For nearly 1 billion people living on the subcontinent of India, monsoon rainfall provides water for agriculture, drinking water and hydroelectricity production. The torrential rainfall also can lead to deadly floods and landslides. Scientists have grappled with reliably predicting monsoons in advance, but progress has been slow mainly due to lack of measurements of the phenomena believed to be the building blocks of monsoon weather.
Researchers at the University of Notre Dame are at the forefront of a five-year study to measure oceanic and atmospheric conditions and flow patterns of monsoons across the Indian Ocean, in particular Bay of Bengal, to help improve predictive models.
“We want to understand fundamental processes that regulate monsoons. The active and break cycles of rainfall within a monsoon season, called monsoon intraseasonal oscillations (MISO), are difficult to predict and involve intricate air-sea dynamics,” said Harindra Joseph Fernando, Wayne and Diana Murdy Endowed Professor in the Department of Civil and Environmental Engineering and Earth Sciences at Notre Dame and principal investigator of the study. “Giant atmospheric wave patterns coming from the Indian Ocean impact countries such as India, Sri Lanka, Singapore and Seychelles, and they circumnavigate and affect global weather — much like we see with the polar vortex. The focus of our research is to look at how these planetary-scale waves shape the regional weather and understand the conditions for extreme rainfall events.”
Current models can predict monsoon weather seven to 10 days out. Fernando hopes the study will help improve those predictions to several weeks.
While they bring severe weather to countries in their path, active phases of MISO events also carry a vital resource: water. Access to water is difficult in some countries affected by Asian monsoons, Fernando said. “For India and Sri Lanka, advanced predictions are important for water resource planners. Knowing when the rains are coming in, where they’re coming from and what their tracks are as early as possible would be a significant advantage for water resource management, allowing planners to allocate those resources more efficiently.”
As part of the study, researchers will deploy a number of sophisticated instruments from research ships and an aircraft to measure the ocean and atmospheric properties over two monsoon cycles. They are interested in the temperature, salinity, humidity, flow velocities, turbulence, pressure and wave properties as well as global impacts of MISO events. These measurements will enable researchers to study physical and thermodynamic processes related to MISO.
A number of countries are partnering for the study. Recently Notre Dame signed a five-year memorandum of understanding with the government of Sri Lanka, which will be a main hub of the measurement program.
The funding for the study comes from the U.S. Office of Naval Research. The National Center for Atmospheric Research, National Aquatic Resources Research and Development Agency of Sri Lanka, Maldives Climate Observatory in Hanimaadhoo, Seychelles Meteorological Authority, Army Research Laboratory, Naval Research Laboratory and Charles River Analytics are also participating in the study.
Originally published by news.nd.edu on July 21, 2017.at