[gradsusr] Confirmation of TCORR command

Thu Sep 24 06:24:36 EDT 2015

Thank you for these clarifications, Jim.

To follow up:
To use your suggested option (2), "define nino4 =
aave(sstanom,lon=340,lon=390,lat=-5,lat=5)"

Would I first need to redefine the longitude values
'set lon 0 360' ?

Best,
Andrew

On Thu, Sep 24, 2015 at 4:45 AM, James T. Potemra <jimp at hawaii.edu> wrote:

> Hi Abdus/Andrew,
>
> I'd be cautious of your nino4 as defined.  I presume your data are defined
> -180 to 180, where eastern longitudes are 0 to 180 and western longitudes
> are -180 to 0.  In your line:
>
> "define nino4=aave(sstanom,lon=-150,lon=160,lat=-5,lat=5)”
>
> the longitudes are in fact ascending (-150 is less than 160), however I
> believe this will create a mean from 150W eastward all the way around to
> 160E (again, assuming your longitudes are defined -180 to 180), a mean over
> 310 longitudes.  Instead you want 160E to 150E, or a mean over 50
> longitudes.  I further think Andrew's suggestion
>
> "define nino4=aave(sstanom,lon=160,lon=-150,lat=-5,lat=5)”
>
> will give an operation error (min lon > max lon).
>
> Instead you could try either:
>
> 1.  define two different boxes across the dateline:
> define nino4a = aave(sstanom,lon=160,lon=180,lat=-5,lat=5)
> define nino4b = aave(sstanom,lon=-180,lon=-150,lat=-5,lat=5)
> define nino4 = ( 20 * nino4a + 30 * nino4b ) / 50.0
>
> 2.  if the file is global and continuous, you might be able to use
> define nino4 = aave(sstanom,lon=340,lon=390,lat=-5,lat=5)
>
> Jim
>
>
> On 9/22/15 4:41 PM, MD ABDUS SATTAR wrote:
>
> Hi Andrew
> Thanks!
>
> On Wed, Sep 23, 2015 at 5:58 AM, Andrew Friedman <andfried at gmail.com>
> wrote:
>
>> Hi Abdus,
>>
>> I think that you are setting up the anomalies correctly. However, you may
>> have a problem with your NINO4 domain:
>> > "define nino4=aave(sstanom,lon=-150,lon=160,lat=-5,lat=5)”
>>
>> https://climatedataguide.ucar.edu/climate-data/nino-sst-indices
>>
>> In GrADS, longitudes need to be ascending.
>>
>> I think that you want to reverse your longitudes so you have
>>
>> "define nino4=aave(sstanom,lon=160,lon=-150,lat=-5,lat=5)” OR "define
>> nino4=aave(sstanom,lon=160,lon=210,lat=-5,lat=5)”
>>
>> Best, Andrew
>>
>> > On Sep 22, 2015, at 7:57 AM, MD ABDUS SATTAR <
>> <md-abdus.sattar at students.mq.edu.au>md-abdus.sattar at students.mq.edu.au>
>> wrote:
>> >
>> > Dear Andrew
>> > Thank you very much for your previous suggestion. Now, I can prepare El
>> Nino series as well as temporal correlation. However, I am not confident
>> enough whether I am right or wrong. I use the following script for
>> correlating El Nino 4 index with sea level pressure (Jan 1979 to Dec2014).
>> Please confirm me the following command.
>> > "reinit"
>> > "sdfopen \Temp\sst7914.mnmean.v4.nc"
>> > "set t 1 12"
>> > "define avesst=ave(sst1,t+0,t=432,12)"
>> > "modify avesst seasonal"
>> > "set t 1 432"
>> > "define sstanom=sst1-avesst"
>> >
>> > "define nino4=aave(sstanom,lon=-150,lon=160,lat=-5,lat=5)"
>> >
>> > "sdfopen \Users\mq43879691\documents\test2\mslp.mon.mean.nc"
>> > "set lon 0 360"
>> > "set lat -90 90"
>> > "set t 1"
>> > "d tcorr(nino4,mslp.2,t=1,t=432)"
>> >
>> > Output:
>> > <image.png>
>> >
>> > How can perform lead or lag correlation?
>> >
>> > Best regards
>> > Abdus
>> >
>> > On Tue, Sep 15, 2015 at 6:48 AM, Andrew Friedman <andfried at gmail.com>
>> wrote:
>> > Hi Abdus,
>> >
>> > Your timeseries is static because your boundaries for ssta do not have
>> a time-varying dimension.
>> >
>> > There are different commands, depending on what you’re trying to do.
>> >
>> > Are you trying to create a monthly ssta climatology? If so, check out
>> the instructions for the command ‘modify’:
>> http://www.iges.org/grads/gadoc/gradcomdmodify.html
>> >
>> > Or are you trying to create a running mean timeseries of ssta? In that
>> case, try something like ssta=ave(sst,t-11,t+0).
>> >
>> > Best,
>> > Andrew
>> >
>> >
>> > On Sep 13, 2015, at 8:01 AM, MD ABDUS SATTAR <
>> <md-abdus.sattar at students.mq.edu.au>md-abdus.sattar at students.mq.edu.au>
>> wrote:
>> >
>> > > Hi Andrew
>> > > I was trying to set tloop, but still facing difficulties. I prepared
>> the script as:
>> > > "reinit"
>> > > "sdfopen \Users\mq43879691\documents\test2\sst.mnmean.v4.nc"
>> > > "set t 1 1937"
>> > > "define ssta=ave(sst,t=1501,t=1933,12)"
>> > >
>> > > "set lat 25"
>> > > "set lon 50"
>> > > "set lev 0"
>> > > "set t 1501 1933"
>> > >
>> > >
>> > > "d tloop(aave(ssta,lon=100,lon=170,lat=-5,lat=5))"
>> > >
>> > > "d tloop(aave(sst,lon=100,lon=170,lat=-5,lat=5))"
>> > >
>> > > I can display time series of El Nino by using sst value ("d
>> tloop(aave(sst,lon=100,lon=170,lat=-5,lat=5))"). However, I would like use
>> to ssta ("d tloop(aave(ssta,lon=100,lon=170,lat=-5,lat=5))") and when I use
>> this the following map is found. Could you please suggest me in this
>> regards?
>> > >
>> > >
>> > >
>> > > <image.png>
>> > >
>> > >
>> > > Thanking you
>> > >
>> > > Abdus
>> > >
>> > >
>> > >
>> > > On Fri, Sep 11, 2015 at 4:18 PM, Andrew Friedman <andfried at gmail.com>
>> wrote:
>> > > Hi Abdus,
>> > > You may need to use ‘tloop’ with aave:
>> <http://www.iges.org/grads/gadoc/gradfunctloop.html>
>> http://www.iges.org/grads/gadoc/gradfunctloop.html
>> > > Andrew
>> > >
>> > > On Sep 11, 2015, at 7:05 AM, MD ABDUS SATTAR <
>> md-abdus.sattar at students.mq.edu.au> wrote:
>> > >
>> > > > Dear GrADS Team
>> > > > I am trying to calculate time series of El Nino SST anomaly in
>> January for a specific time period.
>> > > >
>> > > > I wrote my script as:
>> > > >
>> > > > "reinit"
>> > > > "sdfopen \Users\mq43879691\documents\test2\sst.mnmean.v4.nc"
>> > > > "set lon 100"
>> > > > "set lat 25"
>> > > > "set z 1"
>> > > > "set t 1 600"
>> > > >
>> > > > "define ssta=ave(sst,t=1,t=600,12)"
>> > > >
>> > > > "define elnino = aave(ssta,lon=100,lon=170,lat=-5,lat=5)"
>> > > >
>> > > > "d elnino"
>> > > >
>> > > > The GrADS did not know show anything by this script. On the other
>> hand, when I display only ssta setting lon 50 100 and lat 0 25; then it
>> shows the ssta. Can anybody help me in this regards?
>> > > >
>> > > > I look forward to your suggestion.
>> > > >
>> > > > Regards
>> > > > Abdus
>> > > > --
>> > > > Md. Abdus Sattar
>> > > > PhD Student
>> > > > Department of Environmental Sciences
>> > > > Level 2, Australian Hearing Hub Building
>> > > >
>> > > > Faculty of Science and Engineering
>> > > > Macquarie University
>> > > > NSW 2109 Australia
>> > > >
>> > > >
>> > > > Cell: +61404400401
>> > > > Email: md-abdus.sattar at students.mq.edu.au
>> > > >
>> > > > AND
>> > > >
>> > > > Assistant Professor
>> > > > Department of Disaster Risk Management (DRM)
>> > > > Faculty of Disaster Management
>> > > > Patuakhali Science and Technology University, Dumki, Patuakhali,
>> Bangladesh
>> > > >
>> > > > Cell: +8801716851612
>> > > > Email: abdus.sattar at pstu.ac.bd
>> > > > _______________________________________________
>> > > > gradsusr mailing list
>> > > > gradsusr at gradsusr.org
>> > > > http://gradsusr.org/mailman/listinfo/gradsusr
>> > >
>> > >
>> > > _______________________________________________
>> > > gradsusr mailing list
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>> > >
>> > >
>> > >
>> > > --
>> > > Md. Abdus Sattar
>> > > PhD Student
>> > > Department of Environmental Sciences
>> > > Level 2, Australian Hearing Hub Building
>> > >
>> > > Faculty of Science and Engineering
>> > > Macquarie University
>> > > NSW 2109 Australia
>> > >
>> > >
>> > > Cell: +61404400401
>> > > Email: md-abdus.sattar at students.mq.edu.au
>> > >
>> > > AND
>> > >
>> > > Assistant Professor
>> > > Department of Disaster Risk Management (DRM)
>> > > Faculty of Disaster Management
>> > > Patuakhali Science and Technology University, Dumki, Patuakhali,
>> Bangladesh
>> > >
>> > > Cell: +8801716851612
>> > > Email: abdus.sattar at pstu.ac.bd
>> > > _______________________________________________
>> > > gradsusr mailing list
>> > > gradsusr at gradsusr.org
>> > > http://gradsusr.org/mailman/listinfo/gradsusr
>> >
>> >
>> > _______________________________________________
>> > gradsusr mailing list
>> > gradsusr at gradsusr.org
>> > http://gradsusr.org/mailman/listinfo/gradsusr
>> >
>> >
>> >
>> > --
>> > Md. Abdus Sattar
>> > PhD Student
>> > Department of Environmental Sciences
>> > Level 2, Australian Hearing Hub Building
>> >
>> > Faculty of Science and Engineering
>> > Macquarie University
>> > NSW 2109 Australia
>> >
>> >
>> > Cell: +61404400401
>> > Email: md-abdus.sattar at students.mq.edu.au
>> >
>> > AND
>> >
>> > Assistant Professor
>> > Department of Disaster Risk Management (DRM)
>> > Faculty of Disaster Management
>> > Patuakhali Science and Technology University, Dumki, Patuakhali,
>> Bangladesh
>> >
>> > Cell: +8801716851612
>> > Email: abdus.sattar at pstu.ac.bd
>> > _______________________________________________
>> > gradsusr mailing list
>> > gradsusr at gradsusr.org
>> > http://gradsusr.org/mailman/listinfo/gradsusr
>>
>>
>> _______________________________________________
>> gradsusr mailing list
>> gradsusr at gradsusr.org
>> http://gradsusr.org/mailman/listinfo/gradsusr
>>
>
>
>
> --
> Md. Abdus Sattar
> PhD Student
> Department of Environmental Sciences
> Level 2, Australian Hearing Hub Building
>
> Faculty of Science and Engineering
> Macquarie University
> NSW 2109 Australia
>
>
> Cell: +61404400401
> Email: md-abdus.sattar at students.mq.edu.au
>
> *AND*
>
> Assistant Professor
> Department of Disaster Risk Management (DRM)
> Faculty of Disaster Management
> Patuakhali Science and Technology University, Dumki, Patuakhali, Bangladesh
>
> Cell: +8801716851612
> Email: abdus.sattar at pstu.ac.bd
>
>
> _______________________________________________
> gradsusr mailing listgradsusr at gradsusr.orghttp://gradsusr.org/mailman/listinfo/gradsusr
>
>
>
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>
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