Rare rainfall in the deserts of North Africa A look at recent shower activity in the usually dry Sahara

Fighters heading towards Sirte under clear blue skies [GALLO/GETTY]

The battle for control of Libya has become a familiar sight on our television screens over the last few months. A less familiar sight has been that of the fighting taking place during heavy rain. This has fallen over the Libyan coast as a trough of low pressure has moved through the Gulf of Sirte.
Other North African states have also seen some heavy rainfall. Algeria, at the start of the month, saw flooding around the town of el-Bayadh, which killed eight people, including three children swept away in a river flood.
Rainfall in the northern parts of Africa usually increases at this time of year as high pressure, situated over the Mediterranean, begins to withdraw. This allows frontal systems to move in from the northwest. In fact, climatologists identify 20^th October as the date when there is a significant pressure drop and much of North Africa can expect to enter the rainy season.
‘Rainy’ is a relative term, of course. There is a marked rainfall gradient from west to east across the North African coast. October rainfall in Benghazi is less than half that of Tripoli, 1000 kilometers to the west.
Over the last week there has even been some penetration of troughs into southern parts of both Algeria and Tunisia. Unfortunately weather observations, despite the best efforts of the World Meteorological Organization, are rather limited in this region, but computer forecasts certainly indicated the possibility of desert showers late last week.
Where rain did fall, then it is likely that dormant plant life would have been rejuvenated. The World Wildlife Fund estimates that on such occasions 50 percent of sand dunes and 20 percent of gravel plains may spring into life.
This is quite an unusual event. Most troughs and frontal systems tend to peter out before they reach the Sahara.
The other source of rain in this region is from the monsoon trough which meanders up from the south during the late summer. But it rarely reaches the southern part of the Sahara and it soon retreats southwards.
Throughout the Sahara rainfall does not exceed 25 millimetres (mm) per annum and in the eastern part of the desert it is less than 5mm. It is also hugely inconsistent and no rain may fall in some areas for many years.

You've stolen our weather! Iran's president blames the West for his country's water shortages

Iran's leader suspects the West of tampering with the country's weather patterns [GALLO/GETTY]

Love or loathe him, you cannot keep Iran’s President Mahmoud Ahmadinejad out of the news. His pronouncement that the country’s current lack of water is part of a plot by Western countries has caused much amusement in some quarters.
There is no doubt that Iran is suffering from a lack of water. Three quarters of the country is drought-affected and duststorms are a frequent occurrence.  Critics of Ahmadinejad’s government claim that the shortage of drinking water is the result of mismanagement of water distribution system and some two-thirds of available water is lost through wastage.
The President, however, is pointing a finger at the West. To be fair, this is a message he was issuing as early as May this year. So could there be an element of truth in his claims?
Although Mr Ahmadinejad is the son of a blacksmith, he was, until his appointment as Major of Tehran, a lecturer at the city’s University of Science and Technology, holding a PhD in traffic and transport. So he does have enough of a background in science to make his comments worthy of consideration.
Weather modification does have a long history. As early as 1947 the U.S. military was attempting to divert the course of hurricanes by seeding clouds with silver iodide. At the same time, the British were attempting to keep runways at military airfields clear by the use of long lines of burners, with the view to clearing any thick fog which had formed.
As recently as 2009, Chinese meteorologists claimed to have brought about Beijing’s earliest snowfall in a decade after seeding clouds with silver iodide in an attempt to end the ongoing drought. The resultant disruption to road and rail transport suggests that snow was probably not the objective of the experiment – a good soaking of rain was what they were really hoping for.
The problem with weather modification is whether it can be proved that the weather was indeed modified or whether it had occurred naturally.
It is likely that Mr Ahmadinejad was specifically referring to the use of electromagnetic waves to control weather. Quoted at the opening of a dam in the central province of Arak, he told reporters, “According to reports about climate, whose authenticity has been verified, the European countries have used certain equipment to discharge clouds and prevent rain-bearing clouds from reaching regional countries such as Iran.”
The ‘certain equipment’ to which he refers is probably that known as ‘atmospheric resonance technology’. This technology has a history stretching back to the work of Nikola Tesla in the late nineteen century. Tesla carried out experiments involving electromagnetic flux and the earth’s gravitational field.
Reports of experiments to use this technology for the modification of weather patterns can be traced back to the early 1990s and HAARP - High-frequency Active Auroral Research Program – an ionispheric research programme. In addition to the intended target of improved radio communications and surveillance, it has been postulated that such a programme could be used to alter weather patterns – an idea which has appealed to military strategists for many decades. But evidence that such schemes have been put into place is limited.
More recently, some relatively small-scale commercial operations have claimed to have ‘lassoed’ passing weather systems using methods based on electromagnetism to deliver rain to fee-paying customers.
For those concerned, like Mr Ahmadinejad, then a word of caution is required: such technology is much loved by internet conspiracy theorists. Similarly, an internet engine search for ‘chemtrails’ will lead the gullible to the belief that our every thought is being controlled by chemicals released from high-flying aircraft – although by whom is never made clear.
The uncertainty of weather does not sit well with our desire for ordered and controlled lives. Attempts to control our weather are likely to increase and there is every chance that they will meet with greater success in the future. But for the time-being, explanations for water shortages are more likely to be of a more mundane nature – such as leaky pipes, Mr Ahmadinejad.

Temperatures in the capitals of the world

Doha Qatar

Today's High: 35 C Winds: From the West 12 kph Tonight's Low: 26 C

TUE WED THU 33 C East 12 kph 26 C 34 C East 13 kph 27 C 34 C East 11 kph 27 C