<p><strong>CAN</strong> you? Sure, nobody on here is stopping you.</p>
<p>Is it meaningful? Not really.</p>
<p>The RMM indices are two separate metrics corresponding to the phase (interpretable using a phase space diagram)</p>
<p><a href="https://i.sstatic.net/bscgl.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/bscgl.png" alt="MJO Phase Space Diagram" /></a></p>
<p>(Example from <a href="https://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/forca.shtml" rel="nofollow noreferrer">CPC</a>)</p>
<p>If you want a more meaningful way to interpret the MJO, you can try <span class="math-container">$$\sqrt{RMM_1^2+RMM_2^2}$$</span> which should be the strength of the MJO, or the angle between <span class="math-container">$RMM_1$</span> and <span class="math-container">$RMM_2$</span> (probably using something like <code>atan2</code> in your preferred programming language.</p>

CC BY-SA 4.0
2020-10-09T16:00:08.090Z
2020-10-09T16:00:08.090Z
BarocliniCplusplus
<p>The RMM values are sometimes quite different. Can I average the values of RMM1 and RMM2 and use it as an index for MJO?</p>

<meteorology>
Can I average the two RMM values?
user1593039
# Can I average the two RMM values?

(Asked by: username_0 on 2020-10-09)

The RMM values are sometimes quite different. Can I average the values of RMM1 and RMM2 and use it as an index for MJO?

**Tags:** meteorology


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## 1 answers

### Answer by username_1 on 2020-10-09. Score: 1

**CAN** you? Sure, nobody on here is stopping you.

Is it meaningful? Not really.

The RMM indices are two separate metrics corresponding to the phase (interpretable using a phase space diagram)

[![MJO Phase Space Diagram](https://i.sstatic.net/bscgl.png)](https://i.sstatic.net/bscgl.png)

(Example from [CPC](https://www.cpc.ncep.noaa.gov/products/precip/CWlink/MJO/forca.shtml))

If you want a more meaningful way to interpret the MJO, you can try $$\sqrt{RMM\_1^2+RMM\_2^2}$$ which should be the strength of the MJO, or the angle between $RMM\_1$ and $RMM\_2$ (probably using something like `atan2` in your preferred programming language.


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