Contrasting progression phase of Indian summer monsoon during June 2013 and 2014: observational diagnostics

The Indian summer monsoons of 2013 and 2014 had contrasting onset and progression phases. The onset was timely and the progression of 2013 monsoon was the fastest in the last 70 years, whereas 2014 had a delayed onset and a very lethargic progression phase compared to 2013. The initial monsoon month of June exhibited distinct features during 2013 and 2014. This study investigates the scientific rationale behind the observed discrepancy in these years. It is found that large scale conditions played a seminal role in generating and modulating the observed disparity.