Friday 5 April 2013

Saharan dust events in western Crete


The Saharan desert plays an important role in the amount of dust particles that hover over Greece every year. Studies have proven that the Mediterranean area is mainly affected by the occurrence of intense cyclones called Sharav, that take place south of Atlas Mountains in Morocco.  However, the magnitude of the dust storms is seasonal, with lower velocity in winter, higher in the spring and somehow milder in the summer due to stable weather conditions [1].

In order to predict the atmospheric life cycle of the eroded desert dust, the Barcelona Supercomputing Center created the Dust REgional Atmospheric Model (DREAM) [2]. The picture below shows the amount of dust particles and the cloud coverage over the Mediterranean on the 21st of March, 2013, the day that most of our photos were taken. Crete appears to have high dust deposition levels. As mentioned above, dust events are common during spring season, the dates that we took our photos are random, we just happened to be around with a camera. Last February we had experienced a day with even heavier dust winds, especially in the area of Chania, unfortunately, due to lack of equipment we did not document it.



Quoting J.R.R. Tolkien “You can only come to the morning through the shadows.” However, when dust arrives from the Sahara desert, the whole day stays pretty much the same.

Morning in Frangokastello



The town of Chania under dusty clouds and strong south winds.




Chania - Rethymno highway

Note the sign at the end of the road. In a day with good visibility you would be able to read Irakleio 119km and Rethymno 41km!!!


On this turn some electric power pylons are slightly visible in the dusty atmosphere, unfortunately the rest of the scenery (White Mountains) is lost. 



Yellow Snow Peak

The intensity and regularity of dust winds over the last couple of months turned what was left of snow in the White Mountains to yellow patches.



Small fortress at Askifou plateau



Imbros

This is the entrance of Imbros village. Imbros is the last village that you will meet before starting to descend the mountain road towards the Sfakian plain and Frangokastello. At the far end you can see how the sky changes, as the mountains give way to open sky and sea.


Imbros gorge, where the mountain peak disappears in the dusty clouds.



Sfakian plain 

The photo clearly shows the massive effect that the Saharan sand has all the over the Sfakian region. The fortress of Frangokastello is located at the far end on the top tongue of land.




Monachus Monachus Apartments


The end of the day at Monachus Monachus Apartments comes with a dusty afternoon and predictions that in two days time the Mediterranean will be, once again, overflown by a plethora of tiny particles of sand [3]. 

Do not worry summer time is much clearer!







References:

1. P. T. Nastos, “Meteorological Patterns Associated with Intense Saharan Dust Outbreaks over Greece in Winter,” Advances in Meteorology, vol. 2012, Article ID 828301, 17 pages, 2012. doi:10.1155/2012/828301 (http://www.hindawi.com/journals/amet/2012/828301/#B11)

2. Data and/or images from the BSC-DREAM8b (Dust REgional Atmospheric Model) model, operated by the Barcelona Supercomputing Center (http://www.bsc.es/projects/earthscience/BSC-DREAM/)

3. Data and/or images based on the SKIRON/Eta modeling system (http://forecast.uoa.gr/)


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