Saturday, June 11, 2011

Outrageous Weather!

Whether it is blazing heat, to tornado outbreaks (in Massachusetts no less!), mass flooding, to devastating wildfires...If I did not think otherwise, I would think the world is coming to an end? Perhaps people were correct to think that Apocalypse or Judgement Day was beginning May 21st just last month. All religion aside, in fact it is  climatology to blame for this one.

So far this year, the weather has cost the U.S. billions of dollars in storm related damages making it a new records for the most high-cost weather events according to government records and insurance estimates...and the year is only half over...AND the hurricane season just underway...

From the latest reports from the Climate Prediction Center; ENSO (El Nino- Southern Oscillation)- neutral conditions have developed and been occurring since this past May (2011) and are expected to continue in the Northern Hemisphere through the Summer (2011).
To refresh the memory, ENSO is considered to be a quasiperiodic (occurring in an irregular periodic pattern) climate pattern that occurs across the tropical area of the Pacific Ocean approximately every five years. Scientists can find these patterns by observing variations in sea surface temperature (sst) in the eastern tropical Pacific Ocean, surface air pressure in the western tropical Pacific Ocean. El Nino is commonly known as the "warm oceanic phase." Typically ENSO can assist in more strong weather events
The transition from La Nina to ENSO- neutral conditions occurred in May through indications of sea surface temperature anomalies from the equatorial Pacific Ocean through east of the International Date Line:  showing near-average SSTs in the central and east-central equatorial Pacific and above-average SSTs in the eastern equatorial Pacific. Although the ocean temperatures are showing more of a transition to ENSO, the atmospheric circulation anomalies are still indicating La Nina; weaker and low surface air pressure.

ENSO- neutral. Courtesy of Wikipedia
Referring to the image above: This image is a slice of the ocean. The colors represent the SST with red being the warmest temperature. The warming water (the bright red) is pushed towards the west side of the Pacific as the colder water is pulled up along the west coast of South America. Considering this, one could read the image and see that the SST is warmer to the west. A thermocline is more or less a 'cap' of warm water.. it inhibits mixing and allows for the water to warm near the surface. This thermocline is not good for the fishing industry simply because there is no nutrients to the water er-go there is no fish. The equatorial winds warm as they flow west across the Pacific allowing for convection to occur (the circulation of rising warm air). This allows for hot air to rise in the western Pacific and flows it eastward to cool descending air into South America.

Winds also play a pretty big role in the oscillations. As of late, the reports have suggested rather anomalous low-level easterly and upper-level westerly winds weakening but have have been quite persistent over the central Pacific Ocean. Altogether between the findings from the atmospheric and oceanic measurements, all is pointing towards a transition  or change of the pattern to ENSO-neutral conditions...keep in mind that some impacts form La Nina are still present and could be for the next month or for the rest of the summer in the global Tropics in the Northern Hemisphere.
Through reading the reports, this forecast is just a preliminary forecast to try to get a better understanding on the weather and climate to come for next few months. In particular, to try to get a better understanding of how this years hurricane season will play out.

Forecasters at the National Hurricane Center (NHC) have already predicted this season to be a rather active one. Along with the ENSO-neutral conditions, SST over the tropical Atlantic Ocean and Caribbean Sea (also known as the Main Development Region) are above-average, especially this early in the season (June 1st was the first day of the hurricane season). Water temperatures off the coast of NJ alone are already flirting with the 70s! We are talking about at earliest late July water temperatures. Hurricanes and tropical storms thrive off of warm waters.  Past hurricane seasons (climatology) has shown that these conditions explained above have produced a rather active Atlantic hurricane season. If this plays out, it will not be a good situation for the east coast...especially the already awfully eroded New Jersey beaches.
The NHC is forecasting a comparable active season in the Atlantic since 1995. The following estimates are a 70% probability for each of the ranges of activity for this 2011 season:

  • 12-18 Named Storms,
  • 6-10 Hurricanes
  • 3-6 Major Hurricanes
  • An ACE range of 105%-200% of the 1981-2010 median. (NHC)

Here's to a beautiful hurricane season! Hopefully we don't see a Cat. 3 make its way into NYC...(I will discuss what could happen in the next few posts).

Next discussion: The Midwest Flooding, devastating tornadoes, record breaking heat, the southwest wildfires;  is there a link?