First in-situ measurements of HF radar echoing targets

• Published in: Geophysical Research Letters
• Main Authors: Moen, J., Oksavik, K., Abe, T., Lester, Mark, Saito, Y., Bekkeng, T. A., Jacobsen, K. S.
• Format: Article in Journal/Newspaper
• Language: English
• Published: American Geophysical Union 2014
• Subjects: Science & Technology; Physical Sciences; Geosciences; Multidisciplinary; Geology; F-REGION IRREGULARITIES; CUSP; BACKSCATTER; CLEFT; LAYER; Svalbard; Leicester
• Online Access: http://onlinelibrary.wiley.com/doi/10.1029/2012GL051407/abstract; http://hdl.handle.net/2381/28756; https://doi.org/10.1029/2012GL051407

The sounding rocket Investigation of Cusp Irregularities 2 (ICI-2) was launched into the cusp ionosphere over Svalbard to investigate the production of decameter scale irregularities in the electron plasma associated with HF radar backscatter. The main mission objective was to obtain high-resolution measurements of decameter scale electron plasma irregularities and to quantify the growth rate for the gradient drift instability (GDI). At the 5.7 kHz sampling rate of the absolute density measurements, ICI-2 has provided the first documentation in terms of absolute electron density measurements of how 10-m structures are located on km scale electron density gradients. ICI-2 traversed a cusp electron density structure created by ongoing soft precipitation. 10-m scale irregularities were generated at km scale density gradients. The estimated growth time for the GDI process was 10–50 seconds. SuperDARN operations at the University of Leicester were supported by STFC grant PP/E007929/1, and ML is funded by STFC grant ST/H002480/1 Peer-reviewed Publisher Version 112057