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The Indian Ocean Dipole (IOD) is recognised as an important driver of interannual climate variability over different regions of the globe, including the regional monsoon systems. In particular, positive (negative) phases of IOD tend to be associated with above-normal (below-normal) monsoon rainfall over the Indian subcontinent. Realistic simulation of the IOD and Indian summer monsoon connection, however, remains a challenge in many of the state-of-the-art climate models. This study presents an analysis of IOD and its links to the Indian monsoon based on the historical simulations from the IITM Earth System Model (IITM-ESM) and other models that participated in the 6th phase of Coupled Model Intercomparison Project (CMIP6). Our findings indicate that the IITM-ESM provides not only a fairly realistic simulation of the ocean–atmosphere coupled interactions and the Bjerknes feedback processes associated with IOD events but also better captures the summer monsoon precipitation response over the Indian subcontinent during IOD events, as compared to several CMIP6 models. The physical mechanisms contributing to the improved simulation of IOD and its monsoon connection in the IITM-ESM are evaluated in this study. [ABSTRACT FROM AUTHOR]

Background: Genome wide association studies (GWAS), mostly in Europeans have identified several common variants as associated with key lipid traits. Replication of these genetic effects in South Asian populations is important since it would suggest wider relevance for these findings. Given the rising prevalence of metabolic disorders and heart disease in the Indian sub-continent, these studies could be of future clinical relevance. Methods: We studied seven common variants associated with a variety of lipid traits in previous GWASs. The study sample comprised of 3178 sib-pairs recruited as participants for the Indian Migration Study (IMS). Associations with various lipid parameters and quantitative traits were analyzed using the Fulker genetic association model. Results: We replicated five of the 7 main effect associations with p-values ranging from 0.03 to 1.97x10-7. We identified particularly strong association signals at rs662799 in APOA5 (beta=0.18 s.d, p=1.97 x 10-7), rs10503669 in LPL (beta =-0.18 s.d, p=1.0 x 10-4) and rs780094 in GCKR (beta=0.11 s.d, p=0.001) loci in relation to triglycerides. In addition, the GCKR variant was also associated with total cholesterol (beta=0.11 s.d, p=3.9x10-4. We also replicated the association of rs562338 in APOB (p=0.03) and rs4775041 in LIPC (p=0.007) with LDL-cholesterol and HDL-cholesterol respectively. Conclusions: We report associations of five loci with various lipid traits with the effect size consistent with the same reported in Europeans. These results indicate an overlap of genetic effects pertaining to lipid traits across the European and Indian populations. [ABSTRACT FROM AUTHOR]