CNN is calling Hurricane Patricia “The Most Dangerous Hurricane in History.” Another news outlet showed a picture of the hurricane and pointed out “The Enormous Size of Hurricane Patricia.”
Both of these are wrong. Size matters with hurricanes. A category 5 hurricane that is twice as large as another category 5 hurricane is “more dangerous” all else being equal, and by “all else” I mean things like exactly where it hits, how fast it is moving, exactly how strong it is (category 5 includes a very wide range of wind speeds because it is the highest category). Hurricane Patricia is not huge.
Patricia is very dangerous, has a very low pressure center and very strong winds, both being at or near record breaking levels. But the hurricane is small. Here’s a VERY rough size comparison between two of the well known and very large hurricanes that I just slapped together:
The larger hurricanes will cover more area with their dangerous winds, may have a more extensive storm tide, and will very likely bring a lot more rain inland. Patricia will do very bad things where it makes landfall, which is actually happening as I write this, but that area will be smaller than a Katrina like hurricane. And it will bring a fair amount of water inland, but not nearly as much as a monster like Haiyan would have.
So yes, take Patricia seriously. But I expect to see a lot of yammering after the fact, from certain factions, about how everyone was being very alarmist about Patricia when in the end it was not a Katrina.
So let it be understood. Patricia is no Katrina. But it is impressive in its own way.
It is time to discuss, once again, the falsehood known as “Hurricane Landfall.”
A hurricane is a whopping big thing. A hurricane can be bigger than some states. The physical region across which a hurricane is potentially deadly and damaging is very large, many tens of miles across, sometimes a couple of hundred miles across. The danger zones are often organized like this:
The central storm surge. A central region may have a strong storm surge caused by the low pressure of the storm. This may be dozens of miles wide, but the area of effect is determined as much by the shape of the coastline the hurricane is landing on as by the hurricane itself.
The Right Punch. To the right of the central storm surge area is a region where the counter-clockwise rotating storm bearing down on the coast and hinterland will have very strong winds combined with very low pressure to increase the storm surge even more.
The storm surge caused by the low pressure system and the right punch can be a very wide area, and it can affect a coastal region for a long period of time, as the “surge” itself maybe several miles “deep.” If a hurricane is moving slowly, if the winds are strong and the pressure low, and if tides are already high and coastal flooding is already underway because of hurricane caused rain that came through for several hours before the surge arrives, this flooding can be extensive.
In some cases, the initial flooding may be very bad but the secondary flow of flood waters can be worse. If a hurricane storm surge and rain-related floods fill up the lagoons behind barrier islands, and at the same time the outlets get clogged by debris pushed up by high waves, that flooding can break open the barrier beaches in new locations, which may or my not be underneath settlements, major roads, etc. (This was, by the way, the theme of the famous book “Condominium” by John D. MacDonald which had a lot of inaccurate or outdated science but still stands as a classic “Disaster” book.)
So to review so far, around the middle of the hurricane is very low pressure, and to the right of this middle are very strong winds (and low pressure) that can cause a big flood that can first run over the land and flood stuff, then run back to the ocean and do even worse damage. Well within this area is the “eye” of the storm. The area of storm surge is much, much larger than the eye.
Spin-off Tornadoes. The big giant hurricane may cause the formation of many small tornadoes which will essentially act as very intense ambassadors of the passing cyclone. The tornadoes actually form as a function off the weakening, or generally messing up, of the organized cyclonic hurricane. They tend to form in advance of “Landfall” by as much as two days, but are most common as the hurricane’s right front quadrant is over land, and occur over a very large area. (They can also occur long after the Hurricane is downgraded to a tropical storm and is mostly on land, days after “landfall.”)
Hurricane Winds. Around this area of storm surge is a region of hurricane- or near hurricane-force winds which, especially if the hurricane is moving slowly, can buffet an area for hours and hours of time. This is like one of those nasty thunderstorms with the ‘straight line winds” coming through and knocking down a couple of trees, but for several hours. The area of these winds is typically measurable in the hundreds of miles in all directions.
Flooding Rains. Usually, over a larger area than this wind zone there will be bands of rain falling. The region over which sufficient rain to cause flooding may fall is hundreds of miles in any one direction. Flooding may start long before the hurricane force winds reach the coast. After the hurricane is way inland and is no longer called a hurricane, it can still cause major flooding. If you live, say, in Virginia or Connecticut, don’t think the hurricane has missed you just because it hits the Gulf Coast. You may be in for some major flooding in a week or so.
The Landfall Fallacy. Now, there is this thing about scientists, even meteorologists. When dealing with time-based phenomena, they need to know when something starts and when it ends, so they can do things like measure when on average certain things start, how long on average they last, etc. Therefore, there has to be an agreed upon point in time when a hurricane starts to exist (this is when the winds reach a certain strength and the cyclonic storm reaches a certain degree of organization, all of which is actually kinda hard to measure but they do it anyway). There is also an agreed upon point at which the hurricane “hits land” … known as landfall. This is when the eye of the hurricane, which is usually still visible on satellite views, on radar, as well as on the ground, crosses the shoreline. That is the arbitrarily decided on moment when scientists say the hurricane is at a certain point in its life cycle.
This does not. Repeat, not. NOT. mean that a hurricane “hits land” or “arrives” or “becomes a problem” or “starts to do damage” on “landfall.” No. The hurricane arrived hours before landfall! The outer bands that brought the beginnings of flooding rain came way before. The occasional tornado spun off by a hurricane may have already done in a neighborhood hours before. The highly damaging winds arrived long ago. The storm surge may have even started to chew up cities, towns, and industrial areas along the coast before the eye wall crosses landward, depending on all sorts of different factors. Hell, it is actually possible for a hurricane to totally mess up a coastal region then move back out to sea with the eye never crossing the coast. No landfall, but big problems. Landfall is not arrival.
The reason I mention this is that the “landfall fallacy” was one of the two Great Stupidosities that happened in relation to Hurricane Katrina, the anniversary of which is coming soon, and I fear that this fallacy remains in place (or has made a comeback) as we approach the visitation of Hurricane Isaac, now entering the Gulf of Mexico. (The other fallacy is that Katrina did not breach the dikes in NOLA, that they were breached by a flood. Which must have happened at the same time as the hurricane. But really was the hurricane… yes, you can imagine that these two Stupidosities, both perpetuated by a combination of ill intentioned politicians and not very well trained weather reporters and other journalists, are related.)
In a way, Hurricane Isaac is already affecting the Gulf coast because people are reacting to it! But really, it may be hours before “landfall” when we see our first serious flooding, wind damage, tornadoes, and all that, wherever Isaac ends up going. The area across which it will affect things will be much, much broader than the spot it makes landfall. When Katrina hit, Mississippi really took it in the neck. Huge areas of coastal Mississippi were wiped out. But, since “landfall” was in New Orleans, it didn’t make a lot of sense to report much of that in the early days of that disaster.
The hurricane hits where it hits, and it is a Big Giant Thing. Isaac may very well hit BOTH Mississippi and New Orleans, and a bit of Florida, just like Katrina did.
When will the madness end? When the Republicans dry up and blow away, of course.
In the Republican response to Obama’s State of the Union 2.0 address, by Bobby Jindal, governer of Louisiana, we heard this:
“Instead of monitoring volcanoes, what Congress should be monitoring is the eruption of spending in Washington, D.C.,”
The reason why volcanoes have been picked out of some speech writer’s anal sphincter zone is because they erupt and they wanted the metaphor. Or because Jindal believes he has no volcanoes in his state (but he would be wrong) or because of some other rhetorical reason. This is the same exact device as the bear paternity test complaint we heard spewing forth from the Hypocrite McCain and the Moron Palin during the campaign.
Do Republicans (or moderates who don’t have a kneejerk anti-Republican reflex) also feel like he’s talking to the nation as though we were all kindergarteners? I was flabbergasted, but I don’t know how to properly account for my rather strong political biases here.
“Why does Bobby Jindal think monitoring volcanoes is a bad thing for the government to be doing?” Nick Baumann writes in Mother Jones. “There doesn’t seem to be any immediate way for private enterprise to profit from monitoring volcanoes (maybe selling volcano insurance?), but there is obviously a huge public benefit from making sure volcanoes are monitored: warning people if a volcano is going to erupt. Isn’t that obvious?”
OK, so clearly the Republicans are mean spirited knowledge-free hypocrites and Jindal is therefore a great spokesperson (or should I say spokesman) for them. And Maria and Sciam are right. But everyone is missing the true irony here.
The true irony is this: Remember New Orleans? Remember Katrina? Scientific research on disaster prediction predicted Katrina and its effects on New Orleans perfectly. PERFECTLY I SAY!!!! But those predictions were ignored (and continue to be ingnored).
But scientific monitoring does not always get ignored. The roads are laid out in many places with consideration for evacuation in the case of certain events. As Maria pointed out, large numbers of lives and dollars were saved from the effects of the eruption of Mt. Pinatubo … which was a (say it with me now) a volcano … Because. Of. Scientific. Monitoring. And so on. Katrina is seen as an immeasurably large disaster of public policy because the clear warnings from the scientific research were ignored. Had they not been ignored, we would not be talking about this.
Teh Irony, then, is that the biggest disaster happened in the most third world of the states because of the boobs that run that place, and Bobby Jindal is Head Boob. And he is telling us what we need to do regarding scientific monitoring of potential natural disasters.
The metaphors! They are everywhere!
The fox is giving us a lesson on how to close the chicken coop. The farmer who left the barn door open is telling us about how to take care of your horses. The pot is explaining to the kettle how to clean off the soot. Chicken little is giving us a lesson on framing. The little Dutch boy is taking piano lessons. The Republican is telling us how to manage scientific priorities.
Oh, no, wait, that last one is not a metaphor. It is a TRAGEDY!!!!