The power of microwave remote sensing for studying the oceans of the world was demonstrated conclusively by the SEASAT mission in 1978. Since then, no further satellite-flown instruments have been available to provide further data of this type. However, the proposed launch of ESA's ERS-1 satellite will lead to a new set of active microwave instruments being flown in space in 1990. Even though similar data has been obtained from aircraft-flown instruments SAR, scatterometers, altimeters etc. - a great deal of activity has been taking place to develop the necessary expertise in handling and...