Long-range aircraft as an Arctic Oceanographic platform

Synoptic basin-wide measurements of Arctic Ocean temperature and salinity are now possible with the recent development of an expendable conductivity, temperature, and depth probe for deployment from aircraft (AXCTD). Both the P-3 Orion aircraft and the C-130 aircraft are capable of long-range, low-altitude flight and are ideal for Arctic research. Expendable profilers can be quickly deployed over vast regions from aircraft and in locations with limited ship access, but have the disadvantage of measuring only the top 1000 m and of being about an order of magnitude less accurate than a CTD cast, primarily because of noisy salinity measurements and depth-fall rate errors. We explore how to conduct an ACXTD measurement program in ice-covered seas and discuss a test of these methods conducted in the Arctic Ocean's Eurasian Basin. Long-range aircraft can significantly augment the present program of Arctic research by performing large-area surveys, continuing time series with repeat measurements, and by helping target locations for more detailed and accurate shipboard measurement.