The role of near-record sea surface temperatures
Torrential rains inundated a heavily populated, steep-sloped area about 40 miles north of Rio de Janeiro on Tuesday and Wednesday, triggering flash floods and mudslides that have claimed at least 511 lives. Rainfall amounts of approximately 300 mm (12 inches) fell in just a few hours in the hardest-hit regions, Teresopolis and Nova Friburgo. Many more people are missing, and the death toll is expected to go much higher once rescuers reach remote villages that have been cut off from communications. The death toll makes the January 2011 floods Brazil’s worst single-day natural disaster in its history. Brazil suffers hundreds of deaths each year due to flooding and mudslides, but the past 12 months have been particularly devastating. Flooding and landslides near Rio in April last year killed 246 people and did about $13 billion in damage, and at least 85 people perished last January during a similar event.
Following fast on the heels of another extreme drought hitting the Amazon comes devastating Brazilian floods. According to scientists, this climate-whipsawing from mega-drought to mega-flood will become increasingly common as human emissions intensify the hydrological cycle (see Study: Global warming is driving increased frequency of extreme wet or dry summer weather in southeast, so droughts and deluges are likely to get worse). Indeed, it’s just happened to both Australia and this country (see “Hell and High Water hits Georgia“).
In this Wunderblog repost, Meteorologist and former hurricane hunter Dr. Jeff Masters has the story — and an analysis of the “departure of temperature from average for the moisture source regions of the globe’s four most extreme flooding disasters over the past 12 months”