Updates below…

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We are all aware of the incredible rains and flooding in Queensland, Australia.  Nearer to home Brazil’s SE coast has been getting hammered as well.

At least 291 have died in all municipalities affected by floods and landslides, according to the Rio State Civil Defense Department, with scores still missing and thousands more left homeless. Residents of the three hardest hit mountainside towns worried over how long many other houses could cling to collapsing hillsides. News media reported nearly 400 dead.

Torrential rains that soaked the hills and mountains outside Rio for days finally pushed massive walls of sodden earth down onto the towns early on Wednesday

Death Toll in Brazil

Update: Deaths up to 538 on Friday and rains still coming…

It is pretty clear that the rains and flooding in Australia and the Philippines are due to the strongest La Niña in decades.  The warmer waters in the western Pacific add to the water load in the air, and therefore the fall of rain.  Since SE Brazil is on the western Atlantic and Sri Lanka, which has also had death-dealing floods, is in the western Indian ocean, it is not clear that La Nina might have any affect on those rains.

But [Nicholas Clingaman, a research scientist at Reading University's Walker Institute for Climate System Research]  says it is possible to make a link, though indirect, in the cases of Sri Lanka and Brazil.

“It’s basically a disturbance of the atmospheric circulation that makes it more conducive to rainfall in these monsoon driven regions … and in Sri Lanka we’ve been seeing some of these easterly winds blowing off into the Indian Ocean and interacting with the monsoon system there as well,” he said.

“Every La Niña and El Niño have a different character so it’s going to take a little while and some research to understand whether we can wholly blame the flooding in Brazil on La Niña,” he added.

Guardian UK

This doesn’t go to whether climate change, writ large, affects the intensity or rhythms of La Niña/El Niño [ENSO].  Australia has had catastrophic rainfalls, and catastrophic droughts before, though the floods of 1989, and the mid 70s are both, earthwise, in the very recent past.

The other odd thing worth noting is that typically the wet La Niña in Australia is accompanied by a dry California/Oregon.  It was been anything but dry here this time around.  Why that is, and why the two Big Wets are coming at the same time is not totally clear.  Some studies suggest that the warming at the poles, lifting more moisture into the air, has pushed the jet streams further south, creating entirely new weather patterns.

All to be understood, down the road.  Meanwhile, these events should be object lessons in preparedness for national, state and local agencies — as well as for all of us, neighbors and citizens.

A woman trapped on the roof of her car awaits rescue during the Toowoomba, Australia, flash flood on Monday. Image credit: Wikipedia.

Our favorite weather blogger Jeff Masters comments on both these events plus the incredible string of very heavy snowfalls on the East Coast this winter.

Update:  Warm ocean water contributed to the devastating rains in Brazil, as well as Australia.

Meteorologist Eugenio Hackbart, with the Brazilian private weather forecasting company Metsul, wrote in his blog today, “Heavy rains early this year coincide with the strong warming of the Atlantic along the coasts of southern and southeastern Brazil. With waters up to 2°C warmer than average in some places, there is a major release of moisture in the atmosphere essential for the formation of storms.”

From Jeff Masters at Wundergound

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