36 D. Rijks, M.W. Baradas Agricultural and Forest Meteorology 103 2000 27–42
• messages distributed by agricultural or other exten-
sion services; •
messages distributed by commodity services; •
posters in schools or local community halls. The choice of the channel, and of the ‘language’
used, has an influence on the efficiency of the use of the product. In certain cases, the emphasis may have to
be laid on the ‘consequences’ of the use or the non-use of the product, rather than on the product itself. The
monthly weather bulletin of Belize National Mete- orological Service Belize, 1998 is an example of a
communication that is consistently aiming to reach a great spread of users in a user-adapted manner. In In-
dia a special effort is made to render advisories attrac- tive and obtain feedback on their use Shaka, 1999.
Prudence or caution is required when ‘launching’ a new information product. Testing should be done
in-house first, and next in collaboration with the client, who must be aware of the test-aspect of the opera-
tion. A successful example of such a procedure was the pilot project in Mali Direction Nationale de la
Météorologie, 1998.
6. Assessing the value of the product
6.1. Feedback A product has value only to the extent that it is being
used to the clients’ satisfaction. Therefore, a feedback on the benefits that are derived from the decisions
based on such use, whether they be technical, social, economic, environmental or other, must be obtained
regularly.
A feedback may consider whether the value resides in minimizing damage, risk or costs, or in maximizing
output, net return or in enhancing the value of, or the possibility to exploit, other resources.
Examples of the former can be found in the applica- tions relative to the operations of the farming system
see Section 3, applications of the latter in the aspects of planning the farming system and adapting it opti-
mally to the inputs of another nature, that are avail- able. Quantified information on some of these exam-
ples is given by Rijks 1986, 1987. Munthali 1999 provides a summary of agrometeorological products,
requested by users in Malawi, on which feedback can be received.
Feedback on the indirect benefits, that materialise in post-harvesting operations and agro-industrial pro-
cedures is also very significant. Feedback can sometimes be expressed in the
manner of a diagram of costs and benefits Roux, 1992, where the relative costs and benefits of the
in-congruence between information supplied and reality can be expressed and more or less precisely
quantified. Appendix B gives the example of an appli- cation in pest and disease control. Part A of Appendix
B indicates a method of assessment of the success or failure of the forecast issued, part B identifies for
each combination of forecast and reality the origin of costs and benefits Rijks, 1992.
An example of an economic analysis of the use by farmers and horticulturalists in the Netherlands of de-
cision support systems for crop protection or irrigation management has been given by Molendijk 1999.
6.2. How will the product be paid for While one clearly must not frighten a potential
client by matters of cost, one has to inform oneself, unobtrusively, on the way the reward for the product
will materialize. Will there be a payment or a contri- bution to costs to the meteorological service, either
by individual clients or through a collectivity such as a commodity agency or a Chamber of Agriculture
or a marketing agency? Will there be a well-defined, well-expressed, recognition of the contribution of the
product to the work of the client such as a radio service, another Ministry, a government service, a na-
tional disaster relief effort, an international agency, that can justify the existence of a contribution on
the national budget? In some economic systems this question is openly accepted, in others it must still be
treated with care.
A few examples of economic benefits are given: •
In the Sudan Gezira irrigation scheme, the traditional crop sowing sequence is ground-
nut June–July, dura sorghum July, cotton July–August, and finally wheat in November, to
the extent that irrigation water remains available. In the early 1960s, the total area under wheat was
established somewhat arbitrarily, so that in some years the amount of water was insufficient to prop-
erly irrigate all wheat fields, while in other years unused water flowed down the river. More recently,
D. Rijks, M.W. Baradas Agricultural and Forest Meteorology 103 2000 27–42 37
fairly precise calculations of the total water re- quired by the cotton, sorghum and groundnut crops
for the remainder of their growth cycle have been made in October, compared with the irrigation wa-
ter available, and the remaining volume of water, and the potential area of wheat that could be
irrigated correctly, was then calculated. The net ef- fect has been that an average of about 20,000 acres
have been grown under wheat in addition to the area grown earlier, adding about 20,000 T, or more
than US 2M to the national economy. The cost of the calculations has been the time of a senior staff
member for about 3 weeks, using available weather and hydrological data, or a total of a few thousand
dollars Rijks, 1991.
• In Guadeloupe, banana plantations are treated with
fungicide against Mycosphaerella musicola, the agent that causes the Sigatoka disease that can
decimate production through leaf necrosis and de- creased fruit quality Fouré, 1987. In the past, a
standard 25 aerial treatments were given through- out each year. Application of meteorological infor-
mation to calculate the rate of development of the fungus and the subsequent need to treat the crop,
has allowed a reduction in treatments from 25 to 19 in the worst years and from 25 to 6 in the best
years. In the best years the resulting saving of 19 treatments meant a reduction in production costs
of about US 800 per ha. In the worst years the saving was about US 250 per ha. For a plantation
of 3500 ha the average of the savings amounted to more than US 1M annually, a multiple of the cost
of the meteorological station and the data analysis Rijks, 1987.
• In the Gambia, farmers store their groundnuts often
in heaps in the open air after harvest, until the buy- ing agents pass to collect the crop. Such heaps can
be seen up to 3 months after harvest, that is until January. Storage in the open air is favoured because
it permits continuous ventilation with the relatively dry air. If the dry pods are subsequently wetted,
the risk of contamination with Aspergillus flavus, and subsequent aflatoxin development, is great. The
price of aflatoxin infected groundnuts is often as low as 60 of the price of good groundnuts, which is of
the order of US 150 per ton. The total crop is of the order of 100,000 ton per year. During these months,
unseasonal rain can occur if there is an incursion of polar air at altitude. Provision of weather infor-
mation by local radio broadcasts can warn farmers for an impending chance of rain, so that they can
temporarily cover the crop with plastic sheeting, saving about US 60 per ton. Nationally, thanks to
such broadcasts, for each percent of the production saved, the benefit is US 60,000 Rijks, 1987.
• There are more than 1.5 million hectares of bush in
the Sahel on which sheep and cattle graze. A great part of the bush burns every year. Observations of
wind speed and direction, temperature and humidity can rapidly be analyzed, using a handheld computer
or a circular slide rule The Forest Research Insti- tute, Canberra, Australia, to indicate the speed and
direction of the movement of the fire, so that con- trol burning can be undertaken at the proper place
to stop the fire. A reduction of the burning on 1 of the area 15.000 ha allows the grazing of 5000
additional sheep, or an annual value to the G.N.P. of about US 100,000 Rijks, 1987.
• Overgrazing eventually leads to lower levels of
animal production and possibly desertification. Timely consideration of the limits of exploitation
of fragile environments in semi-arid areas, espe- cially of the soil and vegetation, as calculated with
cropvegetation models, can permit a planned max- imum sustainable
use, as a function of climate. With proper herd restrictions e.g. through the
preparation and sale of dried meat when herd re- ductions are required, a herd of n heads could be
maintained in an area indefinitely. If overgrazing is allowed to occur, a herd of say 1.3n heads could
perhaps graze for 3 years. After that, the sustain- able herd size may drop to 0.5n heads or even less.
After a 5-year period the restricted herd 10,000 heads×5 years=50,000 heads×years would al-
ready be more economical than the uncontrolled herd 3×13,000+2×5000=49,000 head×years;
in each subsequent year the economic gap grows, in addition to the long-term charge of restoring the
land to its original productivity Rijks, 1991.
• Another example concerns food supply through
coastal fishing. In Sierra Leone two seasons of storms occur, centered on March and October. Dur-
ing these months virtually no fishing boats go out, because of fear and uncertainty about the occur-
rence of storms, resulting in a forfeit of about 150 tons of fish per day. Analysis of past data shows that
38 D. Rijks, M.W. Baradas Agricultural and Forest Meteorology 103 2000 27–42
in each of these months daily forecasts can be made indicating the probability of occurrence of storms.
The results show that a high probability exists for 7 days, absence of storms for 7 days, and uncertainty
for the remaining 16 days. Fish that can be caught during the two times 7 days that no storms are fore-
cast, amounts to 14×150 tons or an annual value of about US 400,000. The cost amounts to dissem-
ination, on the local radio, of the client-oriented interpretation of a forecast that is in any case made
daily for other purposes Rijks, 1986.
• Gerbier and Remois 1977 developed a method
using meteorological information to determine each year the date for the harvest of grapes in the
Champagne region in France, that results in opti- mum quality of the champagne at lowest harvesting
costs. No economic data have been published by producers in respect of the use of such meteoro-
logical information, the only fact known is that one of the major houses finances the annual WMO
Norbert Gerbier-Mumm prize.
6.3. The clients’ perception Clients cannot be forced to accept products, but they
can be enticed. Subsequently they must remain con- vinced by the benefits provided by the product.
If satisfied, a client may give publicity for a product better than a meteorologist can do.
7. Conclusions
