Note that although the "wave" is seen in temperature, atmospheric pressure, sea ice and ocean height, the variations are hard to see in the raw data and need to be filtered to become apparent. Because the reliable record for the Southern Ocean is short (since the early 1980s) and signal processing is needed to reveal its existence, some climatologists doubt the existence of the wave. Others accept its existence but say that it varies in strength over decades.
The wave was discovered simultaneously in 1996 by Warren White and R G Peterson; and by Jacobs and Mitchell. Since then, ideas about the wave structure and maintenance mechanisms have changed and grown: by some accounts it is now to be considered as part of a global ENSO wave.