Here's why this markets expert is cautious on earnings

Careful, investors. The upcoming earnings season may bring more pain, Mike Moran, Standard Chartered head of currency economic research, said Tuesday.

"We are still very cautious about what the profits outlook is going to look like. Outside the S&P 500 … we are seeing that growth rates and corporate profitability slow down. This is going to take a little bit more time to play out," he told CNBC's "Squawk on the Street."

"If you look at it on a historical perspective, that has often been a sign of tougher times ahead. We're very cautious about what the outlook actually is," he said.

The U.S. has been in its longest quarterly earnings recession since the financial crisis and the upcoming results are not expected to be positive.

Yellow "Caution" tape is displayed outside of the New York Stock Exchange.
Michael Nagle | Bloomberg | Getty Images
Yellow "Caution" tape is displayed outside of the New York Stock Exchange.

According to S&P Global Market Intelligence, S&P earnings are forecast to have fallen 5.04 percent for the second quarter. The unofficial start to earnings season will take place when Alcoa posts results next Monday.

Ernesto Ramos, head of equities at BMO Global Asset Management, struck a more positive note, however.

"As we move forward, we maybe get another negative quarter but then three strong quarters, mostly driven by oil-company earnings, as oil rebounded from $30 [a barrel] to $50. You're going to see very strong oil earnings coming back into the S&P 500," he said in the same interview. "That's going to be one of the main drivers of earnings recovery in the U.S. market."

U.S. crude prices fell more than 4 percent Tuesday, but have surged more than 25 percent this year.

US crude in 2016