Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

El Niño's 'remote control' on hurricanes in the Northeastern Pacific

05.12.2014

El Niño, the abnormal warming of sea surface temperatures in the Pacific Ocean, is a well-studied tropical climate phenomenon that occurs every few years. It has major impacts on society and Earth's climate - inducing intense droughts and floods in multiple regions of the globe.

Further, scientists have observed that El Niño greatly influences the yearly variations of tropical cyclones (a general term which includes hurricanes, typhoons and cyclones) in the Pacific and Atlantic Oceans. However, there is a mismatch in both timing and location between this climate disturbance and the Northern Hemisphere hurricane season:


The discharge of heat, occurring in the boreal summer, followed the peak of El Niño (August-September 1998). Historical tracks of Category 3 to 5 hurricanes that developed after the peak of strong El Niños in 1991/92, 1997/98, 2008/09 and 2014 are shown in black.

Credit: Jin, et al. (2014)

El Niño peaks in winter and its surface ocean warming occurs mostly along the equator, i.e. a season and region without tropical cyclone (TC) activity. This prompted scientists to investigate El Niño's influence on hurricanes via its remote ability to alter atmospheric conditions such as stability and vertical wind shear rather than the local oceanic environment.

Fei-Fei Jin and Julien Boucharel at the University of Hawai'i School of Ocean and Earth Science and Technology (SOEST) and I-I Lin at the National Taiwan University published a paper today in Nature that uncovers what's behind this "remote control."

Jin and colleagues uncovered an oceanic pathway that brings El Niño's heat into the Northeastern Pacific basin two or three seasons after its winter peak - right in time to directly fuel intense hurricanes in that region.

El Niño develops as the equatorial Pacific Ocean builds up a huge amount of heat underneath the surface and it turns into La Niña when this heat is discharged out of the equatorial region.

"This recharge/discharge of heat makes El Niño/La Niña evolve somewhat like a swing," said lead author of the study Jin.

Prior to Jin and colleagues' recent work, researchers had largely ignored the huge accumulation of heat occurring underneath the ocean surface during every El Niño event as a potential culprit for fueling hurricane activity.

"We did not connect the discharged heat of El Niño to the fueling of hurricanes until recently, when we noticed another line of active research in the tropical cyclone community that clearly demonstrated that a strong hurricane is able to get its energy not only from the warm surface water, but also by causing warm, deep water - up to 100 meters deep - to upwell to the surface," Jin continued.

Co-author Lin had been studying how heat beneath the ocean surface adds energy to intensify typhoons (tropical cyclones that occur in the western Pacific).

"The super Typhoon Hainan last year, for instance, reached strength way beyond normal category 5," said Lin. "This led to a proposed consideration to extend the scale to category 6, to be able to grasp more properly its intensity. The heat stored underneath the ocean surface can provide additional energy to fuel such extraordinarily intense tropical cyclones."

"The North-Eastern Pacific is a region normally without abundant subsurface heat," said Boucharel, a post-doctoral researcher at UH SOEST. "El Niño's heat discharged into this region provides conditions to generate abnormal amount of intense hurricanes that may threaten Mexico, the southwest of the US and the Hawaiian islands."

Furthermore, caution the authors, most climate models predict a slow down of the tropical atmospheric circulation as the mean global climate warms up. This will result in extra heat stored underneath the North-eastern Pacific and thus greatly increase the probability for this region to experience more frequent intense hurricanes.

Viewed more optimistically, the authors point out that their findings may provide a skillful method to anticipate the activeness of the coming hurricane season by monitoring the El Niño conditions two to three seasons ahead of potentially powerful hurricane that may result.

The School of Ocean and Earth Science and Technology at the University of Hawaii at Manoa was established by the Board of Regents of the University of Hawai'i in 1988 in recognition of the need to realign and further strengthen the excellent education and research resources available within the University. SOEST brings together four academic departments, three research institutes, several federal cooperative programs, and support facilities of the highest quality in the nation to meet challenges in the ocean, earth and planetary sciences and technologies.

Marcie Grabowski | EurekAlert!
Further information:
http://www.hawaii.edu

More articles from Earth Sciences:

nachricht Colorado River's connection with the ocean was a punctuated affair
16.11.2017 | University of Oregon

nachricht Researchers create largest, longest multiphysics earthquake simulation to date
14.11.2017 | Gauss Centre for Supercomputing

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

Im Focus: Wrinkles give heat a jolt in pillared graphene

Rice University researchers test 3-D carbon nanostructures' thermal transport abilities

Pillared graphene would transfer heat better if the theoretical material had a few asymmetric junctions that caused wrinkles, according to Rice University...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

NASA detects solar flare pulses at Sun and Earth

17.11.2017 | Physics and Astronomy

NIST scientists discover how to switch liver cancer cell growth from 2-D to 3-D structures

17.11.2017 | Health and Medicine

The importance of biodiversity in forests could increase due to climate change

17.11.2017 | Studies and Analyses

VideoLinks
B2B-VideoLinks
More VideoLinks >>>