An assessment of field readiness for wireless sensor based weatherboards ??? A calibration report

The ability to provide timely, reliable and relevant weather forecasts by the National Meteorological Services in most countries in Sub-Saharan Africa is hampered by among other things, the lack of adequate coverage by weather stations. The cost of acquiring and running such stations is beyond reach of many governments in this Region and alternative technologies such as the sensor-based weather stations have been identified as one way of addressing this problem. Although these sensors could extend the weather network coverage and eventually enhance weather forecasting, the acceptability of such data by the meteorologists is only possible if the sensors are calibrated and their field readiness evaluated. This paper is a calibration report towards this end; it details a rigorous assessment of sensor-based weatherboards along three factors: (1) calibration (lag, random, and systematic) errors; (2) effects of enclosing the boards in an enclosure constructed from perspex material; and (3) battery depletion rates. The results indicated that although calibration errors could be corrected by appropriately programming the boards, and battery depletion by the use of flexible micro-solar panels, the sensor boards described in this paper were not ready for use in the field until an enclosure designed with the input of meteorologists was put in place.