- A lower level of the atmosphere resembling a tropical atmosphere, with minimal variation in temperature
- Soils in the vicinity of the storm containing ample moisture (the brown ocean)
- Latent heat from evaporation of that moisture measuring at least 70 watts per square meter of soil, averaged over a large enough area
Thursday, August 23, 2018
Exploring the Map vs Territory Problem - via the Brown Ocean Effect and Dr. Trenberth (revisited)
Time for something a little more thoughtful than jousting with Steele's LandscapesAndCycles snow job. Since Trenberth's talk at Fort Lewis College inspired my previously posted FCFP column; which in turn inspired Mr GOP to share Jim Steele's complain about the lack of debate; which in turn lead to the forgoing series examining Mr. Steele's base disingenuousness and which isn't quite finished yet.
Still, for now I figure it's only fitting that I share the other article I wrote regarding Dr Trenberth's talk. The Four Corners Free Press column was intended for the uninitiated, this essay is intend for climate science communicators and wannabe communicators regarding the under appreciated Map v Territory Problem. Food for thought. Originally written December 10, 2017, revised August 22, 2018.
On November 9th, 2017 Dr. Trenberth visited our local Fort Lewis College and was the featured speaker at an afternoon climate change symposium.
A Distinguished Senior Scientist (in the Climate Analysis Section at the National Center for Atmospheric Research), he is a cartographer if you will. His entire being is about getting the science, the models, the map, as close to representing reality as resources and ability allow. This dedication has made him among the best in his field of climate studies.
As a self-taught Earth and climate science enthusiast I’ve been familiar with his work for decades and have learned a great deal from his articles and in past years talks on YouTube and I was glad to finally have the chance to see and hear him in person.
He gave an interesting talk reviewing many aspects of our warming climate system including hurricanes, where he touched on the recent Hurricane Harvey with its extraordinary longevity and rainfall. Dr. Trenberth went through its vitals, a million people displaced, homes damaged, massive power outage, biblical rainfall.
He pointed out that normally hurricanes ‘peter out’ within on average 27 hours, whereas Harvey went for 70 hours on land making a loop and returning to the Gulf with it’s record warm waters, which fed the cyclone before it made another incursion onto land. Then he discussed the many human factors around Houston that ensure floods will reek maximum havoc, pointing out that, “with climate change you either adapt to it or you suffer the consequences.”
What struck me was that Trenberth didn’t mention the “Brown Ocean Effect” which is a fairly new, but fascinating and important observation based realization. Also, it’s another sure indicator of a warming world.
First discussed in 2007 with tropical storm Erin, then papers appearing in 2013 and then another tropical storm Bill in 2015. When I first read about it, it seemed to me one of those aha moments in science, ‘Of course, why didn’t we think of that!’
The reason for that degree of confidence in a fresh idea is that basic physics demanded it.
In a warming world, a more saturated atmosphere will result in more torrential rainstorms that will saturate the land. With higher temperatures, evaporation, convection, energy transfer. Given proper timing, of course a passing hurricane will feed off of this new resource, it’s what they do, whether you can accurately measure it or not. (Incidentally, so far observations have supported the thesis.)
The exact details are still being defined and will be different for every hurricane and not all inland hurricane intensifications include contributions from Brown Ocean Effect ( Officially TCMI, “Tropical Cyclone Maintenance or Intensification” ) since currently most inland intensifications can be categorized as Extratropical Transitions, such as 2012’s H. Sandy which are driven by different physical dynamics.
But the reality of this newly recognized geophysical dynamic is already well established:
“(1) an atmosphere warming to minimal temperature variations, (2) sufficient antecedent soil moisture from rainfall (even swamps or wetlands), and (3) evaporation rates that can provide enough energy to the atmosphere to mimic the ocean.” (source, Marshall Shepherd)
It’s significant because geophysics dictates that in a warming world the hydrological cycle will continue intensifying, meaning we must expect more torrential down pour events, often followed by hotter drier conditions, sucking moisture right back out of the ground faster. This in turn has cascading consequences. Such as feeding a well timed, well aimed hurricanes.
Given temperatures and the observations on the ground it seemed a pretty logical assumption to think it contributed to Harvey’s “Biblical” rainfall.
It was already mentioned by some scientists as a contributing factor to Harvey’s extreme longevity and rainfall, thus the omission stuck me as curious.
During the Q&A I had a chance to ask Dr.Trenberth, (58:00 video 3/3)
“I’d like to bring it back to Hurricane Harvey, can you explain what the Brown Ocean Effect is and how it impacts landfall hurricanes such as Harvey?”
Dr. Trenberth responded, “What, what is this?” and stopped. He caught me by surprise, after a couple beats I collected my thoughts and responded,
“The ‘Brown Ocean Effect is about land surface areas getting so saturated with hot water that when a hurricane comes over the land it starts sucking up the heat and moisture.”
I was startled at Dr. Trenberth’s halting response. Rather than reviewing what’s been written in the literature, he went back to the a,b,c’s of hurricanes. Thing is, none of that was being questioned. It was this ominous new environmental factor that I wanted to learn more about, but that Dr. Trenberth seemed to not want to talk about.
His 450 word two part response thankfully ended with:
“So that's presumably the brown ocean effect that if you've dumped a whole lot of water on the land there is a capability for some moisture to reevaporate back into the atmosphere to help refuel the storm if you like.”
I believe his reluctance can be understood by considering his ending sentence to part one:
“You know having a big dumping of water over land didn't hurt but I don't know just how much it helped either. That's the sort of thing that we can sort out a bit more with experiments with models at some later point.”
The true cartographer, until he can map it with his models and empirically define its details, nothing is more than a suggestion. Is this something to complain about? NO!
That’s his job, he is the scientist, the rigid conservative for whom every detail is of critical importance and assumptions are treated as poison. He could never have accomplished the extraordinary science that is his legacy without that fastidious rigidity.
It’s important that you dear reader understand this, none of what I’m writing here is a put down of Dr. Trenberth the scientist, this is about recognizing the Map v. Territory Problem and the need for more effective communication, specifically that student and the lay public have a responsibility to scientists to understand the issues and start defending serious scientists and their work wherever they come under disconnected from reality attacks.
Scientists can not and will not get in the trenches with agenda driven dogmatists, their time is too precious. But damit, someone needs to before Republicans totally destroy serious science and our democratic government Of The people, By The People, For The People based on rational liberal principles.
We live in the Territory and simply because scientists dedicated to the data and nothing but, have a hard time acknowledging connections doesn’t mean those connections aren’t there!
Our living breathing physical Earth is not a mental construct. Our changing biosphere doesn’t care about how much of the details we understand or not.
It is our obligation to understand our life sustaining Earth and part of that is filling in the missing pieces with honest rational conclusions based on our excellent grasp of this planet’s fundamental geophysics along with honest good-faith logic.
Instead, what we find is people in the audience using every flimsy childish excuse to downplay the reality of the situation we’ve created for ourselves. Or folks who are plain confused at all the words and shut it out.
These days articles are being written about the importance of story telling in conveying big ideas to people. The narrative needs to have a visceral connection with its audience. What could be more grand and potentially visceral that the grand pageant of evolution and the wonders of our global heat and moisture engine and how it impacts everything we have and do?
Our climate regime regulated weather engine with its folds within folds of harmonic complexity makes a wonderfully exciting story that ties right into Earth’s evolution - yet most are unaware. This isn’t about convincing contrarians, it’s about informing our own chorus, so that many more regular people start standing to protect the integrity of science and rational thinking and honesty and democracy and our pluralistic society.
Can’t help it, now it is political ! And third party “independent” dreams are more delusions that only seem to appear immediately before elections like so much tumble weed, only to fade until the lights are on again. In this real and pragmatic world only Democratic Party is the only show in town. Sick of all the political kabuki, help fix it.
We don’t need to like the Democratic Party, in fact this complacent party needs people that are feed up and angry and ready to change it. Dump the dinosaurs and infuse the Democratic Party with young blood and a rededication to facing the important problems and challenges of today.
We need to focus on fixing them and helping Democrats to win in November. Our American government, Of the People, By the People, For the People, depends on it! A healthy democracy requires an informed and engaged electorate.
Still no study that actually quantifies it for Hurricane Harvey, I’m sure some team is working on it.
That leaves us with the physics:
3 New Names and the Brown Ocean Effect
BY Jonathan Kinghorn April 26, 2018
Three things are needed for the brown ocean effect—as this phenomenon is known—to be possible: