Complex sentence: Edmonton's Carvel radar, was one of only three Doppler weather radar to exist in Canada at the time, and later became part of the Canadian weather radar network which was Dopplerized starting in 1998.
Split into simpler sentences: Edmonton's Carvel radar was one of only three Doppler weather radar to exist in Canada at the time. It later became part of the Canadian weather radar network, which was Dopplerized starting in 1998.