Re: [ferret_users] Composite Event

[Deni Okta Lestari <deniokta.lestari28@xxxxxxxxx>]

Thank you for answer my question. In that case, the composite will calculate average precip when the index is larger than the threshold. How about to capture specific season?  For example, to evaluate the evolution of ENSO event ( e.g JJA(0), SON(0), D(0)JF(1), MAM(1), JJA(1)). 

Best regards,

Deni

On Sat, Dec 22, 2018 at 1:04 AM Ryo Furue <furue@xxxxxxxxxx> wrote:

Dear Deni,

On Fri, Dec 21, 2018 at 3:00 PM Deni Okta Lestari <deniokta.lestari28@xxxxxxxxx> wrote:

I am using 250 years precipitation data. I am trying to composite the precipitation during ENSO event by using NINO index. kindly help me to produce composite analysis using conditional if ?

Assuming that the timeseries of the Niño index has exactly the same time axis as your precipitation variable,

let masked_precip = if index gt threshold then precip

In this way, the new precipitation variable is defined only when index is larger than the threshold.  Then your composite is a simple average over the time axis because the averaging operator ignores undefined time steps.

Hope this helps,

Ryo

 

Best regards
Deni

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Deni Okta Lestari

Ilmu Lingkungan

Program Pascasarjana Universitas Sriwijaya

Email: deni.oktalestari28@xxxxxxxxx

Mobile:+62-852-6758-0477