Is there a future role for altimeters carried on micro platforms for the early warning of surface hazards?
Thomas Donald Allan(1)
Satellite Observing Systems Ltd,
15 Church Street,
Godalming, Surrey GU7 1EL,
Satellite monitoring of the ocean surface could be revolutionized by the introduction of constellations of small, low-cost platforms carrying special-purpose altimeters to complement dedicated, high precision research missions. The latter have proved invaluable in revealing details of the ocean’s surface currents and eddies that contribute to global climate. Their sampling remains inadequate, however, for providing rapid warning of impending dangers which can develop at sea within a matter of hours.
The EC GAMBLE study (to which over 40 European organizations contributed) demonstrated that even for the detection and tracking of relatively slow moving eddies, single altimeter missions with revisit times of many days could not keep up. It was shown that the introduction of microplatforms could potentially benefit both research and daily marine operations by capitalizing on the altimeter’s ability to make contemporaneous measurements of sea surface height, wind speed and significant wave height.
The tsunami wave which engulfed coastlines around the Indian Ocean over a year ago was detected, quite fortuitously, by JASON passing over the area some 2 hours after the ‘quake. It required the greatest marine disaster in living memory to focus world attention on the awesome power of the sea. But the severe storms across the globe that cause damage, delay and loss of life are almost a daily occurrence.
We discuss how greater sampling could be achieved at an affordable cost, how long-term ocean and climate research would benefit, and how an early warning system of approaching storms at sea could include a tsunami detection mode.