Why a sudden boom in commodities?

Mr. Jim Rogers, the greatest proponent of commodities in the world and author of best selling books like ‘Hot Commodities, Investment Biker and Adventure Capitalist’, feels that the bull rally in commodities that began in early 1999, will last till 2014. Rice, sugar, coffee, rubber, cotton and copper are among his favourites. According to him, the 20th century witnessed three long commodity bull runs during 1906-1923, 1933-1953 and 1968-1982, each lasting on an average of around 18 years. Stocks (in the US) have alternated leadership in regular cycles averaging 18 years. We are currently in the midst of another bull run in commodities, which started in early 1999. If history is any indication, the time for peaking of the commodity cycle would be anywhere from 2014-2022. Commodity prices are still far from their all-time high levels. Cotton is still 50% below its all-time high, while soyabean is 60% away from its highs. Sugar prices are 80% below all-time highs, coffee 70% and so is the case with wheat and rubber. Energy prices are near all-time highs, but are still lower when adjusted for inflation.