MW&A

Hydroclimatology and Solar Explorations

Climate & Weather Representations

The Maddening Julian Oscillation

The Madden Julian Oscillation (MJO) is a monthly, or bimonthly, or trimonthly, or weekly, or some variation between all of those, migration from west to east of precipitation patterns along the equator, or along the tropics, or along the entire planet.  It is influenced by temperature patterns and it influences temperature patterns.  It influences monsoons and it is influenced by monsoons.  It is key to understanding global climate change, even though it is inconsistently defined.  As I noted, its patterns are asserted to be sub-annual or even sub-weekly, yet decadal-scaled, fossil fuel emission inspired global circulation models strive to replicate it.  Some claim success in doing so, even though they cannot otherwise accurately project/predict a single precipitation pattern anywhere in the world at any decadal time in the future.

If you find this incoherent and maddening, then you are of a like mind with me.  If the MJO cannot be defined, then it cannot be reproduced.   Much of my concern stems from an official US Climate.gov page at

https://www.climate.gov/news-features/blogs/enso/what-mjo-and-why-do-we-care#comment-3275

The authors of that site are “Michelle L’Heureux (NOAA Climate Prediction Center), Emily Becker (University of Miami/CIMAS), Nat Johnson (NOAA Geophysical Fluid Dynamics Laboratory), and Tom DiLiberto and Rebecca Lindsey (contractors to NOAA Climate Program Office), with periodic guest contributors.”

I have submitted a few comments there but those have been removed, so I’ll comment here.  First it would be nice if they could get the time frame straight.  The first image set at their page, captured below, initially seems to be roughly monthly.  That would almost align with a 2005 peer reviewed paper by Chidong Zhang [1], which claims:

The Madden-Julian Oscillation (MJO) is the dominant component of the intraseasonal (30-90 days) variability in the tropical atmosphere.”

I even wonder about that wide range, but in any case, Zhang limits the minimal length to 1 month.  The first graphic at the Climate.gov page show some kind of time span via so called Phases along the right margin of that set of images, but the definition of “phase” appears both muddled and self-contradictory.

The figure caption refers to “eight phases described in the text”.  But the text refers only to two phases, and in that context they appear to only refer to above (phase 1) or below (phase 2) the equator.  There is a mention of eight stages.  Even if Climate.gov is given a pass there, more questions sprout like mushrooms.  The period is from November through March.  That’s only 5 months.  The source suggests that the MJO varies on a “week to week basis”.  My math suggests then about 20 phases (or stages).   With all of these inconsistencies, I wonder how one could even verify if those phases (stages) are constant time steps?

There are further inconsistencies at that site.  Their second image is a crude animation in which each frame apparently spans only 5 days.  Even that is not ‘week to week’.  Moreover the animation is not sequential, as the featured extraction I posted at the very top demonstrates.  I noted this concern to the scientists (Anthony Barnston?) that the June 12 frame occurs after the May 8 frame and before the May 13 frame.  I hope they will repair that at least, and cite abeqas for bringing it to their attention.  The post had been up since 2014, so it is amazing to me that no one has noticed this before.

Maddening Time Traveling Madden Julian Oscillation.

I place this squishy and malleable notion into the same category as ENSO.    Since ENSO is actually a compendium of over a dozen indexes, scattered across the Pacific, atmospheric and ocean scientists can always point to some combination of its components to have preceded a drought or flooding, or warming or cooling event, somewhere.  Whatever event was not properly anticipated by fossil fuel greenhouse gas emissions global climate models, any climate change researcher has a ready option to explain it away by reference to ENSO, or MJO, or the AMO, or the PDO, or AMOC, or Volcanos, or CFCs, etc.  I believe that there are now over 100 such indexes or parameters that one can dredge up to paper over any particular wrinkle in the greenhouse gas climate forecasting complex.

If the MJO is actually a MONTHLY scaled phenomenon that is truly INTRASEASONAL, I have a ready resource to compare it to.  I have reposted my favorite geostrophic monthly moisture animation below.  It is explained in detail here.  Briefly, the blues are precipitation and the greens are evaporation.  Take a look as the equatorial anchored moisture sweeps north and south across the planet, like windshield wiper blades.   Yet in contrast to that, Climate.gov and Zhang assert that the moisture pattern migrates east from the Indian Ocean, ALONG THE EQUATOR.   Can any identify anything like the MJO in this 12 month animation?  I can’t.  I see north and south (monsoonal) patterns.  I see mid-latidude patterns of easterly migration of moisture (well in line with everything else we know about mid-latitude circulation).  I see some interesting polar patterns.  But no MJO pattern can be identified.

Click on image to animate

I can turn this on its head as well.  In my animation as noted one can clearly identify the meridional (north and then south etc) shifting of the Equatorial Trough (the blue equatorial band).  No such shifting can be recognized in Climate.Gov’s Figure 1 which I’ve reproduced near the top.  Given that they don’t identify the dates of each of their 8 frames, this adds to the puzzle.  I would expect to have seen a slight shift south from November through Jan followed by a slight shift north through March.  But again no dates were provided.  Who then is to say whether the entire span covered only a few days or weeks?   Accordingly I have submitted a third comment to their site and I include that below:

The MJO appears hard if not impossible to corroborate when I compare their claims to the satellite reanalysis data set that I use, which largely covers the same broad time span. But even with “my” set, there are nonetheless some interesting zonal (EW or WE) cycles or shifts at some seasons.  I personally follow this occasional pattern shown below for, in this case the months of January through April, in 2005.  In the coverage above I developed an average of precipitation and evaporation (for the full atmosphere) for each month extracted from a 36 year satellite era span.  In the mini animation below, I use information specific to 2005 only.  I’ve also overlain some streamlines (again for the full atmospheric thickness).  The yellow lines and the red lines originate along north-south strips to the east of the central Pacific.  So one can easily see how the Pacific equatorial full atmospheric flows change directions across these selected months.  In the remainder of the year, Easterlies (flow then from east to west) along the Equatorial Trough consistently prevail.  Although I picked 2005, simply because the MJO enthusiasts like that year, the pattern I show is not uncommon at all.

Click on image to animate. Note switch in equatorial flow directions for alternate months.

Accordingly this seems like a more reproducible and possibly useful cycle than the MJO.  If this pattern has previously been identified, I welcome an opportunity to apply its original name and to cite.  If not, then I’ll call it the My Koalas Oscillation (MKO).  It is a recurring pattern over the early calendar months of the year, where normal (full atmosphere thickness) easterly tropical flows are temporarily diverted into the adjacent spinning gyres.   I think that is fully reproducible and this page can be cited.

[1] Zhang, C.  2005.  Madden-Julian Oscillation  Rev. Geophys.  43.  RG2003, doi: 10.1029/2004RG000158.

This is only an informal blog post.  Corrections are welcome through comments only.

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