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Things I dislike: Awaiting looming disaster.
Be safe, New Orleans. If you get evac orders, please get out. Overtopped levees are a big deal & you've got a confluence of events lining up just wrong in the near future.
Be safe, New Orleans. If you get evac orders, please get out. Overtopped levees are a big deal & you've got a confluence of events lining up just wrong in the near future.
Water is easy to underestimate. "Turn around, don't drown" is trite but key life-safety messaging.
Ankle-deep flowing water can knock an adult down.
Tire-deep flowing water can wash away a car.
Even standing water can be full of nastiness.
Ankle-deep flowing water can knock an adult down.
Tire-deep flowing water can wash away a car.
Even standing water can be full of nastiness.
Storms are all about heat + water.
Warmer oceans means we get more storms, that storms are stronger, and that storms build up from nothing to nightmare faster.
Warmer oceans means we get more storms, that storms are stronger, and that storms build up from nothing to nightmare faster.
Risk changes over time, both with the physics of the natural hazards (more, bigger storms) & with increased vulnerability (more people & structures).
The levees were built for an era long past.
The levees were built for an era long past.
New Orleans has a lot of practice at floods. But it's not normally so many ways for the water to rise all at the same time.
This is a "Shit happens." scenario that emergency managers think about, plan for, and hope doesn't actually happen.
This is a "Shit happens." scenario that emergency managers think about, plan for, and hope doesn't actually happen.
New Orleans is one of those cities where humans have accidentally made things so much worse in an effort to make them better.
To start with, it's sinking. Literally.
This is subsidence 2009-2012 with stars at Katrina level breaks
Learn more & 📸: jpl.nasa.gov/news/news.php?…
To start with, it's sinking. Literally.
This is subsidence 2009-2012 with stars at Katrina level breaks
Learn more & 📸: jpl.nasa.gov/news/news.php?…
It's completely normal for river deltas to sink over time. All those saturated sediments compact over time.
But in an unmanaged system, fresh sediment is always getting deposited by the river (especially from upstream floods carrying floodplain sediments downstream.)
But in an unmanaged system, fresh sediment is always getting deposited by the river (especially from upstream floods carrying floodplain sediments downstream.)
In an unmanaged system, rivers meander & shift over time. Unmanaged rivers also flood, overfilling & spilling into the surrounding floodplains.
The Mississippi used to do that, but now we control it to minimize floods.
Learn more:
earthobservatory.nasa.gov/images/6887/mi…
blogs.loc.gov/maps/2016/06/t…
The Mississippi used to do that, but now we control it to minimize floods.
Learn more:
earthobservatory.nasa.gov/images/6887/mi…
blogs.loc.gov/maps/2016/06/t…
When we locked the Mississippi (& other rivers) in place & reduced flooding, we cut off sediment supply.
When we locked the river mouth in place & started dredging for ports, we cut off delta sediment supply.
It's a managed system now.
When we locked the river mouth in place & started dredging for ports, we cut off delta sediment supply.
It's a managed system now.
It's completely normal for coastlines to get hit by storms & floods.
Unmanaged environments like mangroves, sand dunes, marshes & bayous are REALLY GOOD at dynamically absorbing storm impacts, flooding, & sediment flux.
But we've stripped them from many coastlines.
Unmanaged environments like mangroves, sand dunes, marshes & bayous are REALLY GOOD at dynamically absorbing storm impacts, flooding, & sediment flux.
But we've stripped them from many coastlines.
We can (& do) build flood mitigation structures: Levees, sea walls, pumping systems, drainage systems, floodgates, & more.
But we only engineer so big.
And they create vulnerabilities that tend to amp up the consequences of failures.
But we only engineer so big.
And they create vulnerabilities that tend to amp up the consequences of failures.
Engineered structures are always a +/- for risk reduction.
They usually to cut out less intense/more frequent hazards (small floods) while having little to negative impact on more intense/less frequent hazards.
But they also create a false sense of security.
They usually to cut out less intense/more frequent hazards (small floods) while having little to negative impact on more intense/less frequent hazards.
But they also create a false sense of security.
Every time I teach geology & disasters to engineers, I lay out the New Orleans Scenario, a culturally-important beloved city in a geological & meteorological tight spot with infrastructure that isn't keeping pace to changing hazard.
What do you do?
It has no good answers.
What do you do?
It has no good answers.
I don't know what's going to happen in the next few days. As always, I'm hoping a butterfly flaps its wings & doom dissipates without manifesting.
If you live in New Orleans, refresh your prep & keep an eye on official notices.
If you live far away, keep your compassion central.
If you live in New Orleans, refresh your prep & keep an eye on official notices.
If you live far away, keep your compassion central.
Everywhere has disasters, so no being smug that you don't have earthquakes or hurricanes or whatever is making headlines this week.
Everyone makes the best choices they can with the information and resources they have. Evacuation takes resources (blogs.scientificamerican.com/observations/d…).
Everyone makes the best choices they can with the information and resources they have. Evacuation takes resources (blogs.scientificamerican.com/observations/d…).
Social Media best practice for people outside the hazard area:
If this develops into a life-safety situation, stay off the disaster hashtags.
Leave them for official sources (officials, media) or people impacted. Any thoughts, prayers, theories, or at-home analysis is noise.
If this develops into a life-safety situation, stay off the disaster hashtags.
Leave them for official sources (officials, media) or people impacted. Any thoughts, prayers, theories, or at-home analysis is noise.
A small silver lining about countdown-to-doom: You've got time to prep.
The @FEMA app (fema.gov/mobile-app) is very good & includes tools for documenting damage.
Run down the checklist, especially what to pack/move higher up: ready.gov/floods
The @FEMA app (fema.gov/mobile-app) is very good & includes tools for documenting damage.
Run down the checklist, especially what to pack/move higher up: ready.gov/floods
Universal pre-disaster advice:
Find your local officials & info sources (emergency management, utilities, transport department, police, fire, public safety, politicians, local news...) to Follow on social media.
Overwhelmed? That's valid. Breathe & call:
Find your local officials & info sources (emergency management, utilities, transport department, police, fire, public safety, politicians, local news...) to Follow on social media.
Overwhelmed? That's valid. Breathe & call:
All that storm activity is making the Gulf a seething nightmare below the waves. No swimming this week pls.
Rip currents are nasty in part because our instincts are wrong.
That “calm break” in waves is where the current is strongest & most dangerous.
Swimming against a rip is dangerous & likely futile. Swim sideways (parallel to shore) to escape.
Learn more:
That “calm break” in waves is where the current is strongest & most dangerous.
Swimming against a rip is dangerous & likely futile. Swim sideways (parallel to shore) to escape.
Learn more:
Meanwhile in the Gulf: This weekend will be rough.
Weather data gathering point:
Weather data gathering point:
Real-time tide data.
Water levels in some locations already higher than the peak during Hurricane Michael.
Obey closures pls. The sketch factor just keeps getting worse.
Water levels in some locations already higher than the peak during Hurricane Michael.
Obey closures pls. The sketch factor just keeps getting worse.
We get a lot of data remotely — weather & ocean satellites, buoys, gauges — but it’s important to also “ground truth” what you think you’re seeing by gathering data from within storms.
Behold one of the most intense jobs on the planet:
Behold one of the most intense jobs on the planet:
Barry looks wonky but is carrying a LOT of water.
This hurricane is less about the wind and more about the water.
Water from the storm surge. Water from the rain. Water on top of high tides.
Flash floods. Overtops. Drainage failures.
Water from the storm surge. Water from the rain. Water on top of high tides.
Flash floods. Overtops. Drainage failures.
Storm surge is a bulge of water driven by high wind, low pressure, high waves.
Storm waves ride on top of the surge, getting a height boost. It’s a major source of damage. It’s even worse when it coincides with high tide.
Read more (& good animations): nhc.noaa.gov/surge/
Storm waves ride on top of the surge, getting a height boost. It’s a major source of damage. It’s even worse when it coincides with high tide.
Read more (& good animations): nhc.noaa.gov/surge/
Key point stays the same: “Turn around, don’t drown.”
Stay out of the water. Don’t try crossing the water. Don’t try floating on the water. The water is bad news. You don’t know what’s below the surface (contaminants, downed power lines...)
River status:
Stay out of the water. Don’t try crossing the water. Don’t try floating on the water. The water is bad news. You don’t know what’s below the surface (contaminants, downed power lines...)
River status:
It’s that final part of the pre-disaster countdown. By now, hopefully everyone is somewhere safe & STAYS. (Unless ordered to evac.)
Hazards from slow-moving storms can creep up on you (& odds of flash flooding climb as storm edges inland)
Last prep:
Hazards from slow-moving storms can creep up on you (& odds of flash flooding climb as storm edges inland)
Last prep:
