Bosses cut their earnings guidance to US$4.25-US$4.35, down from their previous estimate of US$4.35-US$4.55.
Earlier this week, Carnival was forced to cancel three trips for its Vista cruise ship next month due to urgent repair work.
It said today that the voyage disruption would dent full-year earnings by up to US$0.10 per share.
Carnival is also expecting to take a US$0.06 per share hit from the US government’s sudden ban on cruises to Cuba.
President Trump’s decision has forced operators to reroute their cruises, which are usually booked and planned months in advance.
“The suddenness of the regulatory change to this high yielding destination has led to a near-term impact on revenue yields,” said Thursday’s announcement.
Chief executive Arnold Donald added that recent booking trends in continental Europe have also been impacted by “ongoing geopolitical and macroeconomic headwinds”.
Second-quarter revenues rise
For the second quarter, revenue rose 11% to US$4.84bn, beating analysts’ average estimate of US$4.53bn. Net income fell to US$451mln, down from US$561mln a year earlier.
Shares dropped 10% shortly after the statement was released to 3,646p, taking the company to the bottom of the FTSE 100 index in London.