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Hallelujah — rain coming

Good rain forecast for East Coast fire-grounds 15 – 50mm.

Probably thanks to the MJO which Joe Bastardi told us was strongly building nine days ago. The northern monsoons have finally started, and the peak MJO position for rainfall has arrived. It won’t end the drought yet, but it might put out some fires.

Rain forecast BOM Australia.

Rain forecast BOM Australia.

 

As Joe Bastardi explained, there is an extreme Madden-Julian Oscillation going on north of Australia.  We’ve launched into “Phase 5” with a rocket, and “wow” — things are far out on the phase diagram. Looking at past MJO patterns the wiggles can loop, dive to the centre, swing wildly out, though I didn’t see any with such an extreme phase 5. They can resemble the flight path of a bee. Predicting what any MJO does next looks difficult, and next week it may have retracted to low normal “six”. Who can say?

Madden-Julian Oscillation map current. 2020. Australia.

Madden-Julian Oscillation map | Source: Australian Bureau of Meteorology

The BoM does an average forecast of what different phases of the MJO mean for Australian rainfall. I’m not sure how much it would change in an extreme MJO.

MJO Australia phases. BOM. Bureau of Meteorology.

For those who want more information on the MJO, this recent study looked at how it affected Halls Creek rainfall in northern WA.

 Other major drivers of rainfall at Halls Creek include El Niňo and La Niňa conditions, the Indian Ocean Dipole and regional soil moisture (Sharmila and Hendon 2019).”

No wonder predicting seasonal rain in Australia for our farmers and fire fighters is so difficult. Until we understand the solar, lunar and geothermal drivers of these ocean currents we have NFI. Perhaps the complexity is too chaotic in any case, but we are “not even wrong” at this point. Our current models treat the sun as if it were a simple ball of light, not an electro-magnetic dynamo (or two dynamos) and don’t include most solar, some lunar and — as far as I know — no geothermal or geomagnetic factors (because we haven’t even mapped out all the volcanoes and hot springs under the sea, let alone measured them, nor measured the trends and figured out what drives them).

And we wonder why they fail?

 

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