Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

TRMM satellite proves El Nino holds the reins on global rains

09.11.2004


NASA scientists recently found the El Nino Southern Oscillation (ENSO) is the main driver of the change in rain patterns all around the world.



The NASA and Japan Aerospace Exploration Agency (JAXA) Tropical Rainfall Measuring Mission (TRMM) satellite has enabled scientists to look around the globe and determine where the year-to-year changes in rainfall are greatest. The TRMM is a joint mission between NASA and JAXA designed to monitor and study tropical rainfall.

Researchers Ziad Haddad and Jonathan Meagher of NASA’s Jet Propulsion Laboratory, Pasadena, Calif., Robert Adler and Eric Smith of NASA’s Goddard Space Flight Center, Greenbelt, Md., used TRMM data to identify areas where the year-to-year change in rainfall between 1998 and 2003 was greatest.


By studying the rain patterns in these areas over the past 50 years, with rain gauge data prior to 1998, they established the main component of this change in global rainfall is directly correlated with the El Nino Southern Oscillation. The study appeared in a recent issue of the Journal of Geophysical Research-Atmospheres.

Haddad and his colleagues compared local changes in worldwide rainfall. For years, scientists have known El Nino drastically modifies rainfall patterns in many regions. For example, Indonesia and the Northeastern Amazon basin consistently suffer droughts during El Nino and excessive rains during La Nina. The Southeastern United States and California are typically wetter than usual during El Nino and drier than usual during La Nina.

Scientists also have known several regions with abundant rain are not influenced by the El-Nino/La-Nina changes, including the Bay of Bengal and the vast expanse of the Western Pacific Ocean between the Marshall Islands, Micronesia and the Marianas.

Until the launch of TRMM in 1997, it was impossible to accurately measure change in tropical rainfall patterns, because no instruments were available to record global rainfall. TRMM uses microwave technology to probe through clouds and estimate how much rainfall they are producing. The TRMM data are invaluable over areas where there are no rain gauges, such as the open ocean.

Using TRMM’s measurements, the researchers were able to condense the year-to-year change in rainfall patterns into a single rain-change index. The index is a color-coded map that shows areas of rainfall around the world that are influenced somewhat to greatly, during an ENSO event.

Rainfall data from land and island stations were used to extend this index back in time and to compare it with the ENSO sea-surface temperature and atmospheric pressure. The results showed a strong relationship between the rainfall patterns and ENSO. "The fact that the rain-change index, which comes directly from global measurements, tracks the ENSO indices from the 1950s to the present confirms that El Nino is the principal driver of global year-to-year rainfall change," Haddad said.

NASA plans the Global Precipitation Measurement mission (GPM), a future multi-national multi-satellite mission to expand the scope of TRMM. GPM will focus on producing three- dimensional maps of rain around the world every three hours.

TRMM is the first space-based rain gauge that uses microwaves to see how much precipitation falls from clouds around the tropics. The TRMM satellite’s precipitation radar acts like a highly sensitive microwave camera. It is capable of probing clouds to reveal their vertical structure and precipitation they produce. It has enabled scientists to measure rainfall over the oceans and landmasses with unprecedented accuracy.

Rob Gutro | EurekAlert!
Further information:
http://www.gsfc.nasa.gov

More articles from Earth Sciences:

nachricht Impacts of mass coral die-off on Indian Ocean reefs revealed
21.02.2017 | University of Exeter

nachricht How much biomass grows in the savannah?
16.02.2017 | Friedrich-Schiller-Universität Jena

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

Microhotplates for a smart gas sensor

22.02.2017 | Power and Electrical Engineering

Scientists unlock ability to generate new sensory hair cells

22.02.2017 | Life Sciences

Prediction: More gas-giants will be found orbiting Sun-like stars

22.02.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>