Jim Rogers, 75, says the next bear market in stocks will be more catastrophic than any other market downturn that he’s lived through.The veteran investor says that’s because even more debt has accumulated in the global economy since the financial crisis, especially in the U.S. While Rogers isn’t saying that stocks are poised to enter bear territory now -- or making any claim to know when they will -- he says he’s not surprised that U.S. equities resumed their selloff Thursday and he expects the rout to continue.“When we have a bear market again, and we are going to have a bear market again, it will be the worst in our lifetime,” Rogers, the chairman of Rogers Holdings Inc., said in a phone interview. “Debt is everywhere, and it’s much, much higher now.”The plunge in equity markets resumed Thursday, as the S&P 500 Index sank 3.8 percent, taking its rout since a Jan. 26 record past 10 percent and meeting the accepted definition of a correction. The Dow Jones Industrial Average plunged more than 1,000 points, while the losses continued in early Asian trading Friday as the Nikkei 225 Stock Average dropped as much as 3.5 percent.Bear MarketsRogers has seen severe bear markets before. Even this century, the Dow plunged more than 50 percent during the financial crisis, from a peak in October 2007 through a low in March 2009. It sank 38 percent from its high during the IT bubble in 2000 through a low in 2002.“Jim has been talking about severe corrections since I started in business over 30 years ago,” said Alibaba Group Holding Ltd. President Mike Evans, a former Goldman Sachs Group Inc. banker. “So I’m sure he’ll be right at some point.”Rogers predicts the stock market will experience jitters until the Federal Reserve increases borrowing costs. That, he says, will be the point when stocks go up again. He said he’ll buy an agriculture index today, reiterating his view that prices of such commodities have been depressed for some time.“I’m very bad in market timing,” Rogers said. “But maybe there will be continued sloppiness until March when they raise interest rates, and it looks like the market will rally.”