Tag Archives: La Nina

Subdued 2016 Tropical Cyclone Activity so far in the Northern Hemisphere

A bit more than two weeks into the 2016 Northern Hemisphere summer we have three-named storms active over the larger Pacific Ocean basin, plus one tropical wave moving westward in the middle of hurricane alley in the Atlantic.

A tropical wave moves westward toward the Caribbean along 'hurricane alley'. Satellite images from NOAA on 07072016 using infrared filter
A tropical wave moves westward toward the Caribbean along ‘hurricane alley’. Satellite images from NOAA on 07072016 using infrared filter

Hurricane BLAS and AGATHA, now a tropical depression, are moving westward some 2000 kilometers east of the Big Island in Hawaii, while category 5 typhoon NEPARTAK, now weakening somewhat, is approaching landfall on the east coast of Taiwan over in the West Pacific on this Thursday 7 July 2016.

NOAA GOES satellite image of 07072016 showing Hurricane BLAS moving over the eastern Pacific approximately 2000 kilometers east of Hawaii
NOAA GOES satellite image of 07072016 showing Hurricane BLAS moving over the eastern Pacific approximately 2000 kilometers east of Hawaii

Tropical cyclone activity so far in 2016 in the northern hemisphere has been somewhat subdued in terms of actual cyclogenesis when compared to recent years.  As of today, Thursday 7 July 2016,  there have been 11 named tropical cyclones worldwide in the northern hemisphere compared to 19 during the same period in 2015. Three of the 2016 storms have only been generated over the past couple of days. The only basin that is a bit more active so far in 2016 versus 2015 is the northern Atlantic, which actually saw its first name tropical cyclone,  Alex, in January of this year, which ended up winding over the central North Atlantic and eventually impacting Greenland.

Satellite image [NOAA} of 07072016 showing Typhoon NEPARTAK approaching landfall on the east coast of Taiwan
Satellite image [NOAA} of 07072016 showing Typhoon NEPARTAK approaching landfall on the east coast of Taiwan
In my opinion, most of this change in tropical cyclone activity so far in 2016 may be attributed to the current neutral El Niño  conditions over the central to eastern Pacific near the equator, after a strong ENSO (El Niño Southern Oscillation) anomaly in 2015 and earlier this year.  Sea-surface temperatures (SST) at the equator are somewhat cooler than average in the central-to-eastern Pacific Ocean. Conditions are looking favorable for the development of La Niña during this 2016 summer in the Northern Hemisphere, perhaps by the fall and the 2016-2017 winter.

There were a total of sixty-six named tropical cyclones plus eleven tropical depressions in the Northern Hemisphere during 2015. Only time will tell how many named storms we will have in 2016, and which basin will see above or below average seasons this year.

Historically La Niña years have brought increased cyclogenesis over the northern Atlantic basin, and the forecast from the National Hurricane Center and others that have issued predictions calls for a somewhat above average 2016 Atlantic Hurricane season.

All interest in and around the Atlantic basin should pay attention,  remain alert, be prepared, and mitigate!

The PACIFIC: what’s in a name?

Recent view of the Pacific Ocean from the International Space Station. Although plenty un thunderheads and storm clouds are seen aloft, we can also glimpse the so-called 'peaceful' ocean as the setting sun reflects upon its surface through a clearing in the clouds
Recent view of the Pacific Ocean from the International Space Station. Although plenty of thunderheads and storm clouds are seen aloft, we can also glimpse the so-called ‘peaceful’ ocean as the setting sun reflects upon its surface through a clearing in the clouds

The Pacific Ocean with a total area of 166.2 Million km² covers about 46% of the Earth’s surface, and reaches the deepest point at 11,033 m below water, which is enough to submerge Mount Everest or Mount K2 by more than 2,000 m.

Elevation map of the Pacific Ocean (USGS-NASA) based on satellite remote sensing observations
Elevation map of the Pacific Ocean (USGS-NASA) based on satellite remote sensing observations

When this magnificent Ocean was first sighted by Europeans in 1513 through the eyes of Vasco Nuñez de Balboa, after having crossed the isthmus of Panama he named it “El Mar del Sur” – ‘The Southern Sea’, because he was facing in that direction.

Map of the Pacific Ocean, "The Southern Sea', by Abraham Ortelius (1589), a royal cartographer for the court of Phlip II of Spain clearly showing the American continent separating the Atlantic from the Pacific
Map of the Pacific Ocean, “The Southern Sea’, by Abraham Ortelius (1589), a royal cartographer for the court of Phlip II of Spain clearly showing the American continent separating the Atlantic from the Pacific

Eight years later, the Portuguese explorer Ferdinand Magellan sailing on a world circumnavigation expedition, to discover new trade routes and new worlds for Europe,  named this ‘Southern Sea’ “el Mar PacÍfico” or ‘The Pacific”, ‘The Peaceful Sea’  after rounding Cape Horn, at the tip of South America, under terrible stormy weather and huge seas where three oceans collide, and finding calm seas as he entered what is now known as ‘The Pacific Ocean”.

Is it really ‘peaceful’ and ‘pacific’, this ocean we are referring to? I really thought so the first time my wife and I flew around its northern fringes on our way from California to Japan. This impression was confirmed when I first flew from Los Angeles to Hawaii on a calm November afternoon and I could hardly see a ripple  on the peaceful Pacific waters below until our big jet descended for a landing  at Honolulu International. Peaceful indeed!

But that perspective of peacefulness has changed as my work related to tropical cyclones has progressed. Now I know that, as an average, based on a historical record going back over 150 years, more than 47% of all tropical cyclones worldwide are generated in some corner of the Pacific Ocean on an annual basis, and also some of the most violent storms.

While the eastern east Pacific sub-basin, off the coasts of Mexico and Central America, seems to generate quite a bit of cyclonic activity year in and year out, it is the far northwestern Pacific, starting over the central Pacific and the Philippines Sea, and moving over the south China Sea and the Yellow Sea, that really generate a large number of tropical cyclones every year, certainly a much more than any other cyclogenesis sub-basin in the world.

Water-vapor satellite image (JTWC) of the northwestern Pacific Ocean showing Tropical Storm RAMMASUN aiming for the Philippines
Water-vapor satellite image (JTWC) of the northwestern Pacific Ocean showing Tropical Storm RAMMASUN aiming for the Philippines

Currently we have tropical storm RAMMASUN  over the western Pacific moving in the general direction of Manila, capital of the Philippines.  And, in the same neighborhood we just recently had Super-typhoon NEOGURIS affecting Taiwan and Japan just last week.

Projected track of current Tropical Storm RAMMASUN on 13 July 2014
Projected track of current Tropical Storm RAMMASUN on 13 July 2014

Farther to the east of this cyclonic activity, near the coast of southern Mexico and Central America, we see the entire region from northern South America and Panama all the way up to just south of the Baja California peninsula populated by a persistent ensemble of tropical waves and disturbed weather cells, the norm in recent years, which has already contributed to generating five named-tropical cyclones in the 2014 east Pacific Hurricane Season that only started on 15 May.

Color-enhanced infrared satellite image (NOAA) of the eastern Pacicifc Ocean, north of the equator, showing the ensemble of tropical waves and storm cells that persist over the region on 13 July 2014
Color-enhanced infrared satellite image (NOAA) of the eastern Pacicifc Ocean, north of the equator, showing the ensemble of tropical waves and storm cells that persist over the region on 13 July 2014

So much for being named PACIFIC, for a basin that generates so much cyclonic activity year after year. A region that also triggers major natural factors such as ENSO, El Niño Southern Oscillation and La Niña, the Madden-Julian Oscillation, and the Pineapple Express that influence so much of the North American weather and also have a mostly dampening effect on cyclogenesis in the Atlantic basin.

It would appear, empirically at least, that as the effects of global warming have continued to be felt and the heat energy content of the Pacific Ocean increases proportionally, together with the capacity of the atmosphere for retaining moisture, the potential for cyclogenesis across this large basin has also kept pace.

Only time will tell, but based on my own observations over the past 25 years or so, the name of Pacific is a misnomer at best for this large and wonderful ocean.

The Pacific: what’s in a name?