This post is a comment on the meteorological aspect of the heavy rains last week in Spain. It begins with a quote from an earlier post, followed by comments to a video in Spanish and excerpts from various Wikis. Then I tried to find some data that could illustrate what happened. At the end, I make a few comments about what people think of the event and add my current perspective.
Yesterday at 11:53 PM I posted from an article:
However, I did not think I understood it well enough, so I looked for more explanations: I found a video in Spanish from BBC:
Qué es una DANA, el fenómeno meteorológico que provocó el peor desastre natural del siglo en España whch translated is "What is a DANA, the meteorological phenomenon that caused the worst natural disaster of the century in Spain"
The person is saying, from what I understand, that Jet Stream air circulating at an altitude of 11,000 meters, introduced cold air coming from Greenland over Spain which collided with humid warm air over the Mediterranean. (Warmer air can hold much more water vapor than colder air. When warm humid air is then suddenly cooled down, the water vapor condenses.)
The video has this text below:
Comment: Some in the global media landscape use every possible opportunity to push for the anthropogenic climate change narrative and the presented or implied solution of the green agenda. Burn less coal, oil, and gas and heaven will be restored.
Then I went to the Wikis. This can be both good and bad, but it still helped to make the concepts clearer after looking up a few entries:
The
English Wiki for "Cold drop" has:
The
German Wiki "Kaltlufttropfen" explains if translated:
Meteorologists refer to a high-altitude low in the upper troposphere as a cold air drop. It is created through a cut-off process.
The English Wiki has a note that suggests merging the "Cold drop" Wiki with the "Cut-off low" which explains:
[...]
Ventusky has a function that allows for searching the history, and I tried October 29. Here is a screenshot:
View attachment 103161
The air is coming from the ocean and it is probably humid. The dark colors indicate the amount of precipitation for the three-hour period. The temperature was 21 degrees. The humidity out at sea away from the area of rain was 90 %.
Then changing the parameters, here is a view of the airflow at an altitude of 5500 meters as well as an indication of the temperatures:
View attachment 103172
Near Valencia, the temperature at 5500 meters was -15 Celsius, while it near the low just south of Spain was minus 22 Celsius. Notice that the high-pressure system over the Atlantic brings cold air from the north to the south.
The Low then spins some of it around presumably causing the clash between cold and warm humid air from the Mediterranean.
Why are the temperatures in the low-pressure system so low compared to the surrounding air masses? I tried to scroll back in the records and found this picture for October 24. This was five days before the downpour. Notice that there is a tongue of cold air from the north, located southwest of Ireland. It has arrived there from higher latitudes and has been spun around by the high-pressure system over the Atlantic.
View attachment 103166
For October 25 the indications are that something is changing, the cold air from the north has separated and has begun to spin around itself in an independent low-pressure system.
View attachment 103167
On October 26, the situation is developing, the low is moving south.
View attachment 103169
October 27, two days before deluge day, shows a clear separation of the low that keeps moving south with the cold air from the north still spinning around itself. In the center of the low, it is minus 26 Celsius.
View attachment 103170
The day before the deluge, the temperature in the coldest areas of the low at 5500 meters is still minus 25 C.
View attachment 103171
There is still much I don't understand about the situation. Is it for instance possible that when the warm air coming from the sea hits land and is pushed up, is cooled down faster if there is already colder than usual air at altitude? Here is a geophysical map of the Iberian Peninsula:
View attachment 103174
While there have been speculations that the rains were assisted, it is difficult to prove they were. There seem to be reasonable explanations for what happened. However, since the governments of many countries have taught their populations to trust them, come plague, hell-fire, or high water, when something does show up where they don't know what to do, or are just plain incompetent, some try to cover their positions, when they know it is so bad that they could be fired or lose the confidence of the populations. Is that why the authorities in Spain, as reported in Spanish media, have had difficulties with counting the dead and the missing?
Agendas do differ, also in governments. Some want to keep their job at all costs. Many, hopefully, sincerely want to help their constituencies and the people they serve, but some may also allow a situation to develop in a certain way and allow others to cover their backsides, because the chaos of the mix of inability, negligence, incompetence, and contradicting rules and regulations not geared to such events, suits what they would like to achieve anyway. As the BBC video, (or was it really Google?) lost no pace to point out:
While many people in the Valencia area will have to struggle to get back on their feet, one message pressed on the global public seems to be that they need to go green, but also keep their minds shut, and their eyes closed to what is going on around them.