New Delhi, June 7 (PTI) Climate change has hampered the ability of the forecasting agencies to accurately predict severe events and weather bureaus across the world are focusing on augmenting the observational network density and the weather prediction modelling to improve predictability, India Meteorological Department (IMD) Director General Mrutyunjay Mohapatra has said.He also said that though the monsoon rainfall has not shown any significant trend in the country, the number of heavy rainfall events has increased and that of light rainfall events has decreased due to climate change.