Abstract.A sky temperature map at 45 MHz covering declination between +30 • and +60 • is presented. The sampling in right ascension is 20 min (∼5 • ) and 2 • in declination in most of the map. The originality of the work was to use cosmic emission measurements from five VHF StratosphereTroposphere (ST) radars collected during long periods of routine meteorological surveys. This map, which has an accuracy in temperature of about 600 K, is intended first for radar reflectivity calibration and system performance monitoring. The presence of two strong radio sources, Cassiopeia A and Cygnus A, can also serve as the verification of the beam diagram, beam width, and beam pointing direction of the antenna. Finally, this work is an attempt to show the potentiality of ST radar for astronomical purposes.

It is known that the insects observed in the lower layers of the atmosphere produce radar echos and that their spatiotemporal distribution is strongly influenced by the meteorological conditions and the thermodynamic structure of the atmosphere. However, the available information on the subject essentially deals with the continental zones. Observations carried out from the Atlantic coast with a polarimetric A^-band Doppler radar are used to show the existence of large band-shaped areas of insects above the coastal Atlantic Ocean, which has a reflectivity 3 x 10 2 times higher than the values usually observed inland. The insects collectively fly with a common heading. These bands form at dusk and are connected with the coastal atmospheric circulation, which carries along the local insect population.

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