Meteorology of Saturday's Colombian Flood Disaster That Killed 254

[malaise]

https://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=3595
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By: Jeff Masters and Lee Grenci , 4:07 PM GMT on April 03, 2017

At least 254 people were killed in the in the city of Mocoa (population 40,000) in southwest Colombia near the border of Ecuador early Saturday, when torrential rains triggered a debris flow on a nearby mountain that surged into the town as a huge wall of water carrying tons of mud and debris. The disaster is the fourth deadliest weather-related disaster in Colombia’s recorded history. Reports from Colombia indicate that 130 mm (5.1”) of rain fell during a short period on Friday night and early Saturday morning, with the heaviest of the rain falling in just two hours, between 23:00 Friday, 31 March and 01:00 Saturday, 01 April, 2017. The rains fell on soils that were already wet from unusually heavy rains during March; the Mocoa region received about 50 percent more precipitation than usual during the month of March. The heavy rains of Saturday morning triggered a debris flow down the Taruca ravine on the northwest side of Mocoa, and this landslide, accompanied by floodwaters, poured into the Sangoyaco River and rampaged through the city of Mocoa. According to a USA Today interview with Jonathan Godt, coordinator of the U.S. Geological Survey’s landslide hazards program, “That mixture can move at 35-40 miles an hour, and because it’s so dense it has a lot more momentum and destructive power than water alone.”

Contributing causes to the disaster
The fundamental cause of the disaster was that the city of Mocoa was situated in a vulnerable location—in a valley surrounded by steep slopes, close to the Mocoa, Mulato, and Sancoyaco rivers. Deforestation on the surrounding slopes may have contributed to the landslide and flood. President Juan Manuel Santos blamed climate change for triggering the flood, and he has a point—increased evaporation from warming oceans have caused a significant rise in atmospheric water vapor and very heavy rainfall events like the Mocoa event in recent decades. The Mocoa rains were triggered by a very moist flow of air from the tropical Atlantic, where ocean temperatures were near average (see the meteorological analysis below.) The rainy season in Colombia extends from March to mid June, so additional floods and landslides can be expected the next two months.

[catbyte]

1. Oh my God, how awful. There'll be more tragedies like this thanks to greedy

Republicans. What's the worst thing about it is Americans will be able to ignore these events because they're happening to "those brown people down there," which is so very wrong and short-sighted. Our generations in power now will have a lot to answer for.

[malaise]

2. Truth is that you'll find versions of them

right across the planet. You're right re the fact that these disasters will be ignored by the Con and his ReTHUGs

[pansypoo53219]

3. DEFORESTATION helped create this as well.