Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

NASA scientists take first ’full-body scan’ of evolving thunderstorm

16.01.2003



A doctor gets a better view inside a patient by probing the body with CAT and MRI scanning equipment. Now, NASA meteorologists have done a kind of "full-body scan" of an evolving thunderstorm in the tropics, using advanced radar equipment to provide a remarkable picture of the storm’s anatomy. The observations are expected to help double-check satellite rainfall measurements, improve computer models of storms, and make the skies safer for airplanes to navigate.

David Atlas of NASA’s Goddard Space Flight Center, Greenbelt, Md., has gathered the data collected from an unusual storm over the Amazon rainforest in February 1999 and arranged it into an intriguing image of the storm clouds’ inner workings.

The research, co-authored by University of Colorado’s Christopher Williams, appears in the January 2003 American Meteorological Society’s Journal of the Atmospheric Sciences.



Storms often form precipitation in one of two ways, either by forming rain at lower altitudes or by forming frozen particles higher in the atmosphere. But this storm was unusual in that both processes operated as the storm evolved.

In the tropics, the air is warm even at considerably high altitudes, so rain can occur in high clouds by forming liquid droplets without freezing first. During the warm rain stage only the larger drops fall quickly enough to overcome the strength of the updraft, but the smaller ones are carried very high into the clouds, where they freeze into snow and hail. This storm possessed a very strong updraft and also formed frozen precipitation in its upper levels even as rain fell closer to the ground.

"While such a two-phase process should occur in many vigorous storms, it has rarely been observed in a single storm," Atlas said.

"The ’full-body scan’ also provides new insight into the intensity and hazards within storms, which should be avoided by aircraft. Even the aircraft used in this study did not go into the core of the storm because of the hazards," Atlas said.

At the higher altitudes, cold temperatures created larger frozen particles that were able to fall through the updraft. The smaller ones continued to rise, colliding with the larger falling ones. These collisions caused friction and electrical charges that generated lightning.

Radar was the primary means by which the "body scan" was taken. A team of scientists from NASA, the National Oceanic and Atmospheric Administration (NOAA), the National Center for Atmospheric Research (NCAR), and other universities used radar equipment sensitive enough to detect the different kinds of particles from the storm’s base up to its top, some 14 km (8.7 miles) above the jungle floor.

Different types of radar examined different aspects of the storm. These included a scanning Doppler radar, often seen on television weather broadcasts, but specially designed with the capability to measure particle types and sizes and rain rates, provided by NCAR; and a vertically oriented Doppler radar, which measures particle motion and size, and vertical air motions, supplied by NOAA. The analysis was also greatly aided by measurements within the storm made by a jet aircraft operated by the University of North Dakota. NASA provided funds for the use of the two radars and the operation of the jet aircraft during this field experiment."

One purpose of the study was to validate the Tropical Rainfall Measuring Mission (TRMM) satellite measurements. Satellites like TRMM provide data about how these storms operate and help atmospheric scientists better understand how wind circulates above the planet. A continuous array of these evolving tropical thunderstorms around the world acts as a heat engine that warms the upper atmosphere. That warming maintains a gradient of temperature and pressure from the tropics to the poles, and driving the global wind circulation.

"Our particular study attempted to validate what the satellites were showing us with an up-close view," Atlas said. The validation of TRMM data will help to fine-tune and set the stage for the Global Precipitation Mission (GPM) satellite, which is planned to succeed TRMM.

This research was funded in part by NASA’s Tropical Rainfall Measuring- Mission.

Rob Gutro | EurekAlert!
Further information:
http://www.gsfc.nasa.gov/topstory/20021215convective.html

More articles from Earth Sciences:

nachricht NASA eyes Pineapple Express soaking California
24.02.2017 | NASA/Goddard Space Flight Center

nachricht 'Quartz' crystals at the Earth's core power its magnetic field
23.02.2017 | Tokyo Institute of Technology

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

Stingless bees have their nests protected by soldiers

24.02.2017 | Life Sciences

New risk factors for anxiety disorders

24.02.2017 | Life Sciences

MWC 2017: 5G Capital Berlin

24.02.2017 | Trade Fair News

VideoLinks
B2B-VideoLinks
More VideoLinks >>>