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Five years after rain returns, climate modelers redo models and “predict” more, less, some, different or same rain

The same modelers were predicting drought and letting their friends nail their reputation to statements about how the dams would never fill, and Perth would be a ghost town. When Australia wasted billions on desal, they said nothing about the “extreme rain” coming. Then the endless drought broke, the rains returned, and now, years later, they’ve rejigged and tweaked their skillless models and put forward ambiguous, vague, yes-no-maybe, scare-scare-scary predictions that could have come from a tarot card reader.

Get ready for the full genius of expert modelling:

“There is no chance that rainfall in Australia will remain the same as the climate warms,” said an author of the paper UNSW Professor Steve Sherwood.

“The only way that this intensification of  falls at the lower end of the scale is if the continent becomes drier overall. The long and the short of it is that with 2°C of global warming Australia is stuck with either more aridity, much heavier extreme rains, or some combination of the two,” said Sherwood, from UNSW’s Climate Change Research Centre.

 — A hard rain to fall in Australia, Phys org.

Other, less astrological climate researchers have found that Australia has had megadroughts for the last thousand years (Vance et al 2014). Paleoclimate rainfall estimates likewise find that both droughts and floods used to be worse and longer (Tozer et al 2016). None of the UNSW climate modeling experts know why.

Perhaps the CO2-addicted models just don’t work at all because it’s the sun driving rainfall patterns?

Climate models don’t include any solar influence other than total sunlight. Yet Australian and Asian rainfall has been linked to solar activity for last 6000 years (Steinke et al 2014) .  Solar effects seem to shift wind and rainfall patterns over last 3000 years in Chile, while low solar activity means more central European floods. (Varma et al 2011, Czymzik et al 2016). Another study showed that when the sun is less active winters are likely to be warmer in Greenland with an increase in snowfall and yet colder in Northwest Europe. (Adolphi, 2014) The sun appears to control half of the groundwater recharge rate in China for last 700 years (Tiwari et al, 2014).

Models predicted that rain would fall more on wetter soils, but Taylor et al (2012) found rain fell on drier soils, and model feedbacks were wrong. See: Climate Models: 100% right except for rain, drought, storms, humidity and everything else.

They looked at the heaviest 1% of rainfall events experienced in Australia across all seasons with a particular focus on precipitation in the very different climates of Darwin, Sydney and Melbourne.

So they are investigating noise — rare events which need very long datasets to find a signal in.

The paper also went beyond the 2°C international Paris Agreement target, looking at what would happen with a 4°C rise in , which is a likely outcome based on current increases in the rate of carbon emissions. It produced a projected increase in rainfall for extreme events of 22-60%.

Why stop there? How about 6°C, 8°C,  10°C or eleventy-hundred*?

hat tip Pat, Geoff Derrick, Scott, Another Ian, AndyG, Albert Parker

REFERENCE

Adolphi, Florian, and Muscheler R., Svensson, A., Aldahan, A., Possnert, G., Beer, J., Sjolte, J.,  Björck, A., Matthes, K., Thiéblemont, R. (2014) Persistent link between solar activity and Greenland climate during the Last Glacial Maximum. Nature Geoscience; DOI: 10.1038/ngeo2225

Jiawei Bao et al. Future increases in extreme precipitation exceed observed scaling rates, Nature Climate Change (2017). DOI: 10.1038/nclimate3201

Czymzik, M., Muscheler, R. and Brauer, A. 2016. Solar modulation of flood frequency in central Europe during spring and summer on inter-annual to multi-centennial timescales. Climate of the Past 12: 799-805.

Stephan Steinke,*, Mahyar Mohtadi, Matthias Prange, Vidya Varma, Daniela Pittauerova, Helmut W. Fischer (2014) Mid- to Late-Holocene AustralianeIndonesian summer monsoon variability, Quaternary Science Reviews 93 (2014) 142e154

Christopher M. Taylor, Richard A. M. de Jeu, Françoise Guichard, Phil P. Harris & Wouter A. Dorigo ‘Afternoon rain more likely over drier soils’ will be published in Nature on 12 September 2012. www.nature.com DOI 10.1038/nature11377

R.K. Tiwari1,* and Rekapalli Rajesh2 (2014)  Imprint of long-term solar signal in groundwater recharge fluctuation rates from North West China. Geophysical Research Letters, DOI: 10.1002/2014GL060204

C. R. Tozer et al.: An ice core derived 1013-year catchment-scale annual rainfall reconstruction, The paper will be available for download from Hydrology and Earth System Sciences from 0900 AEST, 11 May 2016.

Vance et al, Interdecadal Pacifi c variability and eastern Australian mega-droughts over the last millennium (2014) American Geophysical Union, doi: 10.1002/2014GL062447

Varma, V., Prange, M., Lamy, F., Merkel, U., and Schulz, M.: Solar-forced shifts of the Southern Hemisphere Westerlies during the Holocene, Clim. Past, 7, 339-347, doi:10.5194/cp-7-339-2011, 2011. [abstract]  [PDF]

*A cheeky dig at people struggling to count.

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