Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

NASA Satellite Finds an Unusually Tall Storm-cell in Cyclone Evan

20.12.2012
NASA's Tropical Rainfall Measuring Mission or TRMM satellite found an unusually tall towering thunderstorm in Cyclone Evan.

According to Owen Kelley of the TRMM satellite team at NASA's Goddard Space Flight Center in Greenbelt, Md, the most startling feature of the December 16 overflight of Tropical Cyclone Evan was the extremely tall storm-cell in the north side of the eyewall. At the time TRMM passed overhead and captured an image of the storm, Evan was about to rake across the northern coast of the islands of Fiji.


TRMM captured data on Cyclone Evan's cloud heights and rainfall on Dec. 16 and spotted an extremely tall storm-cell in the north side of the eyewall. The updrafts in this tower extended high enough to lift precipitation-size ice 17 km above the ocean surface (red in the image). The insert shows the infrared cloud top temperatures. The clockwise arrow shows the direction of the winds circling the eyewall. At the north side of the eyewall, the explosive circular shape is the upper-level outflow from the extremely tall tower, Credit: NASA/Owen Kelley

The updrafts in this tower extended high enough to lift precipitation-size ice 17 km (10.5 miles) above the ocean surface. Tall precipitation cells are generally taken to be anything at least 14.5 km (9 miles) high and are nicknamed "hot towers," but what was seen in Evan's eyewall was a different category of storm cell.

Storm-cells as tall as the one in the eyewall of Evan have been long known to occur occasionally over land, but before the TRMM satellite, there were not thought to occur over ocean far from land. While field campaigns have periodically studied one location or other over the ocean, what TRMM has taught us is that such sporadic observations are insufficient if you want catch rare events. After 15 years of continuous operation, TRMM satellite reveals the rare features and challenges our understanding of how the weather works. The ocean is an unlikely place to find extremely tall oceanic cells because the ocean surface stays roughly constant in temperature, unlike the land which quickly heats up over the course of a day, increasing low-level instability, and encouraging tall cells to form.

During the first 10 years of the TRMM mission, only 5 thunderstorm cells as tall as the one seen in cyclone Evan were observed in South Pacific tropical cyclones. Due to their rarity, perhaps these 17-km-tall (10.5 mile) cells deserve their own nickname. To distinguish them from run-of-the-mill hot towers, one can call these cells "titans," "super towers," or just extremely tall.

Over all of the tropical oceans, only 174 such extremely tall cells were observed during the first 10 years of TRMM (1). That's 174 extremely tall cells out of the approximately 9 million oceanic storms that TRMM saw during that time. It is worth noting however, that even TRMM has its limitations. It does not observe the whole earth continuously and frequently misses short-lived events. With this in mind, these extremely tall cells most likely occur more often than TRMM observes them although they do make up a very small fraction of the ocean's weather.

TRMM also observed cloud top temperatures. At the north side of the eyewall, was the upper-level outflow from the extremely tall tower, i.e. the tower's "exhaust fumes." The exhaust moves outward horizontally in every direction, including toward the eye at the center of the tropical cyclone. It is through a process called "forced subsidence" that the exhaust from eyewall towers may warm the air in the tropical cyclone's eye. Warming the air in the eye lowers the surface pressure and encourages intensification of the winds circling the eye.

The TRMM satellite is a joint mission between the United States and Japan.

Text Credit: Owen Kelley
NASA's Goddard Space Flight Center

Owen Kelley | EurekAlert!
Further information:
http://www.nasa.gov
http://www.nasa.gov/mission_pages/hurricanes/features/evan-stormcell.html

More articles from Earth Sciences:

nachricht Low sea-ice cover in the Arctic
13.09.2019 | Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung

nachricht A precise chemical fingerprint of the Amazon
12.09.2019 | Harvard John A. Paulson School of Engineering and Applied Sciences

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: The working of a molecular string phone

Researchers from the Department of Atomically Resolved Dynamics of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg, the University of Potsdam (both in Germany) and the University of Toronto (Canada) have pieced together a detailed time-lapse movie revealing all the major steps during the catalytic cycle of an enzyme. Surprisingly, the communication between the protein units is accomplished via a water-network akin to a string telephone. This communication is aligned with a ‘breathing’ motion, that is the expansion and contraction of the protein.

This time-lapse sequence of structures reveals dynamic motions as a fundamental element in the molecular foundations of biology.

Im Focus: Milestones on the Way to the Nuclear Clock

Two research teams have succeeded simultaneously in measuring the long-sought Thorium nuclear transition, which enables extremely precise nuclear clocks. TU Wien (Vienna) is part of both teams.

If you want to build the most accurate clock in the world, you need something that "ticks" very fast and extremely precise. In an atomic clock, electrons are...

Im Focus: Graphene sets the stage for the next generation of THz astronomy detectors

Researchers from Chalmers University of Technology have demonstrated a detector made from graphene that could revolutionize the sensors used in next-generation space telescopes. The findings were recently published in the scientific journal Nature Astronomy.

Beyond superconductors, there are few materials that can fulfill the requirements needed for making ultra-sensitive and fast terahertz (THz) detectors for...

Im Focus: Physicists from Stuttgart prove the existence of a supersolid state of matte

A supersolid is a state of matter that can be described in simplified terms as being solid and liquid at the same time. In recent years, extensive efforts have been devoted to the detection of this exotic quantum matter. A research team led by Tilman Pfau and Tim Langen at the 5th Institute of Physics of the University of Stuttgart has succeeded in proving experimentally that the long-sought supersolid state of matter exists. The researchers report their results in Nature magazine.

In our everyday lives, we are familiar with matter existing in three different states: solid, liquid, or gas. However, if matter is cooled down to extremely...

Im Focus: World record for tandem perovskite-CIGS solar cell

A team headed by Prof. Steve Albrecht from the HZB will present a new world-record tandem solar cell at EU PVSEC, the world's largest international photovoltaic and solar energy conference and exhibition, in Marseille, France on September 11, 2019. This tandem solar cell combines the semiconducting materials perovskite and CIGS and achieves a certified efficiency of 23.26 per cent. One reason for this success lies in the cell’s intermediate layer of organic molecules: they self-organise to cover even rough semiconductor surfaces. Two patents have been filed for these layers.

Perovskite-based solar cells have experienced an incredibly rapid increase in efficiency over the last ten years. The combination of perovskites with classical...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Society 5.0: putting humans at the heart of digitalisation

10.09.2019 | Event News

Interspeech 2019 conference: Alexa and Siri in Graz

04.09.2019 | Event News

AI for Laser Technology Conference: optimizing the use of lasers with artificial intelligence

29.08.2019 | Event News

 
Latest News

Low sea-ice cover in the Arctic

13.09.2019 | Earth Sciences

Researchers produce synthetic Hall Effect to achieve one-way radio transmission

13.09.2019 | Power and Electrical Engineering

Penn engineers' new topological insulator reroutes photonic 'traffic' on the fly

13.09.2019 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>