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 Predicting eruptions using satellites and math
28.06.2017 | Frontiers

nachricht NASA sees quick development of Hurricane Dora
27.06.2017 | NASA/Goddard Space Flight Center

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Extensive Funding for Research on Chromatin, Adrenal Gland, and Cancer Therapy

28.06.2017 | Awards Funding

Predicting eruptions using satellites and math

28.06.2017 | Earth Sciences

Extremely fine measurements of motion in orbiting supermassive black holes

28.06.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>