.
The people who write the news want nothing more than to use superlatives. It has always been that way and will likely stay that way for ever. This has nothing to do with any agenda, other than the agenda to use superlatives. They work very hard at including words like: worst, most, deadliest, costliest, biggest, smallest, best, fastest, longest, saddest, darkest, and so on. Negative superlatives are always prefered over positive superlatives. The warmests are experts at handing the media negative superlatives, so they get the coverage!
The media does not have an agenda to promote CAGW, other than their desire to use superlatives. For CAGW skeptics to get traction with the media, they cannot talk about how ‘normal’ climate will be in the future. That is simply not news. We will have to figure out a way to ‘sell’ the story with superlatives.
Paul Homewood said: “Quite simply Yolanda and Camille cannot be seriously compared with each other.”
Gee, just in the prior paragraph regarding Camille you note that “The actual maximum sustained winds will never be known, as the hurricane destroyed all the wind-recording instruments in the landfall area. The estimates at the coast are near 200 mph.”
Estimates (not measurements) at the coast, not over landfall, were near 200 mph. And we don’t know whether that was for 1 minute, 10 minutes – apparently you just assume the latter since that serves your premise. You then quote a journalist – you know, the same people who at the start of your post are excoriated for being inaccurate. I guess that accusation does not apply to historical journalism? The story says that the US Navy detected speeds of 180 knots (207 mph) 100 miles offshore. Yolanda reached 195 mph at landfall, and it’s not comparable to a storm that reached 200 mph offshore? I’m absolutely baffled at your logic.
As far as the fatalities, that number is already up to 4460, with many areas yet to report due to inaccessibility. As expected, the Philippines President is downplaying the figures as this tragedy has put huge pressure on his administration.
Chris
The 200 mph estimates for Camille come straight from NOAA. These are based on 1-min averages, and not 10 min.
http://en.wikipedia.org/wiki/Hurricane_Camille
http://www.nhc.noaa.gov/outreach/history/#camille
(If you had thought first before making this comment, you would have realised if they were 10-min averages, the 1-min figure would be even higher!)
If you had bothered to check out the “Atlantic Hurricane Season of 1969” review, you would have realised it was not a “journalist’s story” but a scientific paper from the National Hurricane Centre.
The estimates of 175 knots within a few hundred yards of the coast (this means landward by the way unless the houses were out at sea), were made on the same sort of basis we use for tornadoes – i.e damage to structures.
This may not be perfect, but it is probably as good as we will get.
And then you compound your errors by stating that Yolanda reached 195 mph at landfall. It did not, it only reached 147 mph based on 10-min averages, or likely in the region of 165 mph on 1-min averages.
As for the fatality figures, they were up to date estimates yesterday, when this post was published. No doubt the figures will change as time goes on.
But at least you managed to spell our names right!
Chris writes:
As far as the fatalities…
AP withdraws report of 4,460 dead in Philippines typhoon
Can I point out that there is a unintended positive consequence that happens as a result of the sensationalist and over-hyped reporting, it gets the worlds attention and encourages a faster response for disaster relief.
‘The sensationalist and over-hyped reporting of much of the media immediately after the tragedy was, in my view, utterly disgraceful. Perhaps in future, they might care to check the facts first’
No they won’t. No money in facts.
regards.
ps. my comments are not edited by Maurice Strong. ( Terrorista Illuminista )
I am slightly amazed that so many people point to Hurricane Camille in 1969, but not Hurricane Allen in 1980.
Wiki:
sustained winds of 190 mph
From http://www.hpc.ncep.noaa.gov/research/txhur.pdf:
Paul, wow a lot of work put in. But you should really explain that that change of mind about Category 4. here and on the last page It’s always OK to admit errors and this really was an exceptional circumstance to be able to say PAGASA 10min average speed of 147mph making it a Category 4, can reasonably be guessed as being 167mph on 1min average so making it a Category 5.
– But as regards those 195mph and 235mph gust speed : Extraordinary claims require extraordinary evidence. So I think we can’t assume that the 195mph peak landfall speed estimate by JTWC can be called fact. Also note that JTWC estimate is for less than 3 hours before landfall , it would be different if it had given an estimate for similar speeds 6 or 13 hours earlier.
I note that the Wikipedia page NOW has a large section about climate change COP19 etc and has also been locked. They no longer make claims about the biggest ever ..now calling it one of the biggest.
I believe the way it’s written is misleading, like claiming the the 195mph as landfall speed, but only citing Weatherunderground as a source. Similar weak links etc. And the Talk seems to be full of people desperate to get the climate change spin angle put in.
Considering that the upshot of Kyoto, and other policies to reduce atmospheric CO2 effectively removes the opportunity of countries like the Philippines having access to cheap energy, and are relegating third world countries to “high energy cost” poverty, I find it utterly repulsive that alarmists seem to revel in the death toll as some measure of just how correct their argument is ….
It is POVERTY that killed so many … does anyone think so many would have been killed if the same winds had hit Florida ?
On a similar issue, when are the BBC going to call people out on constant falsehoods such as “The strongest typhoon ever to hit land” … the answer, regrettably is never, and that is why WUWT is SO important
Unless satellite images are vastly misleading…I’d say Haiyan, at initial landfall (a bit south of Guiuan), was AT LEAST as strong as Typhoon Megi. Remember that Typhoon Megi had aircraft measurements of 885mb and 190mph 1-minute winds (145mph 10-min winds) at the time of the photo in this comparison:
http://cbsboston.files.wordpress.com/2013/11/comparison.png
My heart goes out to all those affected.
Paul,
I read through all of your links, and did not see 1 minute intervals of averages for the actual wind speed for Camille. The references say estimated wind speed. Here’s a quote from a detailed post-Camille study, co-authored by Roger Pielke – “There were no records of winds near the eye of the storm, but estimates ranged up to 190 mph.” That’s not 1 minute intervals, which you imply in your rebuttal, but an estimate based on structural damage.
To my point about Yolanda reaching 195 mph at landfall, yes, it did. I quote from Dr. Jeff Masters of Wunderground – “Three hours before landfall, the Joint Typhoon Warning Center (JTWC) assessed Haiyan’s sustained winds at 195 mph, gusting to 235 mph, making it the 4th strongest tropical cyclone in world history. Satellite loops show that Haiyan weakened only slightly, if at all, in the two hours after JTWC’s advisory, so the super typhoon likely made landfall with winds near 195 mph. The next JTWC intensity estimate, for 00Z UTC November 8, about three hours after landfall, put the top winds at 185 mph. Averaging together these estimates gives a strength of 190 mph an hour after landfall. Thus, Haiyan had winds of 190 – 195 mph at landfall, making it the strongest tropical cyclone on record to make landfall in world history. The previous record was held by the Atlantic’s Hurricane Camille of 1969, which made landfall in Mississippi with 190 mph winds.”
http://www.wunderground.com/blog/JeffMasters/article.html?entrynum=2578
Clearly based on this, Haiyan/Yolanda is comparable to Camille, contrary to your assertion.
As to the number of deaths, I agree the total will vary, and unfortunately, is just going to rise over time – today I’ve seen figures of 4400 and 3600, with the caveat that many remote places have not even been contacted yet. It’s quite clear that whatever figures are stated now are quite premature and thus not a good gauge of what the ultimate total will be.
At the end of your post, you state: “The sensationalist and over-hyped reporting of much of the media immediately after the tragedy was, in my view, utterly disgraceful. Perhaps in future, they might care to check the facts first.”
In your rush to discredit the media reporting, you’ve gone to the other extreme – under-hyping the severity of the storm and the deaths. Perhaps in the future you should check your facts first.
Chris
The link to NOAA states
The actual maximum sustained winds will never be known, as the hurricane destroyed all the wind-recording instruments in the landfall area. The estimates at the coast are near 200 mph.
This is backed up by the damage reports, as I pointed out.
http://www.nhc.noaa.gov/outreach/history/#camille
Of course, we will never know the actual speeds, but the figures I have quoted are widely accepted as realistic.
As for the JTWC numbers, these are not supported by the PAGASA measurements. This really is the essence of the post. You may have missed the original post on this.
http://notalotofpeopleknowthat.wordpress.com/2013/11/09/super-typhoon-yolanda/
And the PAGASA advisory at the time of landfall is below.
http://www.ndrrmc.gov.ph/attachments/article/1124/Advisory%20SWB%20No.6%20re%20TY%20YOLANDA%205AM.pdf
Of course, it may turn out that the Philippines Met Agency were wrong, but my main objection was that the MSM were jumping all over the sensationalist bandwagon, even though the PAGASA data was already published contradicting it. Surely they should have checked it out first?
Paul
Paul,
I don’t have an issue agreeing with the Camille numbers, as long as its acknowledged that those are estimates, and not instrument or radar based.
Given that, then it seems to me that for Yolanda, if we are comparing apples to apples, the focus should be on 1 minute, not 10 minute figures – for 2 reasons. The first is that a visual damage assessment (ie what was done for Camille) will be a function of the damage peak winds do, not long term (10 minute) sustained winds. Second, if the starting point of the conversation is on the damage storms do to lives and property, it seems to me that winds being sustained for 1 minute is sufficient to damage buildings – I’d be doubtful that much more damage occurs between the 1 minute mark and the 10 minute mark.
As to the gap between PAGASA and JWTC data, it may be that the fast moving speed of the storm made the usual 1min to 10 min multipliers incorrect. Or it could be that the PAGASA instruments at the location of the storm’s landfall at Guiuan were destroyed – http://www.claimsjournal.com/news/international/2013/11/11/239775.htm
If JWTC were known for having sloppy data, I could understand questioning the use of their figures. But from what I’ve seen, they are well regarded. As to PAGASA and the Philippines government, we already have a police chief who was sacked because he estimated fatalities of 10,000 (which, if true, makes the government look bad), and a President who clearly substantially understated the death tolls.
I fully acknowledge that the press, in general, often sensationalize calamities. But in this case I think their figures will be proven correct.
PBS has relentlessly pedaled the AGW propaganda . I only see their Newshour by chance when I happen to be at my parent’s house at that time. And it seems like every time they have some propaganda piece on climate, the last being on the storm in the Philippines. And, as usual, they had the views of two guests, but on this topic, both on the same side, i.e. Kevin Trenberth of Climategate fame and Jeff Masters of the Weather Underground.
More of us need to voice complaints to the PBS ombudsman. http://www.pbs.org/ombudsman/feedback.html