>> Login Sostenitori :              | 

RSS 2.0
TUTTI |0-9 |A |B |C |D |E |F |G |H |I |J |K |L |M |N |O |P |Q |R |S |T |U |V |W |X |Y |Z

Archivio Articoli Copia di Worldwide

Iceland Volcano – Weather and Agricultural Implications
  Text size
Eyjafjallajokull, the name given to a volcanic eruption in southern Iceland is actually the name of the glacier under which the eruption is occurring. The word “jokull” at the end means glacier. There are cone type volcanoes in Iceland but the majority of eruptions occur along fissures or great splits in the crust of the Earth.


Why Iceland?

imageEarth’s crust is made up of a thin hard layer that floats on magma, the molten material that when it reaches the surface is called lava. The crust is broken into plates that move as the magma underneath flows. In some places the plates collide as is happening where India crashes into Asia and the Himalaya Mountains are being formed. In other places the plates slide by each other as is happening with the San Andreas Fault along the west coast of North America. The third type of situation is when the plates pull apart as is happening right down the middle of the Atlantic Ocean forming what is called the Mid-Atlantic Ridge.
imageA string of volcanic islands along the ridge occur when the ocean surface is breached. Iceland is the largest of these conditions and is the beginning formation of a new continent. It will continue to grow as the plates spread. In all three conditions of collision, sliding and split, earthquakes and volcanic eruptions occur. The conditions and the impact vary in each case because of local conditions and latitude. Source Figures 1 a and b

Historical Events

The current fissure eruption occurring under the ice is aggravated because the heat melts the glacier so the added water intensifies the eruptive force. It also causes extensive local flooding with heavy rapid mudflows, which is a major concern for local residents.

These fissure eruptions occur all the time, although this particular region has been quiet for 200 years. The first observation and analysis of such events came from Benjamin Franklin who witnessed similar but smaller events as he sailed to France to take up his post as Ambassador. He attributed the 1783 event to Hekla a fissure strato-volcano in the south of Iceland,

but it was actually at Laki in the region of the current event. Here is what Franklin wrote.

During several of the summer months of the year 1783, when the effect of the sun’s rays to heat the earth in these northern regions should have been greater, there existed a constant fog over all Europe, and a great part of North America. This fog was of a permanent nature; it was dry, and the rays of the sun seemed to have little effect towards dissipating it, as they easily do a moist fog, arising from water. They were indeed rendered so faint in passing through it, that when collected in the focus of a burning glass they would scarce kindle brown paper. Of course, their summer effect in heating the Earth was exceedingly diminished. Hence the surface was early frozen. Hence the first snows remained on it unmelted, and received continual additions. Hence the air was more chilled, and the winds more severely cold. Hence perhaps the winter of 1783-4 was more severe than any that had happened for many years.

The Laki eruption continued for 10 months into 1784 and as Franklin anticipated had severe effect on crop production especially in France. It is likely the cause of the harvest failures that increased peasant unrest, already at fever pitch. Thus it became the catalyst for the French Revolution as the price of bread alone took almost all the peasants income.

Extent of Distribution

Volcanic dust from the eruption is already rising to 6 km and sometimes 11 km into the atmosphere and being spread across the Northern Hemisphere. Iceland is in the zone of the Westerlies, the great river of air that contains the Jet Stream. The pattern is reflected in the distribution of dust in Western Europe. (Figure 2)

Figure 2: Pattern of distribution of dust showing Jet Stream effect.Source
I wrote about the Jet Stream patterns here, and about the importance of volcanic dust here.

Aircraft are grounded as the very fine dust particles when ingested into the engines cause them to fail. It is a very dangerous situation that occurs whenever eruptions occur. Longer term the very fine material will remain suspended for several years. It will block sunlight causing cooling but because most of it is sulphur it will tend to block more in the yellow portion of the light, a part important for plant growth. We witnessed both the cooling effect and the delayed ripening of the crop following the eruption of Pinatubo in 1991.

Pinatubo had global impact that lowered temperatures by 1°C because it was at the equator and the dust is spread in both Hemispheres. The impact is discernable scientifically for a few years after depending on a variety of factors. This volcano will likely only impact the Northern Hemisphere depending on how long the eruption continues. It will aggravate concern already heightened by consecutive harsh winters. A similar pattern occurred following the eruption of Tambora in 1815 that was followed by 1816 known as “The Year with No Summer”. Byron wrote a poem about the atmospheric impact, which is a poetic description parallel to Franklin’s scientific observations and begins,

I had a dream, which was not all a dream.
The bright sun was extinguish’d and the stars
Did wander darkling in the eternal space.
Rayless, and pathless, and the icy earth
Swung blind and blackening in the moonless air;
Morn came and went – and came and brought no day
And men forgot their passions in the dread
Of this their desolation’

The impact for agriculture is disturbing because cooler growing conditions are already problematic. There is one positive side effect. Volcanic ash is almost the perfect fertilizer and so will increase crop yields after the temperatures increase again.

Aerosols are an important part of the entire weather and climate puzzle. If the eruption continues alarmists will use the cooling effect to explain failure of their computer models to anticipate the cooling currently underway. They won’t tell the public their models are unable to properly allow for the effect. Nature keeps reminding them how little they know and how wrong they are. It’s time the politicians started listening.

Source >  Canada Free Press

Home  >  Worldwide                                                                               Back to top


Libreria Ritorno al Reale

La libreria on-line di EFFEDIEFFE: una selezione di oltre 1300 testi, molti introvabili, in linea con lo spirito editoriale che ci contraddistingue.

Servizi online EFFEDIEFFE.com

Archivio EFFEDIEFFE : Cerca nell'archivio
EFFEDIEFFE tutti i nostri articoli dal
2004 in poi.

Lettere alla redazione : Scrivi a

Iscriviti alla Newsletter : Resta
aggiornato con gli eventi e le novita'
editorali EFFEDIEFFE

Chi Siamo : Per conoscere la nostra missione, la fede e gli ideali che animano il nostro lavoro.

Redazione : Conoscete tutti i collaboratori EFFEDIEFFE.com

Contatta EFFEDIEFFE : Come
raggiungerci e come contattarci
per telefono e email.

RSS : Rimani aggiornato con i nostri Web feeds

effedieffe Il sito www.effedieffe.com.non è un "prodotto editoriale diffuso al pubblico con periodicità regolare e contraddistinto da una testata", come richiede la legge numero 62 del 7 marzo 2001. Gli aggiornamenti vengono effettuati senza alcuna scadenza fissa e/o periodicità