ENSO Transition Mode (ETM)

The ENSO transition mode (ETM) is a climate mode of the southern hemisphere Indo-Pacific Ocean domain, especially prominent during boreal spring. The positive phase of this mode is characterized by a zonal dipole of surface pressure over the southern Pacific Ocean with an increase in pressure toward the east. It creates a surface wind pattern that helps increase the eastern equatorial Pacific sea surface temperature (SST0 from boreal winter to summer. In other words, a positive phase of ETM helps develop a positive phase of ENSO (El Nino) or helps weaken a negative phase of ENSO (La Nina). ETM forcing is most effective in modulating such transition at the multidecadal time scales (~50 years). See here for details.
Reference: Srivastava et al. (2024) .

• Singhai, P., Arindam Chakraborty, K Jana, K Rajendran, S Surendran, K Pegion, 2024:The curious case of a strong relationship between ENSO and Indian summer monsoon in CFSv2 model, Dynamics of Atmospheres and Oceans, DOI: DOI: https://doi.org/10.1016/j.dynatmoce.2024.101504
• Shikhar Srivastava, Arindam Chakraborty, and Raghu Murtugudde, 2024: Decadal preference of seasonal ENSO transition through a southern hemisphere climate mode, Environmental Research Letters, 19 (6) DOI: DOI: 10.1088/1748-9326/ad4bf7

2023

• Samuel, J.B., and A. Chakraborty, 2023: Integration of a Groundwater Model to the Noah Land Surface Model for Aquifer-Soil Interaction, Journal of Advances in Modeling Earth Systems, DOI: https://doi.org/10.1029/2022MS003153
• Singhai, P, A. Chakraborty, K Rajendran, and S Surendran, 2023: Why is the Indian summer monsoon in CFSv2 hypersensitive to moisture exchange with the Pacific Ocean?, Climate Dynamics, DOI: https://doi.org/10.1007/s00382-023-06815-6
• Samuel, J.B., A. Chakraborty, and A. Paleri, 2023: Deciphering the relationship between vegetation and Indian summer monsoon rainfall, Environmental Research letters, 18, 044023, DOI: https://doi.org/10.1088/1748-9326/acc263
• Nikumbh, A.C., ABS. Thakur, A. Chakraborty, G.S. Bhat, and J. Sukhatme, 2023: The role of North Atlantic blocking high during large-scale heavy rainfall events over central India, Journal of the Atmospheric Sciences, DOI: https://doi.org/10.1175/JAS-D-22-0185.1
• Chakraborty, A., JB Samuel, and A. Paleri, 2023: Role of land-surface vegetation in the march of Indian monsoon onset isochrones in a coupled models, Quarterly Journal of the Royal Meteorological Society, 149, 115-132, DOI: https://doi.org/10.1002/qj.4398

2022

• Vishnu, S., Arindam Chakraborty, and J. Srinivasan, 2022: Why the Droughts of the Indian Summer Monsoon are more Severe than the Floods, Climate Dynamics, DOI: https://doi.org/10.1007/s00382-021-06111-1
• Jalihal, Chetankumar, J. Srinivasan, Arindam Chakraborty, 2022: Response of the low-level jet to precession and its implications for proxies of the Indian monsoon, Geophysical Research Letters, DOI: https://doi.org/10.1029/2021GL094760

2021

• Chakraborty, Arindam and Priyanshi Singhai, 2021: Asymmetric response of the Indian summer monsoon to positive and negative phases of major tropical climate patterns, Scientific Reports, DOI: https://doi.org/10.1038/s41598-021-01758-6
• Nikumbh, A. C., Arindam Chakraborty, G. S. Bhat, and D.M.W. Frierson, 2021: Multiscale interactions between monsoon intra-seasonal oscillations and low pressure systems that produce heavy rainfall events of different spatial extents, Journal of Climate, DOI: https://doi.org/10.1175/JCLI-D-21-0231.1
• Rohit Chakraborty, Arindam Chakraborty, Ghouse Basha, Venkat Ratnam Madineni, 2021: Lightning occurrences and intensity over the Indian region: long-term trends and future projections, Atmospheric Chemistry and Physics, 07/2021; 21: 11161-11177.
• Rajendran, K., Surendran, S., Varghese, S.J. and Arindam Chakraborty, 2021: Do seasonal forecasts of Indian summer monsoon rainfall show better skill with February initial conditions?, Current Science, 120 (12) 1863-1874

2020

• Arushi, PV, Arindam Chakraborty, and RS Nanjundiah 2020: Recent Weakening in MJO Related Convective Activity over the Equatorial Indian Ocean and Maritime Continent, Theoretical and Applied Climatology, DOI: 10.1007/s00704-020-03423-w.
• Nikumbh, A. C., Arindam Chakraborty, G. S. Bhat, and D.M.W. Frierson, 2020: Large-scale extreme rainfall-producing synoptic systems of the Indian summer monsoon., Geophysical Research Letters, doi:https://doi.org/10.1029/2020GL088403
• Jalihal, C., J. Srinivasan, and Arindam Chakraborty, 2020: Different precipitation response over land and ocean to orbital and greenhouse gas forcing, Scientific Reports (Nature), doi:https://doi.org/10.1038/s41598-020-68346-y
• Agrawal, S., and Arindam Chakraborty, 2020: Evaluation of ESACCI satellite soil moisture product using in-situ observations over India, Journal of Earth System Science, doi: https://doi.org/10.1007/s12040-020-01384-2
• Srivastava, G., Arindam Chakraborty, Ravi S. Nanjundiah, 2020: Multidecadal variations in ENSO-Indian summer monsoon relationship at sub-seasonal timescales, Theoretical and Applied Climatology, doi:10.1007/s00704-020-03122-6
• Singhai, P., Shibin Balakrishnan, E. N. Rajagopal, Arindam Chakraborty, 2020: Phase inconsistency as a major source of error in NGFS forecast, Climate Dynamics, doi:10.1007/s00382-020-05148-y
• Karmakar, N, Arindam Chakraborty, Ravi S. Nanjundiah, 2020: Influence of global sea surface temperature on ultra‐low frequency variability in the Indian summer monsoon rainfall, Quarterly Journal of the Royal Meteorological Society, doi:10.1002/qj.3715

2019

• Chakraborty, Arindam, 2019: Zonally symmetric vs asymmetric North Pacific Ocean sea surface temperature influence on Indian summer monsoon through modulation of upper tropospheric circulation, Mausam, 70, 4 (October 2019), 753-766 [PDF]
• Jalihal, C., J. Srinivasan, and Arindam Chakraborty, 2019: Modulation of Indian monsoon by water vapor and cloud feedback over the past 22,000 years, Nature Communinications, 10, 5701 (2019) doi:10.1038/s41467-019-13754-6
• Jana, K, D Sengupta, S Kundu, Arindam Chakraborty and P Shaw, 2019: The Statistical Face of a Region Under Monsoon Rainfall in Eastern India, Journal of the American Statistical Association, DOI: 10.1080/01621459.2019.1681275
• Nikumbh, A.C., Arindam Chakraborty, and G.S. Bhat, 2019: Recent spatial aggregation tendency of rainfall extremes over India, Scientific Reports, 9, 10321, doi:10.1038/s41598-019-46719-2
• Jalihal, C., JHC Bosmans, J Srinivasan, and Arindam Chakraborty, 2019: The response of tropical precipitation to Earth's precession: the role of energy fluxes and vertical stability, Climate of the Past, 15, 449–462, https://doi.org/10.5194/cp-15-449-2019
• Agrawal, S., Arindam Chakraborty, N. Karmakar, Simon Moulds, Ana Mijic and Wouter Buytaert, 2019: Effects of winter and summer-time irrigation over Gangetic Plain on the mean and intra-seasonal variability of Indian summer monsoon, Climate Dynamics, 53: 3147. https://doi.org/10.1007/s00382-019-04691-7
• Das, S., D. Sengupta, and Arindam Chakraborty, 2019: The Madden‐Julian oscillation in an aquaplanet‐like general circulation model with and without continents. Journal of Advances in Modeling Earth Systems, 11, 1459–1476. https://doi.org/10.1029/2018MS001455
• Srivastava, G, Arindam Chakraborty, and R.S. Nanjundiah, 2019: Multidecadal see-saw of the impact of ENSO on Indian and West African summer monsoon rainfall. Climate Dynamics 52.11, 6633-6649. [Bibtex Citation]

2018

• Shawki, D, A. Voulgarakis, Arindam Chakraborty, M. Kasoar, and J. Srinivasan, 2018: The South Asian Monsoon Response to Remote Aerosols: Global and Regional Mechanisms. Journal of Geophysical Research (Atmospheres), doi:10.1029/2018jd028623.
• Chakraborty, Arindam, 2018: Preceding winter La Niña reduces Indian summer monsoon rainfall. Environmental Research Letters, 13, 054030, doi:10.1088/1748-9326/aabdd5.
• Jain, D., Arindam Chakraborty, and R.S. Nanjundaiah, 2018: A Mechanism for the Southward Propagation of Mesoscale Convective Systems Over the Bay of Bengal. Journal of Geophysical Research (Atmospheres), 123, 3893-3913, doi:10.1002/2017JD027470.
• Ghosh, R., Arindam Chakraborty, and R.S. Nanjundiah, 2018: Relative role of pre-monsoon conditions and intraseasonal oscillations in determining early-vs-late Indian monsoon intensity in a GCM. Theoretical and Applied Climatology, 131, 319–333, doi:10.1007/s00704-016-1970-z.

2017

• Karmakar, N., Arindam Chakraborty, and R.S. Nanjundiah, 2017: Increased sporadic extremes decrease the intraseasonal variability in the Indian summer monsoon rainfall. Scientific Reports, 7, 7824, doi:10.1038/s41598-017-07529-6.
• Chakraborty, Arindam, and S. Agrawal, 2017:Role of west Asian surface pressure in summer monsoon onset over central India. Environmental Research Letters, 12, 074002.
• Arushi PV, Arindam Chakraborty, and R.S. Nanjundiah, 2017: Orographic control of the Bay of Bengal cold pool rainfall. Journal of Earth System Science, 126, 111, doi:10.1007/s12040-017-0892-1.
• Bhattacharya, A, Arindam Chakraborty, and V. Venugopal, 2017: Role of aerosols in modulating cloud properties during active-break cycle of Indian summer monsoon. Climate Dynamics, 49(5-6), 2131-2145.
• Karmakar, N., Arindam Chakraborty, and R.S. Nanjundiah, 2017: Space-Time Evolution of the Low- and High-Frequency Intraseasonal Modes of the Indian Summer Monsoon. Monthly Weather Review, doi:10.1175/MWR-D-16-0075.1. [PDF]

2016

• Agrawal, S., and Arindam Chakraborty, 2016: Role of surface hydrology in determining the seasonal cycle of Indian summer monsoon in a general circulation model. Hydrology Earth Syst Sci Discuss, 1-33, doi:10.5194/hess-2016-591 [PDF]
• Chakraborty, Arindam, 2016: A synoptic scale perspective of heavy rainfall over Chennai in November 2015, Current Science, 111 (1), 201-207. [PDF]
• Das S, D Sengupta, Arindam Chakraborty, J Sukhatme, R Murtugudde, 2016: Low-frequency intraseasonal variability in a zonally symmetric aquaplanet model. Meteorology and Atmospheric Physics. 2016 Dec 1;128(6):697-713.

2015

• Karmakar, N., Arindam Chakraborty, Ravi S Nanjundiah, 2015: Decreasing intensity of monsoon low frequency intraseasonal variability over India, Environmental Research Letters, 10, doi:10.1088/1748-9326/10/5/054018.

2014

• Chakraborty, Arindam., Ravi S. Nanjundiah, and J. Srinivasan, 2014: Local and remote impacts of direct aerosol forcing on Asian monsoon, International Journal of Climatology, DOI: 10.1002/joc.3826. [PDF]
• Bhattacharya, A., Arindam Chakraborty and V Venugopal, 2014: Variability of cloud liquid water and ice over South Asia from TMI estimates, Climate Dynamics, DOI 10.1007/s00382-013-1978-3. [PDF]
• Chakraborty, Arindam, and Ravi S Nanjundiah, 2014: Role of Orography in Modulating Space-time Scales of Convection over South Asia, Theoretical and Applied Climatology, DOI 10.1007/s00704-013-0963-4. [PDF]

2013

• Jain, D. K., Arindam Chakraborty, and R S Nanjundiah, 2013: Role of the cloud adjustment time scale in simulation of the interannual variability of Indian summer monsoon, Meteorology and Atmospheric Physics, 122:159-173. [PDF]
• Ramasesha, S and Arindam Chakraborty, 2013: Power generation using wind energy in northwest Karnataka, India, Current Science, 104, 757-761. [PDF]

2012

• Chakraborty, A and R S Nanjundiah, 2012: Space-time Scales of Northward Propagation of Convection During Boreal Summer, Monthly Weather Review, 140, 3857-3866. [PDF]
• Krishnamurti, T. N., Anu Simon, Aype Thomas, Akhilesh Mishra, Dev Sikka, Dev Niyogi, Arindam Chakraborty, Li Li, 2012: Modeling of Forecast Sensitivity on the March of Monsoon Isochrones from Kerala to New Delhi, The First 25 Days, J. Atmospheric Science, 69, 2465-2487. [PDF]
• Meehl, Gerald A., Julie M. Arblaster, Julie M. Caron, H. Annamalai, Markus Jochum, Arindam Chakraborty, Raghu Murtugudde, 2012: Monsoon Regimes and Processes in CCSM4. Part I: The Asian–Australian Monsoon. J. Climate, 25, 2583–2608. [PDF]
• Jain, D. K., Arindam Chakraborty, and R S Nanjundiah, 2012: On the role of cloud adjustment time scale in simulating precipitation with Relaxed Arakawa–Schubert convection scheme, Meteorology and Atmospheric Physics, 115, 1-13. [PDF]

2010

• Chakraborty, A., 2010: The Skill of ECMWF Medium Range Forecasts During the Year of Tropical Convection 2008, Monthly Weather Review, 138, 3787-3805. [PDF]
• Krishnamurti, T. N., Arindam Chakraborty, and A. K. Mishra, 2010: Improving multimodel forecasts of the vertical distribution of heating using the TRMM profiles, J. Climate, 23, 1089-1094. [PDF]

2009

• Krishnamurti, T. N., R. Krishnamurti, A. D. Sagadevan, Arindam Chakraborty, W. K. Dewar, C. A. Clayson, and J. F. Tull, 2009: Space-time stuctures of earthquakes, Meteorology and Atmospheric Physics, 105, 69-83. [PDF]
• Chakraborty, A., and T. N. Krishnamurti, 2009: Improving global model precipitation forecasts over India from downscaling and FSU superensemble. Part II: Seasonal climate, Monthly Weather Review, 137, 2736-2757. [PDF]
• Krishnamurti, T. N., A. K. Mishra, Arindam Chakraborty, and M. Rajeevan, 2009: Improving Global Model Precipitation Forecasts over India Using Downscaling and the FSU Superensemble. Part I: 1–5-Day Forecasts, Monthly Weather Review, 137, 2713-2735. [PDF]
• Krishnamurti, T. N., A. D. Sagadevan, Arindam Chakraborty, A. K. Mishra, A. Simon, and S-H Chen, 2009: Improving Multimodel Forecast of Monsoon Weather over China using FSU Superensemble, Advances in Atmospheric Sciencese, 26, 813-839. [PDF]
• Krishnamurti, T. N., Arindam Chakraborty, Andrew Martin, William K Lau, Kyu-Myong Kim, Yogesh Sud and Gregory Walker, 2009: Impact of Arabian Sea Pollution on the Bay of Bengal Winter Monsoon Rains, Journal of Geophysical Research: Atmosphere, 114, D06213, doi:10.1029/2008JD010679. [PDF]
• Chakraborty, A., Ravi S. Nanjundiah, and J. Srinivasan, 2009: Impact of African Orography and Indian Summer Monsoon on the Low-Level Somali Jet, International Journal of Climatology, 29, 983-992. [PDF]

2008

• Chakraborty, A., and T. N. Krishnamurti, 2008: Improved forecasts of diurnal cycle in tropics using multiple global models. Part II: Asian Summer Monsoon, Journal of Climate, 21, 4045–4067. [PDF]
• Krishnamurti, T. N., C. Gnanaseelan, A. K. Mishra and Arindam Chakraborty, 2008: Improved Forecasts of Diurnal Cycle in Tropics Using Multiple Global Models. Part I: Precipitation, Journal of Climate, 21, 4029–4043. [PDF] [Bibtex Citation]

2007

• Krishnamurti, T. N., Arindam Chakraborty, R. Krishnamurti, W. K. Dewar, and C. Clayson, 2007: Passage of intraseasonal waves in the subsurface oceans, Geophysical Research Letters, 34, doi: 10.1029/2007GL030496. [PDF] [Bibtex Citation]
• Chakraborty, A., T. N. Krishnamurti and C. Gnanaseelan, 2007: Prediction of the Diurnal Cycle using a Multimodel Superensemble. Part II: Clouds, Monthly Weather Review, 135, 4097-4116. [PDF] [Bibtex Citation]
• Krishnamurti, T. N., C. Gnanaseelan, and Arindam Chakraborty, 2007: Prediction of the Diurnal Cycle using a Multimodel Superensemble. Part I: Precipitation, Monthly Weather Review, 135, 3613-3632. [PDF] [Bibtex Citation]
• Ross, R. S., Arindam Chakraborty, Anthony Chen, L. Stefanova, S. Sirdas and T. N. Krishnamurti, 2007: Improved Seasonal Climate Forecasts for the Caribbean Region using a Multi-Model Superensemble, Meteorology and Atmospheric Physics, doi: 10.1007/s00703-006-0234-3. [PDF] [Bibtex Citation]
• Sirdas, S., Robert S. Ross, T. N. Krishnamurti and Arindam Chakraborty, 2007: Evaluation of the FSU Synthetic Superensemble Performance for Seasonal Forecasts over the Euro-Mediterranean Region, Tellus-A, 59, 50-70. [PDF] [Bibtex Citation]

2006

• Chakraborty, A., R. S. Nanjundiah, and J. Srinivasan, 2006: Theoretical aspects of the onset of Indian summer monsoon from perturbed orography simulations in a GCM, Annales Geophysicae, 24, 2075-2089. [PDF] [Bibtex Citation]
• Krishnamurti, T. N., Arindam Chakraborty, R. Krishnamurti, W. K. Dewar, C. A. Clayson, 2006: Seasonal Prediction of Sea Surface Temperature Anomalies Using a Suite of 13 Coupled Atmosphere-Ocean Models, Journal of Climate, 19, 6069-6088 [PDF] [Bibtex Citation]
• Chakraborty, A., T. N. Krishnamurti, 2006: Improved Seasonal Climate Forecasts of the South Asian Summer Monsoon Using a Suite of 13 Coupled Ocean-Atmosphere Models, Monthly Weather Review, 134, 1697-1721. [PDF] [Bibtex Citation]

Before 2006

• Chakraborty, A., S. K. Satheesh, R. S. Nanjundiah, and J. Srinivasan, 2004: Impact of absorbing aerosols on the simulation of climate in the Indian region in an atmospheric general circulation model.Annales Geophysicae., 22, 1421-1434. [PDF] [Bibtex Citation]
• Chakraborty, A., and J. Srinivasan, 2003: Comparison of radiative fluxes at the top of the atmosphere from INSAT and ERBE, Mausam, 54, 299-314. [PDF] [Bibtex Citation]
• Chakraborty, A., R. S. Nanjundiah, and J. Srinivasan, 2002: Role of Asian and African orography in Indian summer monsoon., Geophysical Research Letters, 29, 10.1029/2002GL015522. [PDF] [Bibtex Citation]
• Bhat, G. S., Arindam Chakraborty, R. S. Nanjundiah and J. Srinivasan, 2002: Vertical thermal structure of the atmosphere during active and weak phases of convection over the north Bay of Bengal: Observation and model results, Current Science, 83, 296-302. [PDF] [Bibtex Citation]

• Arindam Chakraborty and J Srinivasan, 2019: Indian Summer Monsoon, Research News, Current Science, 117
• Deepeshkumar Jain, Arindam Chakraborty and Ravi S. Nanjundiah, 2019: Convective Available Potential Energy and Precipitation in a Cloud-Resolving Model Simulation of Indian Summer Monsoon, in Current Trends in the Representation of Physical Processes in Weather and Climate Models, Eds: David Randall, J Srinivasan, RS Nanjundiah, P Mukhopadhyay, Springer Atmospheric Sciences, 113-138.
• Arindam Chakraborty, 2016: The Inscrutable monsoon? Current Science, 111 (8), 1305-1306.

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