भारतीय उष्णदेशीय मौसम विज्ञान संस्थान
Indian Institute of Tropical Meteorology
An Autonomous Institute of the Ministry of Earth Sciences, Govt. of India
Physics and Dynamics of Tropical Clouds(PDTC)
To study the cloud-aerosol-precipitation interactions using observations and simulations.
To formulate a scientific basis and protocol to enhance rain formation and rain enhancement using the recent cloud seeding technologies and the state-of-the-art instrumentation.
To carry out collocated airborne and integrated ground based observations to understand a) the microphysical changes in the clouds as a result of changes in aerosol particles, b) microphysical and dynamical controls on the rain formation, c) how physical and chemical properties of aerosols may impact radiative forcing and cloud formation, d) how direct and indirect effect of aerosols may be quantified, and e) utilization of observations in formulating process level parameterization for monsoon clouds, f) understand the fog layer microphysics and microscale processes to understand fog formation, evolution and dissipation.
To Study the dynamical, microphysical and electrical characteristics of thunderstorms, and their interactions with each other over the Indian region (which can help in improving their prediction).
To study the interaction of thunderclouds with environmental conditions.
To understand the effect of electrical forces on microphysical characteristics of thunderstorm.
To study boundary layer characteristics by making observation with micrometeorological tower.
To establish India’s first High-Altitude Cloud Physics Laboratory with state-of-the-art instrumentation to measure aerosol, cloud, precipitation and environmental parameters for studying the effect of aerosols on cloud microphysics and in-turn precipitation.
To understand several of the micro physical and dynamical processes involved in aerosol-cloud-precipitation interactions by simultaneously observing them through long-term surface observations.
To investigate a) secondary organic aerosol formation and their effect on cloud microphysics, and b) aerosol-CCN closure using aerosol chemistry and hygroscopicity measurements.
To investigate the spatial distribution of cloud and precipitation systems over the Western Ghats and surrounding regions using polarimetric weather radars and to validate radar reflectivity and rainfall measurements using network of Optical Rain Gauge (ORG) and Disdrometer.
Retrieval of cloud microphysical properties using polarimetric Ka-band radar.
To study the impact of assimilation of Doppler and polarimetric radar products into numerical meso-scale models.
To improve the understanding of cloud, precipitation systems and regional hydrological cycle through space borne observations.
To contribute towards the national space programme in the areas of retrieval of scientific products, validation and through value addition.
The research programs of IITM undertaken during its 11th Five Year Plan (2007-2012) consisted of development of systems and techniques for long range prediction of seasonal mean monsoon and extended range prediction of active/break spells. These involved assessing the component models, viz., models of atmosphere and ocean, coupling strategy, assessment of bias of the coupled model, data assimilation, development of forecast strategy, study of interaction between clouds and environment, etc. Basic research is crucial for improving any prediction capability. Keeping this in mind, stress has been given on strengthening of the Basic Research required for improving models for weather and climate forecast through observational programs under the project ‘Physics and Dynamics of Tropical Clouds’ of the 12th Five Year Plan.
Understanding convection is the goals of the monsoon meteorology. The monsoon rainfall is ultimately linked to the large scale convection. The deep convection over the Indian region is organized in to mesoscale convective systems, frequency of occurrence and morphology of which are in turn modulated by the synoptic scale systems. The large scale wind shear dictates the organization of the cloud system. The large scale circulation produces the cloud systems and microphysics works for the rainfall production from the clouds. Therefore, understanding the rainfall process involves understanding of the large scale environment and cloud processes and their interactions. This would help in developing the convective and microphysical parameterization schemes for the numerical models used for monsoon forecasting.
Better prediction of monsoon requires better understanding of tropical clouds and their interaction with the environment. Here, dynamics and microphysics play a crucial role in cloud formation and in precipitation. Getting a clear understanding of how these dynamical and microphysical processes influence cloud formation is the main goal of this project. The main objective of the project is to formulate an understanding on the direct and indirect effect of aerosols in monsoon environment and to understand the interaction with dynamics and to realize these in improving the convective and microphysical parameterization schemes in numerical models used for monsoon forecasting. Process level studies of tropical clouds are addressed with state-of-the-art ground based and airborne observations and with laboratory facilities.
Aerosols have impact on rainfall processes and play an important role in weather and climate systems. How aerosols interact with clouds needs to be thoroughly studied by taking simultaneous and in situ measurements of aerosols and cloud microphysics. Such measurements can be taken by using airborne platforms (instrumented aircrafts). However, an airborne platform may not give continuous data throughout the monsoon season or the year. To address this need, a ground based cloud physics laboratory at a high altitude station where clouds touch the ground is established for cloud-microphysics measurements together with aerosol and meteorological measurements. The project also addresses the spatio-temporal distributions of thunderstorms over India and their relation to thermodynamic conditions, aerosols, etc. and has established a Lightning Location Network for the study of charge distribution of thunderstorms. The thrust area of this project is in collecting valuable data relating to various atmospheric processes. To enhance the cloud physics studies and to address the national need for such studies, a National Facility for Airborne Research (NFAR) is also being established by procuring a research aircraft.
During weak monsoon conditions, there are demands for cloud seeding to enhance rainfall. Whether cloud seeding can be a feasible and fruitful technique in the country (keeping the local conditions in view) needs to be investigated scientifically. IITM conducted cloud seeding experiments during 2009-11 which are planned to be continued for gaining deeper insights of this research area.
This project has been subdivided in four sub-projects:
1. Cloud and Aerosol Interaction and Precipitation Enhancement Experiment (CAIPEEX)
2. High Altitude Cloud Physics Laboratory (HACPL)
3. Thunderstorm Dynamics
4. Radar and Satellite Meteorology
1. High Altitude Cloud Physics Laboratory (HACPL), Mahabaleshwar
2. Wind Tunnel Laboratory
3. Atmospheric Chemistry
4. Radar Facility
5. Lightning Location Network Laboratory
6. Fluid Dynamics Laboratory
Fig. ICE particle images from CAIPEEX observations show for the first time that Hallet-Mossop ice multiplication is active in the monsoon clouds. This was also simulated in the study.
Observational and simulated cloud microphysical features of rain formation in the mixed phase clouds observed during CAIPEEX
CAIPEEX Aircraft observations noticed higher ice particle concentrations in Hallet–Mossop zone (− 3 to − 8 °C) with existence of smaller and larger cloud droplets, rimed needles columns, and graupel particles. Observations strongly suggested the active presence of Hallet–Mossop (1974) process in this cloud. The higher correlations found between slope and intercept parameters of exponential size distributions indicated efficient secondary ice production as well as to the aggregation growth of ice particles. First time Large Eddy Simulation (LES) in combination with observations unraveled the important role of Hallet-Mossop (HM) process and its link with warm rain and graupel formation and showed that raindrop freezing plays a crucial role in graupel formation in early stage of ice development. The observed mean values of microphysical parameters including liquid water content, ice water content, ice number concentrations, and reflectivity showed good agreement with model simulations. Primary ice nuclei have only a minor role in the total ice mass in these clouds. [Patade S., Shete S., Malap N., Kulkarni G., Prabha T.V., Observational and simulated cloud microphysical features of rain formation in the mixed phase clouds observed during CAIPEEX, Atmospheric Research, 169, March 2016, DOI:10.1016/j.atmosres.2015.09.018, 32-45]
Burman Pramit Kumar Deb, Prabha Thara V., Morrison R., Karipot A., Case study of turbulence in the Nocturnal Boundary Layer during the Indian Summer Monsoon, Boundary Layer Meteorology, online, June 2018, DOI:10.1007/s10546-018-0364-4, 1-24 (Impact Factor 2.573)
Pervez S., Bano S., Watson J.G., Chow J.C., Matawle J.L., Shrivastava Anjali, Tiwari Suresh, Pervez Y.F., Source Profiles for PM10-2.5 Resuspended Dust and Vehicle Exhaust Emissions in Central India, Aerosol and Air Quality Research, 18, June 2018, DOI:10.4209/aaqr.2017.08.0259, 1660-1672 (Impact Factor 2.606)
Roy I., Gagnon A.S., Siingh D., Evaluating ENSO teleconnections using observations and CMIP5 models, Theoretical and Applied Climatology, online, June 2018, DOI:10.1007/s00704-018-2536-z, 1-24 (Impact Factor 2.640)
Srivastava A.K., Bisht D.S., Singh S., Kishore N., Soni V.K., Singh Siddhartha, Tiwari S., Scattering and absorption characteristics of aerosols at an urban megacity over IGB: Implications to radiative forcing, Atmospheric Research, 205, June 2018, DOI:10.1016/j.atmosres.2018.01.018, 107-117 (Impact Factor 3.778)
Chinthalu G.R., Dharmaraj T., Patil M.N., Dhakate A.R., Pawar S.D., Siingh D., Severe cyclonic storm JAL, air-sea interaction perspectives and floods along Andhra Pradesh-Tamilnadu coast, Journal of Indian Geophysical Union, 22, May 2018, 341-348 (Impact Factor 0.000)
Lal D.M., Ghude S.D., Mahakur M., Waghmare R.T., Tiwari S., Srivastava M.K., Meena G.S., Chate D.M., Relationship between aerosol and lightning over Indo-Gangetic plain (IGP), India, Climate Dynamics, 50, May 2018, DOI:10.1007/s00382-017-3851-2, 3865-3884 (Impact Factor 4.146)
Morwal S.B., Narkhedkar S.G., Padmakumari B., Maheskumar R.S., Kulkarni J.R, Characteristics of precipitating monsoon clouds over rain-shadow and drought-hit regions of India using radar, Climate Dynamics, 50, May 2018, DOI:10.1007/s00382-017-3826-3, 3571-3594 (Impact Factor 4.146)
Mukherjee S., Singla V., Pandithurai G., Safai P.D., Meena G.S., Dani K.K., Anil Kumar V., Seasonal variability in chemical composition and source apportionment of sub-micron aerosol over a high altitude site in Western Ghats, India, Atmospheric Environment, 180, May 2018, DOI:10.1016/j.atmosenv.2018.02.048, 79-92 (Impact Factor 3.629)
Thomas L., Malap N., Grabowski W.W., Dani K., Prabha Thara, Convective environment in pre-monsoon and monsoon conditions over the Indian subcontinent: the impact of surface forcing, Atmospheric Chemistry and Physics, 18, May 2018, DOI:10.5194/acp-18-7473-2018, 7433-7488 (Impact Factor 5.318)
Das S.K., Das S.S., Saha K., Murali Krishna U.V., Dani K.K., Investigation of Kelvin-Helmholtz Instability in the boundary layer using Doppler lidar and radiosonde data, Atmospheric Research, 202, April 2018, DOI:10.1016/j.atmosres.2017.11.013, 105-111 (Impact Factor 3.778)
Mudiar D., Pawar S.D., Hazra A., Konwar M., Gopalkrishnan V., Srivastava M.K., Goswami B.N., Quantification of observed electrical effect on the raindrop size distribution in Tropical Clouds, Journal of Geophysical Research, 123, April 2018, DOI:10.1029/2017JD028205, 1-18 (Impact Factor 3.454)
Sin’kevich A.A., Boe B., Mikhailovskii Y.P., Dovgalyuk Y.A., Veremei N.E., Gopalakrishnan V., Murugavel P., Pawar S.D., Investigation of Cu cong seeding effect during rainfall augmentation in India, Russian Meteorology and Hydrology, 43, April 2018, 209-217 (Impact Factor 0.446)
Kalapureddy M.C.R., Sukanya P., Das Subrata K., Deshpande S.M., Pandithurai G., Pazamany A. L., Jha Ambuj K., Chakravarty K., Kalekar P., Devisetty H. K., Annam S., Simple biota removal algorithm for 35 GHz cloud radar measurements, Atmospheric Measurement Techniques, 11, March 2018, DOI:10.5194/amt-11-1417-2018, 1417-1436 (Impact Factor 3.089)
Kumar Sanjay, Siingh D., Singh R.P., Singh A.K., Kamra A.K., Lightning Discharges, Cosmic Rays and Climate, Surveys in Geophysics, online, March 2018, DOI:10.1007/s10712-018-9469-z, 1-39 (Impact Factor 4.413)
Jha Ambuj K., Kalapureddy M.C.R., Devisetty H.K., Deshpande S.M., Pandithurai G., Case study on large-scale dynamical influence on bright band using cloud radar during the Indian summer monsoon, Meteorology and Atmospheric Physics, online, February 2018, DOI:10.1007/s00703-018-0583-8, 1-11 (Impact Factor 1.159)
Matawle J.L., Pervez S., Deb M. K., Shrivastava A.,Tiwari S., PM2.5 pollution from household solid fuel burning practices in Central India: 2. Application of receptor models for source apportionment, Environmental Geochemistry and Health, 40, February 2018, DOI:10.1007/s10653-016-9889-y, 145-161 (Impact Factor 2.616)
Prabhu A., Oh J., Kim I-W, Kripalani R.H., Pandithurai G., SMMR-SSM/I derived Greenland Sea ice variability: links with Indian and Korean Monsoons, Climate Dynamics, 50, February 2018, DOI:10.1007/s00382-017-3659-0, 1023-1043 (Impact Factor 4.146)
Singh S., Tiwari S., Hopke P.K., Zhou C., Turner J.R, Panicker A.S., Singh P.K., Ambient black carbon particulate matter in the coal region of Dhanbad, India, Science of the Total Environment, 615, February 2018, DOI:10.1016/j.scitotenv.2017.09.307, 955-963 (Impact Factor 4.900)
Srivastava P., Dey Sagnik, Srivastava A.K., Singh S., Tiwari S., Most probable mixing state of aerosols in Delhi NCR, northern India, Atmospheric Research, 200, February 2018, DOI:10.1016/j.atmosres.2017.09.018, 88-96 (Impact Factor 3.778)
Dharmaraj T., Patil M.N., Sukumaran C., Murthy B.S., Chinthalu G.R., Chandrasekar E., Rajendran M., Siingh D., Temporal variation of carbon dioxide and water vapor density over a station in west coast of Arabian Sea during sea breeze and land breeze, Journal of Indian Geophysical Union, 22, January 2018, 66-78 (Impact Factor 0.000)
Srivastava A.K., Kumar D., Misra A., Kanawade V.P., Pathak V., Tiwari S., Devara P.C.S., Aerosol characteristics in the upper troposphere and lower stratosphere region during successive and contrasting Indian summer monsoon season, Atmospheric Environment, 173, January 2018, DOI:10.1016/j.atmosenv.2017.11.004, 46-52 (Impact Factor 3.629)
Project: Physics and Dynamics of Tropical Clouds(PDTC)
Project Director: Dr. Thara Prabhakaran, Dr. G.Pandithurai and Dr. S.D.Pawar
Dr. Thara Prabhakaran Scientist-F
Phone No - +91-(0)20-25904371 View Profile
Dr. G.Pandithurai Scientist-F
Phone No - +91-(0)20-25904251 View profile
Dr. S.D. Pawar Scientist-F
Phone No - +91-(0)20-25904284 View Profile
Project: Physics and Dynamics of Tropical Clouds
Project Director: Dr.(Smt.) Thara Prabhakaran, Scientist-E,
Sub-project: Cloud Aerosol Interaction and Precipitation Enhancement (CAIPEEX)
Dr.(Smt.) Thara Prabhakaran Scientist-E & Project Director of Caipeex
Phone No - +91-(0)20-25904371 View profile
Dr. P. D. Safai Scientist-E
Atmospheric Aerosols and Precipitation Chemistry
Phone No - +91-(0)20-25904258 View profile
Dr. Suresh Tiwari Scientist-E
Air Pollution, Precipitation Chemistry
Phone No - +91-(0)20-28743976 View profile
Shri. P. Murugavel Scientist-E
Phone No - +91-(0)20-25904463 View profile
Dr. Atul Kumar Srivastava Scientist-D
Atmospheric aerosols and their direct and indirect impacts
Phone No - +91-(0)20-25904457 View profile
Dr. Y. Jayarao Scientist-D
Phone No - +91-(0)20-25904254 View profile
Dr. Shivsai Dixit Scientist-E
Experimental and Numerical Fluid Dynamics
Phone No - +91-(0)20-25904242 View Profile
Dr. Rahul Reddy Scientist-D
Phone No - +91-(0)20-25904274 View Profile
Dr. Mahen Konwar Scientist-D
Phone No - +91-(0)20-25904489 View Profile
Mr. G. R. Chinthalu Scientist-C
Air-sea Interactions, Satellite Meteorology
Phone No - +91-(0)20-25904237 (O) View Profile
Mr. B. Balaji Scientific-C
Phone No - +91-(0)20-25904353 View profile
CAIPEEX Phase IV experiment was started on 3rd July 2018 and will be conducted for 120 days, depending on availability of suitable clouds. The experiment is being conducted with two aircraft (Beechcraft B200 and C-90) equipped with cloud physics and seeding instruments, Dual polarized radar at Solapur and telemetry links with aircraft, 120 rain gauges over the seeding area, Ground based observations of aerosol, CCN, wind profiles, thermodynamics, etc. Aircraft base is Aurangabad and as of now, completed over 30 hours of research aircraft and 17 hours of seeder aircraft. Key microphysical changes on seeding in the stratus and in convective clouds are gathered. CAIPEEX C-Band Radar images from Solapur are made available on IMD website http://www.imd.gov.in/pages/radar_main.php?adta=slp. High resolution forecast (1km) are made for the flight decisions. The present experiment is on a much larger scale than the previous ones and uses equipments such as dual polarized radar, rain gauge network and is one of the few of its kind focusing exclusively on the science of cloud seeding.
High Altitude Cloud Physics Laboratory (HACPL):
IITM singed an MoU with Madhya Pradesh Council of Science and Technology (MPCOST) for establishment of atmospheric research test bed facility in Central India on 11 January 2018 at MoES, New Delhi. A Scientific Steering Committee meeting was conducted regarding the establishment of Atmospheric research test bed on 31 July 2018 at IITM. Augmented Particles into Liquid Samples with Ion Chromotograph (PILS-IC) at HACPL for studying aerosol chemical composition and its influence on CCN activation. Ice Nuclei measurements at HACPL are being analyzed to quantify the fraction of aerosols that act as Ice Nuclei.
Radar and Satellite Meteorology:
Both the X-band and Ka-band radars along with HACPL in-situ measurements of CCN, aerosol, cloud microphysics and precipitation were being used to conduct the Monsoon-2018 campaign from May 2018.
Mumbai Weather Live (MWL) Mobile App is developed by collating measurements from India Meteorological Department (IMD), SAFAR-Mumbai (IITM) and MCGM measurements to provide live location specific information on rainfall. Currently, it covers about 100 sites spread across Mumbai city, suburban areas, Navi Mumbai and surrounding areas. A Distrometer has been installed at IMD, Santa Cruz, Mumbai for analyzing microphysical characteristics during heavy rainfall events in Mumbai. The data will also be helpful for calibrating the Dopler Weather Radar of Mumbai.
For the first time, IITM has established with observational evidence that electrical forces can play major role in rain formation processes in tropical clouds. The study used the data of Drop size distribution (DSD) measured by a micro rain radar in six strongly electrified and six weakly electrified stratiform rain events together with the DSD of raindrops at the surface measured by a disdrometer for the same cases. The presence/absence of lightning is used to distinguish between strongly and weakly electrified events. Results indicate that the electric field and surface charge of raindrops can affect the collision-coalescence process and breakup characteristics of raindrops.
The existing Lightning Location Network over Maharashtra is being expanded to other parts of the country with the induction of 28 additional sensors. New sensors are being installed over Kerala, Northeast India, Odhissa, West Bengal and Himalayan region.
A mobile App is developed and is being tested for disseminating information on exact location of lightning strike and its movement to the public and warming them about the possible lightning strikes atleast 30 minutes in advance.
A SMS alert system is developed in association with Reliance Foundation for sending audio and text message warning to people in the area of impending lightning strikes.