DTN Wednesday 05/13/15
Australia Declares El Nino
The Australia Bureau of Meteorology (BOM) is now on the El Nino bandwagon. The BOM made that announcement this week. Here is part of the BOM bulletin:
The Pacific Ocean analysis meter from the Australia Bureau of Meteorology has moved from an El Nino watch to a full-fledged El Nino. (BOM graphic by Nick Scalise)
"The tropical Pacific is in the early stages of El Nino. Based upon model outlooks and current observations, the Bureau's ENSO Tracker has been raised to El Nino status.
El Nino--Southern Oscillation (ENSO) indicators have shown a steady trend towards El Nino levels since the start of the year. Sea surface temperatures in the tropical Pacific Ocean have exceeded El Nino thresholds for the past month, supported by warmer-than-average waters below the surface. Trade winds have remained consistently weaker than average since the start of the year, cloudiness at the (International) Date Line has increased and the Southern Oscillation Index (SOI) has remained negative for several months. These indicators suggest the tropical Pacific Ocean and atmosphere have started to couple and reinforce each other, indicating El Nino is likely to persist in the coming months.
International climate models surveyed by the Bureau indicate that tropical Pacific Ocean temperatures are likely to remain above El Nino thresholds through the coming southern winter and at least into spring."
An article on the Sydney, Australia Morning Herald newspaper reviewed the BOM announcement, and added some additional detail in an article by Herald environment editor Peter Hannam:
"A "substantial" El Nino event has begun, raising the likelihood of worsening drought over inland Australia and higher daytime temperatures, the Bureau of Meteorology said.
'This will be quite a substantial event,' said David Jones, head of climate monitoring at the bureau. 'It's not a weak one or a near miss' as in 2014, he said. 'This event is perhaps running ahead of where the models had predicted.'...
Abnormally warm sea-surface temperatures have been observed in all five regions of the equatorial Pacific monitored by meteorologists. While the threshold level is 0.8 degrees, all regions were more than one degree above normal -- the first time all weekly values have exceeded such a mark since February 1998, the bureau said.
The 'super El Nino' event of 1997-98 resulted in a spike in global temperatures that set a record that has only been marginally topped in 2005, 2010 and 2014. Climate specialists say El Ninos add 0.1-0.2 degrees to global temperatures, making it likely that 2015 and 2016 may challenge the new high set only last year.
Another criterion for an El Nino is that the normal east-to-west trade winds are weaker than average. In fact, the winds were reversed, blowing eastwards for five days to May 10, in a sign that the atmosphere has 'coupled' with the changes in ocean temperatures, reinforcing them.
A third criterion is that the Southern Oscillation Index--a gauge of pressure differences between Darwin and Tahiti--has persistent readings of at least minus-7. The latest bureau update, shows the SOI dropped to almost minus-10 in the past two weeks.
The final criterion, also reached, is that a majority of the eight major climate models from around the world used by the bureau show continued anomalous warmth in the equatorial Pacific.
In fact, all eight of the international models indicate the central Pacific will warm further in coming months and may be prolonged, the bureau said."
The full announcement from the Australia BOM is is at this link: http://www.bom.gov.au/…
The full article from the Sydney Morning Herald is available here: http://goo.gl/…
Bryce
Twitter @BAndersonDTN
Australia Declares El Nino
The Australia Bureau of Meteorology (BOM) is now on the El Nino bandwagon. The BOM made that announcement this week. Here is part of the BOM bulletin:
The Pacific Ocean analysis meter from the Australia Bureau of Meteorology has moved from an El Nino watch to a full-fledged El Nino. (BOM graphic by Nick Scalise)
"The tropical Pacific is in the early stages of El Nino. Based upon model outlooks and current observations, the Bureau's ENSO Tracker has been raised to El Nino status.
El Nino--Southern Oscillation (ENSO) indicators have shown a steady trend towards El Nino levels since the start of the year. Sea surface temperatures in the tropical Pacific Ocean have exceeded El Nino thresholds for the past month, supported by warmer-than-average waters below the surface. Trade winds have remained consistently weaker than average since the start of the year, cloudiness at the (International) Date Line has increased and the Southern Oscillation Index (SOI) has remained negative for several months. These indicators suggest the tropical Pacific Ocean and atmosphere have started to couple and reinforce each other, indicating El Nino is likely to persist in the coming months.
International climate models surveyed by the Bureau indicate that tropical Pacific Ocean temperatures are likely to remain above El Nino thresholds through the coming southern winter and at least into spring."
An article on the Sydney, Australia Morning Herald newspaper reviewed the BOM announcement, and added some additional detail in an article by Herald environment editor Peter Hannam:
"A "substantial" El Nino event has begun, raising the likelihood of worsening drought over inland Australia and higher daytime temperatures, the Bureau of Meteorology said.
'This will be quite a substantial event,' said David Jones, head of climate monitoring at the bureau. 'It's not a weak one or a near miss' as in 2014, he said. 'This event is perhaps running ahead of where the models had predicted.'...
Abnormally warm sea-surface temperatures have been observed in all five regions of the equatorial Pacific monitored by meteorologists. While the threshold level is 0.8 degrees, all regions were more than one degree above normal -- the first time all weekly values have exceeded such a mark since February 1998, the bureau said.
The 'super El Nino' event of 1997-98 resulted in a spike in global temperatures that set a record that has only been marginally topped in 2005, 2010 and 2014. Climate specialists say El Ninos add 0.1-0.2 degrees to global temperatures, making it likely that 2015 and 2016 may challenge the new high set only last year.
Another criterion for an El Nino is that the normal east-to-west trade winds are weaker than average. In fact, the winds were reversed, blowing eastwards for five days to May 10, in a sign that the atmosphere has 'coupled' with the changes in ocean temperatures, reinforcing them.
A third criterion is that the Southern Oscillation Index--a gauge of pressure differences between Darwin and Tahiti--has persistent readings of at least minus-7. The latest bureau update, shows the SOI dropped to almost minus-10 in the past two weeks.
The final criterion, also reached, is that a majority of the eight major climate models from around the world used by the bureau show continued anomalous warmth in the equatorial Pacific.
In fact, all eight of the international models indicate the central Pacific will warm further in coming months and may be prolonged, the bureau said."
The full announcement from the Australia BOM is is at this link: http://www.bom.gov.au/…
The full article from the Sydney Morning Herald is available here: http://goo.gl/…
Bryce
Twitter @BAndersonDTN
Comment