Nav: Home

Monsoon mission: A better way to predict Indian weather?

September 28, 2015

To better understand global weather patterns and increase scientific collaboration between the U.S. and India, researchers supported by the Office of Naval Research (ONR) have completed a month-long cruise studying summer monsoon conditions in the Bay of Bengal.

Summer, or southwest, monsoons are moisture-soaked seasonal winds that bring critical rainfall to the Indian subcontinent during the June-September wet season. An abundant season provides sustaining rainfall that replenishes water reservoirs and reaps bountiful crop harvests. By contrast, a weak season could lead to drought, soaring food prices and a battered economy.

"This research will lead to an improved understanding and prediction of the ocean and atmosphere," said Dr. Frank Herr, who heads ONR's Ocean Battlespace Sensing Department. "It also enables ONR to test new and innovative oceanography technology, as well as develop stronger partnerships with Indian scientists."

Incomplete knowledge of the dynamics of monsoons makes it difficult to accurately predict the onset, strength and intraseasonal variations in the monsoon season. ONR's collaborative research will gather data to help improve and refine the forecasting of these winds.

"The predictability of ocean weather is very important to the Navy's global operations and the safety of ships at seas," said ONR Program Manager Dr. Terri Paluszkiewicz. "Fundamental studies of monsoon air-sea interaction are crucial for better weather and climate prediction for the entire global community."

Led by Dr. Amit Tandon, an engineering professor at the University of Massachusetts Dartmouth, approximately 25 American and Indian scientists worked aboard the research vessel R/V Roger Revelle, which is operated by the Scripps Institution of Oceanography under a charter agreement with ONR. Another team of Indian and U.S. scientists on the Indian research vessel Sagar Nidhi worked jointly with those on the Roger Revelle.

Tandon's team studied the uppermost layer of the Bay of Bengal--which is part of the Indian Ocean and a region of monsoon formation. Although the bay is composed of salt water, large amounts of fresh water from rivers and rainstorms dump into it regularly.

"The layer of relatively less salty water near the surface responds rapidly and dramatically to solar heating and nighttime cooling," said Tandon. "It regulates moisture supply to the atmosphere and can trap the sun's heat beneath the surface of the water, releasing it into the air weeks, or even months, later--increasing the power of a monsoon."

The researchers used wirewalkers (wave-powered vehicles that can sample water at various depths), buoys, gliders and towed platforms--equipped with data-collecting sensors--to compile information about the Bay of Bengal's water and air temperature, atmospheric moisture, and mixtures and movements of fresh and salt water--all factors contributing to monsoon activity.

"Our field study has mapped out the upper ocean structure of the north Bay of Bengal in unprecedented detail, with cutting-edge oceanography instrumentation, some of which is being used for the first time," said Tandon.

With this research complete, U.S. and Indian scientists will now analyze the cruise data, in the hopes of eventually designing a computer forecasting model to accurately predict future monsoon formation.

Monsoon research aligns with several tenets of the Cooperative Strategy for 21st Century Seapower, a maritime strategy shared by the U.S. Navy, Marine Corps and Coast Guard. The strategy calls for increased focus on battlespace awareness, which includes surveillance, intelligence gathering and greater knowledge about the environments in which warfighters operate.
-end-


Office of Naval Research

Related Monsoon Articles:

The Asian summer monsoon -- a smokestack to the Northern Hemisphere stratosphere
The formation of Asian tropopause aerosol layer is considered to be caused by the Asian summer monsoon, which effectively pumps the Asian pollutants to the upper troposphere and lower stratosphere, leading to enhanced aerosol formation.
Bangladesh's heavy rainfall examined with NASA's IMERG
At least 156 people in Bangladesh were killed during the past week by landslides and floods caused by heavy rainfall.
Scientists unravel the interdecadal variability of the Afro-Asian summer monsoon system
Prof. Yihui Ding from the National Climate Center, China, along with his collaborators, have concluded that the Afro-Asian summer monsoon will continue to enhance and move northwards following the initial stage of the Atlantic Multidecadal Oscillation (AMO) warm phase since the mid-1990s.
NASA observes heavy monsoon rainfall in Sri Lanka
NASA's Global Precipitation Measurement mission or GPM satellite constellation provided rainfall data after the monsoon generated large amounts of precipitation in Sri Lanka that caused landslides over the week of May 22.
NASA sees powerful storms with advancing monsoon in Bay of Bengal
Storms associated with the advancing monsoon in the Northern Indian Ocean's Bay of Bengal were analyzed by NASA with the GPM or Global Precipitation Measurement mission core satellite.
Interdisciplinary studies reveal relationship between solar activity and climate change
A Chinese Program examined the impacts of astronomy and earth motion factors on climate change.
Scientists unravel effect of ENSO and Atlantic multidecadal oscillation on the East Asian winter monsoon
Based on the observations and models' simulation, Drs. HAO Xin and HE Shengping found that the out-of-phase relationship between the variations in ENSO-like mode and the EAWM was significantly intensified when the AMO and ENSO-like SST anomalies are in phase.
Study shows China's severe weather patterns changing drastically since 1960
In one of the most comprehensive studies on trends in local severe weather patterns to date, an international team of researchers found that the frequency of hail storms, thunderstorms and high wind events has decreased by nearly 50 percent on average throughout China since 1960.
Shifting monsoon altered early cultures in China, study says
The annual summer monsoon that drops rain onto East Asia, an area with about a billion people, has shifted dramatically in the distant past, at times moving northward by as much as 400 kilometers and doubling rainfall in that northern reach.
Changing rainfall patterns linked to water security in India
Changes in precipitation, which are linked to the warming of the Indian Ocean, are the main reason for recent changes in groundwater storage in India.

Related Monsoon Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Jumpstarting Creativity
Our greatest breakthroughs and triumphs have one thing in common: creativity. But how do you ignite it? And how do you rekindle it? This hour, TED speakers explore ideas on jumpstarting creativity. Guests include economist Tim Harford, producer Helen Marriage, artificial intelligence researcher Steve Engels, and behavioral scientist Marily Oppezzo.
Now Playing: Science for the People

#524 The Human Network
What does a network of humans look like and how does it work? How does information spread? How do decisions and opinions spread? What gets distorted as it moves through the network and why? This week we dig into the ins and outs of human networks with Matthew Jackson, Professor of Economics at Stanford University and author of the book "The Human Network: How Your Social Position Determines Your Power, Beliefs, and Behaviours".