There have been questions from some in the 2010 SHTP fleet regarding the effect of the current El Nino/Southern Oscillation (ENSO) on potential racing conditions in the Eastern Pacific (EPAC)
During El Niño(ENSO) episodes, such as occured in late 2009/early 2010, lower than normal atmospheric pressure was observed over the EPAC. In addition, warmer than average sea surface temps were found in the EPAC, giving rise to enhanced rainfall such as we had in California this winter. This pattern of lower pressure and warmer sea temps is associated with weaker than normal east to west trade winds IF it were occuring during summer months.
Which it is not. By all measurements and models, the 2009/2010 El Nino (ENSO) dissipated in May, 2010. Average sea surface temperature anomalies have declined and are currently going negative, leading to potential La Nina conditions later this year. Weather professionals are describing weather this June/July over the EPAC as "ENSO-neutral."
What this means for the SHTP fleet is cooler ocean temps and a reduction of chances of encountering tropical storms, as they will be fewer and track further south than during an El Nino event.
It also means NE tradewinds should be of average strength, 13-18 knots, with an average night time encounter of 2-5 squalls during the last third of the race. The winds in these squalls typically average 10 knots above ambient tradewind strength, and the average squall wind direction is 20 degrees further to the (right) East.
As a reference, the current sea surface temperature on June 8, 2010 at "Pt. B," 100 miles NE of Kauai, is 75 degrees. There has so far been one named tropical storm, "AGATHA," which came ashore into southern Mexico/Guatemala on May 29, producing devastating floods and wind speeds of 40 knots. Currently, today, June 11, 2010, there is no tropical storm activity in the EPAC.
During El Niño(ENSO) episodes, such as occured in late 2009/early 2010, lower than normal atmospheric pressure was observed over the EPAC. In addition, warmer than average sea surface temps were found in the EPAC, giving rise to enhanced rainfall such as we had in California this winter. This pattern of lower pressure and warmer sea temps is associated with weaker than normal east to west trade winds IF it were occuring during summer months.
Which it is not. By all measurements and models, the 2009/2010 El Nino (ENSO) dissipated in May, 2010. Average sea surface temperature anomalies have declined and are currently going negative, leading to potential La Nina conditions later this year. Weather professionals are describing weather this June/July over the EPAC as "ENSO-neutral."
What this means for the SHTP fleet is cooler ocean temps and a reduction of chances of encountering tropical storms, as they will be fewer and track further south than during an El Nino event.
It also means NE tradewinds should be of average strength, 13-18 knots, with an average night time encounter of 2-5 squalls during the last third of the race. The winds in these squalls typically average 10 knots above ambient tradewind strength, and the average squall wind direction is 20 degrees further to the (right) East.
As a reference, the current sea surface temperature on June 8, 2010 at "Pt. B," 100 miles NE of Kauai, is 75 degrees. There has so far been one named tropical storm, "AGATHA," which came ashore into southern Mexico/Guatemala on May 29, producing devastating floods and wind speeds of 40 knots. Currently, today, June 11, 2010, there is no tropical storm activity in the EPAC.
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