The volume of annual runoff of almost all of Russia\'s rivers will be substantially affected by global climate change, the Emergencies Ministry\'s Natural Disaster Center said on Wednesday. \"Owing to the expected shifts in temperature and rainfall amounts, the annual runoff of rivers located in the Central and the Volga federal districts will change significantly by 2015 - in comparison with today\'s levels, winter river runoff will increase by 60-90 percent and the summer runoff will rise by 20-50 percent,\" the center\'s head Vladislav Bolov said. In other federal districts there will be a 5-40-percent increase in the annual runoff. \"Along with this, the spring runoff of rivers located in the Central Black Earth economic region and in the southern part of the Siberian Federal District will fall by some 10-20 percent, which will negatively affect spring floods,\" he added. The number of flood disasters Russia will suffer over the next five years is likely to be much higher than the average owing to global climate change, Bolov said earlier this week. The duration of the average flood period may double from 12 to 24 days, or even more. The threat of flood disaster is highest in Russia\'s central European, north European regions, eastern Siberia and the Kamchatka Peninsula.