How to convert potential temperature to temperature

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Alex5
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How to convert potential temperature to temperature

#1 Post by Alex5 » Wed May 06, 2015 2:37 am

Dear all,

I want to calculate ocean heat content which is defined by temperature. Does anyone know how to convert potential temperature to temperature. Thanks.

Alex

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wilkin
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Re: How to convert potential temperature to temperature

#2 Post by wilkin » Wed May 06, 2015 4:33 am

John Wilkin: DMCS Rutgers University
71 Dudley Rd, New Brunswick, NJ 08901-8521, USA. ph: 609-630-0559 jwilkin@rutgers.edu

fdaryabor
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Re: How to convert potential temperature to temperature

#3 Post by fdaryabor » Wed May 06, 2015 5:07 am

Dear,

You can use the attachment file.

Hope can help you.
Attachments
sw_temp.m
(1.86 KiB) Downloaded 190 times
sw_ptmp.m
the complementary function,

sw_ptmp: Potential temperature
(3.6 KiB) Downloaded 194 times
sw_temp.m
sw_temp: Temperature from potential temperature
(1.86 KiB) Downloaded 205 times

Alex5
Posts: 12
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Location: HongKong

Re: How to convert potential temperature to temperature

#4 Post by Alex5 » Thu May 07, 2015 4:48 am

Thanks a lot. I will try them. :D

Alex5
Posts: 12
Joined: Tue Oct 08, 2013 4:46 pm
Location: HongKong

Re: How to convert potential temperature to temperature

#5 Post by Alex5 » Fri May 08, 2015 2:19 am

wilkin wrote:There is a "seawater" toolbox

in Matlab
http://www.cmar.csiro.au/datacentre/ext ... awater.htm

or Python
https://pypi.python.org/pypi/seawater/
Dear Wilkin,

Could I ask another question, why roms use potential temperature instead of temperature? Actually, I am very new to ocean model, I am wondering if the ocean models prefer potential temperature. Thanks.

Alex

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wilkin
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Re: How to convert potential temperature to temperature

#6 Post by wilkin » Fri May 08, 2015 3:39 am

If you could put seawater in a container that insulates it from exchanging heat with any of the surrounding water, then move it from one depth to another, its temperature will change by virtue of the compression due to pressure. However, its potential temperature would not. That's basically the definition of potential temperature. So this is what we want in an ocean model - the model temperature only changes in response to heat exchange from surface fluxes or mixing with adjacent water of a different temperature. Just moving from one depth to another does nothing.
John Wilkin: DMCS Rutgers University
71 Dudley Rd, New Brunswick, NJ 08901-8521, USA. ph: 609-630-0559 jwilkin@rutgers.edu

Alex5
Posts: 12
Joined: Tue Oct 08, 2013 4:46 pm
Location: HongKong

Re: How to convert potential temperature to temperature

#7 Post by Alex5 » Fri May 08, 2015 11:34 am

wilkin wrote:If you could put seawater in a container that insulates it from exchanging heat with any of the surrounding water, then move it from one depth to another, its temperature will change by virtue of the compression due to pressure. However, its potential temperature would not. That's basically the definition of potential temperature. So this is what we want in an ocean model - the model temperature only changes in response to heat exchange from surface fluxes or mixing with adjacent water of a different temperature. Just moving from one depth to another does nothing.

Thanks for your explanation. :D

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