Abstract: In this presentation, I introduce my research mainly on the climate variability and change of the tropical Indo-pacific as well as Indian summer monsoon that I have carried out in the last two decades or so. While the El Niño-Southern Oscillation (ENSO) has been known as the biggest driver Indian summer monsoons, our observational and model studies show that co-occurring positive-IOD events have drastically reduced the effect of strong El Niños. We also show that the IOD events impact the Australian winter climate. The relevance of these tropical drivers for the storm tracks in southern-hemisphere storm tracks will be discussed. I shall present about my major discovery of El Niño Modoki, a tripolar anomalous SST structure in tropical pacific, being increasingly seen since the late 1970s. The distinct impacts and evolution of these will also be discussed. The relevance of the basin-wide background oceanic changes vis a vis westerly wind bursts which decide the type of ENSO will be raised. Climate change adaptation requires that these events be predicted well. I shall brief about my contributions to the seasonal through decadal prediction of the ENSOs and IOD, and applications. In addition to commenting on the challenges the current generation models have in simulating the climate change & variability of the Indian summer monsoon, I shall discuss my leadership efforts in the successful development of the first Indian Earth-System Model. In addition, results from our PMIP3 analysis document the climate change/teleconnections over India through the last millennium. On a different note, our model studies suggest that pre-monsoon aerosols can reduce the current day El Niño impacts on the monsoons. Lastly, the implications of the recent warming of Bay of Bengal vs mega-El Niños for extreme events will be shown. The lingering signature of monsoon in the Arabian sea, and some theoretical aspects related to monsoons will also be introduced. I shall also brief the ongoing collaboration with the KAUST, including the changing teleconnections from the tropical oceanic drivers and LULC importance for extreme events.
Bio: Prof. Karumuri Ashok holds a Ph.D. (1997) in Meteorology from India. After initially working as a scientist at the Indian Institute of Tropical Meteorology (IITM), he moved to JAMSTEC, Japan, in 2000 as a post-doc, and subsequently continued there as a scientist from 2002 through 2007. From August 2007-November 2009, he worked as a senior scientist and Chief of climate operations at the APEC Climate Center, South Korea. Later, he was a senior scientist and the Deputy Program Director at the Climate Change Centre, Indian Institute of Tropical Meteorology, Pune, India. In Aug., 2014, he moved as a full professor to the University of Hyderabad, the one of the premier multi-disciplinary Central university in India and one of the ten institutes of eminence. He is now Professor at the Centre for Earth, Ocean, and Atmospheric Sciences, where he coordinates the MSc (Ocean Atmospheric Sciences) program, in addition to his teaching and research activities. Prof. Ashok was a regular member of Indian teams to the UNFCCC, & to the 2013 IPCC. He was also a contributing author to the IPCC2013 report. Prof. Ashok is an acknowledged researcher on tropical Indo-pacific variability/prediction/impacts. Ashok’s major contribution is the discovery of the El Niño-Modoki events, typified by anomalously warm central tropical-pacific with cooling on both sides, unlike the dipolar structure of the canonical El Niño, and with different impacts. This work triggered global research on distinct ENSO types evolution/impacts. They demonstrated that strong positive IODs reduce the impact of the co-occurring extreme El Niños such as in 1997, and influence Australian climate. Ashok was the lead scientist of the group that developed India’s first earth system model, a flagship project of the Ministry of Earth System Sciences (MoES). The commendable achievement, realized in just 3-4 years under his leadership, facilitated the ongoing global climate-change scenario-simulations being generated at the IITM, first time from India. He also led the development of the operational APCC climate model in South Korea. Interestingly, Prof. Ashok kickstarted the paleo-climate modeling research in India, where he carries out last millennium through mid-Holocene simulations. Prof. Ashok also working on other issues such decadal prediction of climate divers, relevance of recent ocean warming for extreme events, instabilities of active-break cycles, etc. He has a strong collaboration with the KAUST.