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Question for earth scientists

TruthSeeker

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TruthSeeker
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I need help. The university has a new policy that all theses must be examined by someone far outside the field of study. So, although I know nothing about it, I am currently reading a thesis on modeling the internal boundary layer (IBL).

I am completely lost. The worst part is that the student does not define terms which he probably rightly assumes people in the field will grasp. However, I am way out of the field :D

So, I am wondering if I could get some basic help. Can someone tell me (if it is simple) in plain language (because I can find the complicated stuff using google), what "fetch" is. For instance, in this sentence "the equilibrium layer grows in thickness with fetch"

And, what is a "diabatic effect"?

I will probably add others later.

Thanks very much.
 
I'm not that familiar with this area of geology, but I believe that "fetch" is generally used to denote lateral distance. For example, ocean waves are affected by many factors, one of which is their "fetch," i.e., the length over which they travel.

"Diabatic effect" I've never heard of. Are you sure it's not "adiabatic effect"? Diabase is a type of rock, so I'm not sure what sort of effect it might have....

Sorry I couldn't be more help.

The university has a new policy that all theses must be examined by someone far outside the field of study.
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That's the stupidest thing I've ever heard.
 
Thanks. I think the concepts are finally coming together as he works through the derivation and comparison of different formulas for IBL.

Yes, this is stupid. I will be writing a letter to the faculty of graduate studies.
 
Is the point of this policy to force students to write clear and comprehensible theses? If so, the student must not have done a very good job -- unless of course he wrote the thesis before the policy changed. If so, that's really mean of the administration.
 
Wrath of the Swarm said:
Is the point of this policy to force students to write clear and comprehensible theses? If so, the student must not have done a very good job -- unless of course he wrote the thesis before the policy changed. If so, that's really mean of the administration.
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He submitted after the policy changed but I would guess he wrote before it did. I really can't and won't hold it against him that he did not go back and revise everything into a "for dummies" thesis.

We have a new VP Research. His main objective is to foster transdisciplinary and intradisciplinary collaboration. This initiative falls under that. I think he expects me to learn about the IBL and decide I must absolutely study its relationship to end of life care. It is stupid and I expect will be revoked as people complain. Although, last month, I read a thesis on film which I enjoyed.
 
Well, I suppose now you'll know not to build hospices or nursing homes next to active volcanos. See what a little transdisciplinary learning can do? :D

That really is quite unfair. It can take years to write an appropriate thesis, and some of the more technical fields aren't really suited for outside reading.
 
Wrath of the Swarm said:
Well, I suppose now you'll know not to build hospices or nursing homes next to active volcanos. See what a little transdisciplinary learning can do? :D

That really is quite unfair. It can take years to write an appropriate thesis, and some of the more technical fields aren't really suited for outside reading.
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Oh..so...the volcano view was a bad idea? hmmm...


You're right but I can't imagine anyone advising a student to write their thesis to cater to the external person. I also can't imagine an external person feeling they are qualified to "fail" a thesis. It's just a stupid formality. In terms of the exam, there are some standard questions you can ask even if you don't understand the thesis ~ limitations, future directions, applications to end of life care...
 
Wrath of the Swarm said:
Well, I suppose now you'll know not to build hospices or nursing homes next to active volcanos. See what a little transdisciplinary learning can do? :D

That really is quite unfair. It can take years to write an appropriate thesis, and some of the more technical fields aren't really suited for outside reading.
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Shoot, I have trouble reading theses that are outside my specialty, much less out of my general area.

And I don't want technical theses written for a general audience. They should be accessible to most people familiar with the field, but even then there will be aspects that only experts will really understand.
 
"Adiabatic" describes a process that takes place without heat entering the system. Gas expansion in refrigeration for example.
I never actually heard the word "diabatic", but dropping the Greek "a" prefix, would presumably negate the meaning of "Adiabatic"
"Diabase" is a U.S. term for a basic rock called "Dolerite " in the UK.

I never heard the term "Fetch" used in geology.

I'm confused about what you are studying. Can you clarify a bit?

-What is this IBL you mention for example?
-and what has it to do with Earth Science?
 
Soapy Sam said:
"Adiabatic" describes a process that takes place without heat entering the system. Gas expansion in refrigeration for example.
I never actually heard the word "diabatic", but dropping the Greek "a" prefix, would presumably negate the meaning of "Adiabatic"
"Diabase" is a U.S. term for a basic rock called "Dolerite " in the UK.

I never heard the term "Fetch" used in geology.

I'm confused about what you are studying. Can you clarify a bit?

-What is this IBL you mention for example?
-and what has it to do with Earth Science?
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Yikes...I don't know if I can answer this. A good test of my comprehension so far.

The thesis is from the department of earth science. IBL= Internal boundary layer. It is formed when air flows over a change in surface conditions including surface roughness, thermal and moisture properties. He hasn't defined diabatic (I always think he means diabetic!) but he is saying that there are special features of diabatic surfaces which require the IBL to be redefined. He is going to use (I'm not there yet) regression to predict temperature and humidity fields using IBL, fetch and diabatic index.

Or maybe it is something else entirely...I honestly can't tell you and reading this is making me feel incredibly stupid.
 
I know precisely jack about geology, but I'll vouch for the meanings of "fetch" as used above per my sailing knowledge.

You use "fetch" to get a feel for wave height (or calculate it, if you are mathematically inclined/have no life) in a given body of water with a wind of given speed from a given direction. For example, if you have a long, narrow lake (like, say, the Finger Lakes in New York) that is oriented North-South it probably won't develop much in the way of wave action if you have a west wind, since the wind doesn't blow over much water before it hits land again. However, with a North wind, the wind has the entire long distance of the N/S axis to build waves up, so you could expect some pretty big waves. (You use this knowledge to figure out where you want to anchor if there's a steady wind....you don't generally want to anchor on the south side of a body of water if you have a north wind blowing, etc)

Doing some googling just now on "'finger lakes' fetch +waves" I found a few papers discussing lake effect snow. Apparently if the wind is blowing along the long axis of a lake, it can pick up more moisture from the lake, leading to heavier snowfalls.

I'll second or third the notion that this review process is one of the stupidest things I've heard, and I'm not even in academia.

edited to clarify what I thought was stupid
 
well, if nothing else, I've learned what fetch is today.

But enough for today. I have "real" work to do and my tummy hurts and the peppermint tea isn't helping. :(
 
First, this has nothing to do with geology.

Climatology possibly.

The fetch of a wave in open ocean is the distance it crosses before hitting land. Again, nothing to do with geology, though I suppose geophysicists might apply the term to seismic waves. (Though I never heard it done).

Nor have I ever heard of an IBL in geology. There are lots of internal seismic boundaries in the Earth. (The Mohorovicic Discontinuity being the best known).

Boundary layer problems usually relate to the break up of laminar airflow over a surface (like an aerofoil), forming vortices as it enters turbulent flow and causing drag. Again, really, nothing to do with geology.

Atmospherics, climatology, meteorology, aerodynamics. That's more the area to look.

Seems to me you can only hunt for clarity of exposition and internal consistency. You can't realistically be expected to comment on content.
 
Soapy Sam said:
First, this has nothing to do with geology.

Climatology possibly.

The fetch of a wave in open ocean is the distance it crosses before hitting land. Again, nothing to do with geology, though I suppose geophysicists might apply the term to seismic waves. (Though I never heard it done).

Nor have I ever heard of an IBL in geology. There are lots of internal seismic boundaries in the Earth. (The Mohorovicic Discontinuity being the best known).

Boundary layer problems usually relate to the break up of laminar airflow over a surface (like an aerofoil), forming vortices as it enters turbulent flow and causing drag. Again, really, nothing to do with geology.

Atmospherics, climatology, meteorology, aerodynamics. That's more the area to look.
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Thanks Sam.

It's from the dept of earth sciences, so they must mean it very broadly. I'm thinking climatology since he's trying to predict temperature and humidity. I guess I addressed my thread incorrectly.
 
"Earth Science" is a broad church. Often includes "Geography" which can be anything from geopolitics to cartography to ecology.
I suggest finding the guy who dreamed up this policy and nailing his head to the floor. Might let some sense in.
Best of luck.
 
Soapy Sam said:
"Earth Science" is a broad church. Often includes "Geography" which can be anything from geopolitics to cartography to ecology.
I suggest finding the guy who dreamed up this policy and nailing his head to the floor. Might let some sense in.
Best of luck.
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Well, this afternoon he sent an email to one and all asking us to submit our research program for the next 5 years so that he can look for linkages and communalities. GROAN
 
Well, They told us to write our reports at an eighth-grade level (I have to translate this to what I experienced years ago--equivalent to a 5th-grade level) so that even politicians can understand them.
 
pupdog said:
Well, They told us to write our reports at an eighth-grade level (I have to translate this to what I experienced years ago--equivalent to a 5th-grade level) so that even politicians can understand them.
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Well, if a politician could understand it, then I might stand a chance :D
 
The university where I took my PhD in Rio has (or had) a similar policy, but the thesis usually do not travel outside the Geology department. I remember quite well that a paleontologist had to review a tectonics thesis, and he managed to understand very few of the main points of it.

Now, imagine an extreme case- someone say, from psicology, reviewing a quantum mechanics thesis.

This is the kind of idea that works well on paper, but not in the real world.

Also, it takes a lot of pages to make a technical text understandable by someone who´s not from that particular field. The integration of different fields can produce spetacular and unexpected partnerships, but from my personal experience, it works better when it starts on an informal way at the coffe break or at a pub.

Oh, your question... Sorry, I´m a geologist. When I started to read the thread I was thinking of internal mechanics adiabatic compression of rocks (diabatic? Never heard about), and that the IBL could be a name that I was not aware for some deep discontinuity.
 
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