After a big sell-off Wednesday, U.S. stocks climbed back in early trading Thursday. (Michael Nagle/Bloomberg)

U.S. stocks staged a modest recovery Thursday, offering investors a respite from the rocky trading that has wiped out trillions of dollars in market value in three fast weeks.

Slowing economic growth in China and plummeting oil prices have sparked weeks of volatile trading across the globe. But on Thursday, investor confidence appeared to be buoyed by a rebound in oil prices and signs that the European Central Bank might consider stepping up its stimulus plan at its next meeting. That followed another bold move by China’s central bank to sink money into that country’s financial system.

Such moves overseas to stimulate economic growth could weigh on the U.S. Federal Reserve, which meets again next week, market analysts and economists said. In December, the Fed suggested that it could raised rates four times this year, but has cautioned that its forecasts could change as the economic recovery evolves.

It is no longer clear whether the Fed can do so without rattling markets even more.

The Fed is stuck between appearing to buckle to market pressure and risking more market volatility if it doesn’t, said James Bianco, head of Chicago-based investment strategy firm Bianco Research.

“The market doesn’t like it when you take its sugar away, and now it’s throwing a fit,” he said. “The question is how strident is the Fed going to be.”

The questions facing the Federal Reserve are more complex than those facing European bankers, who are grappling with economies that are weaker, analysts said. But it is no longer safe to assume, they said, the Fed can maintain the status quo.

Meanwhile, in Europe, the ECB announced it would leave key interest rates unchanged, but President Mario Draghi added that “conditions have worsened” since the bank last met in December.

“The stimulus trigger looks cocked and ready to pull as soon as the March ECB meeting,” Howard Archer, IHS Global Insight Chief European and British Economist, said in a research note. “The markets clearly took the ECB’s stance as very dovish.”

That helped lift European markets. The FTSE 100 and France’s CAC 40 both climbed more than 1.5 percent Thursday.

But a decision by the People’s Bank of China to pump more than $100 billion in short- and medium-term loans on Thursday was not enough to slow the downward march of Asian stocks. Much of the global market anxiety has been focused on China, the world’s second-largest economy. After many years of robust growth, signs that it has started to slow have sent stocks there down 20 percent. That continued Thursday despite the government’s action, with China’s Shanghai index falling another 3 percent. Japan’s Nikkei was down 2 percent.

In U.S. markets, the Dow Jones industrial average, a barometer of 30 blue-chip stocks, and the Standard & Poor’s 500-stock index, a broader view of the market, both finished with a sigh of relief, closing up less than 1 percent Thursday. The tech-heavy Nasdaq was flat.

That is not enough to restore the heavy losses investors have endured this year. All of the major U.S. indexes are still down nearly 10 percent from their record highs, and market watchers worry that it could take weeks, or perhaps months, before investor anxiety eases and stocks see a sustainable rebound.

“The correction seen in the equity market since the beginning of this year is based on fear, not fundamentals,” Scott Wren, senior global equity strategist, wrote in a Wells Fargo research note.

Worry that a global economic slowdown could destabilize the recovery at home has set stocks on one of their worst yearly starts in history. It may be, some say, that Wall Street is sensing weaknesses in the global economy that are not yet apparent. Others say that, fueled by paranoia, traders are steering the wild stock market ride.

“Recent market moves probably overstate the likelihood of a slump in global growth this year,” Paul Sheard, chief global economist and head of global economics and research at Standard & Poor’s, said in article published Thursday.

Contributing to the volatility have been falling oil prices, which dropped to $26 a barrel Wednesday. On Thursday, prices rebounded to about $29 a barrel after traders found that oil supplies had not grown as much as some feared.

Despite the turnaround, oil prices are still near record lows, weighing down energy companies and banks that have lent them money.

“Certainly oil plays a significant role in it, but there is much more to it,” said Bob Andres, chief investment officer of Andres Capital Management. The fall in oil prices has “exposed the underbelly of an equity market that is way overvalued.”