Carnival Corp. & plc revised its guidance for the second half of 2011, citing the prolonged conflicts in the Middle East and North Africa, as well as the earthquake and nuclear disaster in Japan. Those events resulted in over 300 deployment changes, which will cost the company an additional 15 cents per share for the second half of 2011.

In addition, the company said increased fuel prices will cost the company approximately 5 cents per share in the second half of the year.

Carnival said it “underestimated the full impact of these events on its second-half earnings” in its March guidance, which was announced one week after substantially all the itinerary changes resulting from these events were announced and only days after the Japanese earthquake.

The company said it also experienced softness in bookings for the Southern Europe and U.K. markets, which will result in reduced revenues costing an additional 5 cents per share for the second half of the year.

However, the company expects to offset the effect of these 5 cents per share in other cost areas of the business. “Revenue performance for the North American brands remains strong and the company continues to expect sequential improvement in the second half of the year,” according to a release.

The company will announce second-quarter results and more details of its 2011 full-year guidance in its regularly scheduled earnings release on June 21.