Raining champions of the Arab world

Back in Soviet days, the Russian air forces regularly undertook seeding missions to make clouds dump rain early, thereby ensuring dry weather for ceremonial parades.

Morocco ’s Al Ghait programme is rather less trivial and represents part of a proactive response to the problems posed by drought.

Drought in Morocco , already a largely arid or semi-arid land, has become more frequent during the last decade. It often hits during the crop-growing season, with the two main periods frequently coinciding with seed germination/seedling emergence or affecting grain setting and growth.

Studies into climate change and global warming have shown that Morocco is among the countries that are most likely to be threatened by the effects of further climatic change. It has been calculated that the increase of temperature due to increasing concentrations of greenhouse gases in the atmosphere will be accompanied by a significant reduction in annual average rainfall. The reduction between 2001-21 has been calculated at four per cent with a 10 per cent during 2021-2050 and 20 per cent for 2071-2100.

This is serious, as Morocco has a diversified economy, but one that is still dominated by agriculture.

Morocco has, therefore, adopted a broad-based drought mitigation strategy, including water conservation measures, new agricultural techniques and new crop varieties.

Aviation has long had a part to play, especially in monitoring and measuring the effects of climate change. In 1982, the Al Ghait programme was launched, with aircraft taking a more active role.

The operation was a joint effort between the Government of Morocco and the United States Agency for International Development (USAID) and aimed to use weather modification techniques to augment rainfall.

The programme uses silver iodide as a seeding agent to increase the precipitation efficiency of cold clouds in the Central High Atlas Mountains. This causes snowfall, augmenting the snowpack in the mountains which, in turn, increases snow melt run-off in summer – just when it is most needed!

The silver iodide is released from ground-based seeding generators, or from aircraft (or both) when seedable clouds are in the target area.

In order to operate successfully over the mountains, the programme needed an aircraft capable of operating easily and autonomously at heights in excess of 8000m. A single RMAF Alpha-Jet (No.245) was modified for the task, gaining a new Sperry/Honeywell Primus 300SL weather radar in a slightly extended and recontoured nose, and with a modified AN/ALE chaff/flare countermeasures dispenser in the rear fuselage used for launching the cloud seeding silver iodide cartridges. The weather radar is used to help the crew to identify potentially dangerous cumulonimbus clouds.

The crew identies interesting cumulus clouds, which are then penetrated. Inside each, the pilot drops one or two silver iodide cartridges; these acting as a catalyst for the formation of raindrops.

During the first phase of field operations conducted from 1984-1989 an average of 15-25 storm events were seeded during each season, totalling 144 seeded days during the five-year period. This resulted in a 14 to 17 per cent increase in winter precipitation. These results were viewed as ‘encouraging’, but it was recognized that further research would be required.

The Al Ghait aircraft has also been used in a number of other African countries, including Mauritania and Burkina Faso in 1998.

Since 2002 the Moroccan Al Ghait programme has benefited from the involvement of the US company Weather Modification Inc (WMI) of Fargo , North Dakota .

WMI has been assisting in the development of the Al Ghait national cloud seeding programme and provided training. The US company kitted out a Royal Moroccan Air Force Beech King Air 100 (CN-ANA) with a WMI-2D2-C two-dimensional optical array ‘cloud particle’ probe, a 2D2-P precipitation probe under the starboard wing, and with other cloud physics instruments and cloud-seeding equipment.

Since 2005, the Alpha Jet has deployed to Dakar , Senegal every year during summer. A number of countries have now benefited from Moroccan experience and expertise in the field of weather modification and in 2007 Morocco won the Zayed ibn Sultan prize in the UAE in recognition of its efforts in this field.