Ocean teleconnections between Antarctica and the Equatorial Pacific and Atlantic.

It is well known that the equatorial ocean-atmosphere system plays a key role in global climate events such as the El Nino-Southern Oscillation (ENSO) phenomenon. There is now compelling evidence that changes in the Antarctic can strongly and quickly affect the equatorial ocean and the ENSO cycle. Observations demonstrate statistically significant correlations (teleconnections) between the Antarctic and the Equator with leads and lags of order months. Model simulations strongly suggest that these teleconnections are a result of propagation of particular types of ocean waves between the Southern Ocean and the Equator. These waves, known as planetary waves, owe their existence to the Earth's rotation. ENSO is of fundamental importance to the social and economic well being of large numbers of people and indirectly to that of Europe. There are therefore huge potential scientific and socioeconomic benefits from increased predictability of ENSO and its impacts such as severe flooding, droughts and disruption of fisheries. However present ENSO prediction systems take no account of Southern Ocean influences. We propose to pool the considerable expertise of the National Oceanography Centre, the Proudman Oceanographic Laboratory and the British Antarctic Survey in order to establish the influence of the Southern Ocean on Equatorial Pacific variability (including ENSO) and to search for observational evidence of ocean planetary wave propagation between the Antarctic and the Equator in response to changes in Antarctic conditions. We will achieve this by using a state-of-the-art numerical ocean model in conjunction with satellite-based observations of sea-ice and sea-surface height and in situ hydrographic data.