Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Data-driven tools cast geographical patterns of rainfall extremes in new light

20.12.2011
Using statistical analysis methods to examine rainfall extremes in India, a team of researchers has made a discovery that resolves an ongoing debate in published findings and offers new insights.

The study, initiated by Auroop Ganguly and colleagues at Oak Ridge National Laboratory, reports no evidence for uniformly increasing trends in rainfall extremes averaged over the entire Indian region. It does, however, find a steady and significant increase in the spatial variability of rainfall extremes over the region.

These findings, published in Nature Climate Change, are contrary to results of some earlier work on this subject. The new study uses statistical methods designed explicitly for modeling extreme values and associated uncertainties.

"Our research suggests that one needs to be aware of the different characterizations of extremes and that these characterizations require both interpretability and statistical rigor," said Ganguly, now a faculty member at Northeastern University in Boston.

In addition, it makes sense to look at local and regional drivers such as urbanization and deforestation in addition to global scale issues. Although this study focused on rainfall variability in India, the same methodology can be applied to any region of the world, Ganguly said.

Ganguly and co-authors Subimal Ghosh (Indian Institute of Technology Bombay, Debasish Das (Temple University) and Shih-Chieh Kao (ORNL) used their statistical methodologies to analyze data from 1,803 stations from 1951 to 2003. This information was provided in 1-by-1-degree spatial grids by the India Meteorological Department.

The research team noted that statistical observations offer complementary insights compared to the current generation of physics-based computational models. This is especially the case if the goal is to understand climate and rainfall variability at local to regional scales.

Understanding climate model-simulated trends of precipitation extremes and developing metrics relevant for water resources decisions were the focus of a paper published earlier this year in the Journal of Geophysical Research. In that paper, Ganguly and co-author Kao showed that while models provide relatively credible predictive insights of precipitation extremes at aggregate spatial scales, the uncertainty begins to increase significantly at localized spatial scales - especially over the tropical regions.

"Even as higher resolution models are attempting to get to the stage where spatially explicit insights can be generated, the kind of insights generated from observations in this study can be used as methods for model diagnostics and can help address science gaps," Kao said.

Ganguly noted that the Nature Climate Change paper, titled "Lack of uniform trends but increasing spatial variability in observed Indian rainfall extremes," is the result of a team effort with researchers from diverse disciplines. Ghosh, the first author, is a hydro-climate scientist and civil engineer; Das is a graduate student in computer science and data mining; Kao is a statistical who specializes in water availability and flood frequency analysis; and Ganguly, a civil engineer, specializes in climate extremes and water sustainability as well as data sciences for complex systems.

This research concept was initiated when all the authors were working with Ganguly at ORNL and was funded by the Laboratory Directed Research and Development program. The National Science Foundation's Expeditions in Computing program and the Department of Science and Technology of India also provided funding.

UT-Battelle manages ORNL for the Department of Energy's Office of Science.

Ron Walli | EurekAlert!
Further information:
http://www.ornl.gov

More articles from Earth Sciences:

nachricht Live from the ocean research vessel Atlantis
13.12.2018 | National Science Foundation

nachricht NSF-supported scientists present new research results on Earth's critical zone
13.12.2018 | National Science Foundation

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Data use draining your battery? Tiny device to speed up memory while also saving power

The more objects we make "smart," from watches to entire buildings, the greater the need for these devices to store and retrieve massive amounts of data quickly without consuming too much power.

Millions of new memory cells could be part of a computer chip and provide that speed and energy savings, thanks to the discovery of a previously unobserved...

Im Focus: An energy-efficient way to stay warm: Sew high-tech heating patches to your clothes

Personal patches could reduce energy waste in buildings, Rutgers-led study says

What if, instead of turning up the thermostat, you could warm up with high-tech, flexible patches sewn into your clothes - while significantly reducing your...

Im Focus: Lethal combination: Drug cocktail turns off the juice to cancer cells

A widely used diabetes medication combined with an antihypertensive drug specifically inhibits tumor growth – this was discovered by researchers from the University of Basel’s Biozentrum two years ago. In a follow-up study, recently published in “Cell Reports”, the scientists report that this drug cocktail induces cancer cell death by switching off their energy supply.

The widely used anti-diabetes drug metformin not only reduces blood sugar but also has an anti-cancer effect. However, the metformin dose commonly used in the...

Im Focus: New Foldable Drone Flies through Narrow Holes in Rescue Missions

A research team from the University of Zurich has developed a new drone that can retract its propeller arms in flight and make itself small to fit through narrow gaps and holes. This is particularly useful when searching for victims of natural disasters.

Inspecting a damaged building after an earthquake or during a fire is exactly the kind of job that human rescuers would like drones to do for them. A flying...

Im Focus: Topological material switched off and on for the first time

Key advance for future topological transistors

Over the last decade, there has been much excitement about the discovery, recognised by the Nobel Prize in Physics only two years ago, that there are two types...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

ICTM Conference 2019: Digitization emerges as an engineering trend for turbomachinery construction

12.12.2018 | Event News

New Plastics Economy Investor Forum - Meeting Point for Innovations

10.12.2018 | Event News

EGU 2019 meeting: Media registration now open

06.12.2018 | Event News

 
Latest News

Data use draining your battery? Tiny device to speed up memory while also saving power

14.12.2018 | Power and Electrical Engineering

Tangled magnetic fields power cosmic particle accelerators

14.12.2018 | Physics and Astronomy

In search of missing worlds, Hubble finds a fast evaporating exoplanet

14.12.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>