A change in wind direction led officials to reopen Hawaii Volcanoes National Park on Thursday, two days after it was closed because of elevated sulfur dioxide levels pouring from the erupting Kilauea volcano.

Jim Kauahikaua, scientist-in-charge at the U.S. Geological Survey's Hawaiian Volcano Observatory, said noxious gas continued to rise from Halemaumau Crater, where an explosion Wednesday night blasted rocks at least 230 feet into the air.

But the return of northeasterly trade winds pushed the sulfur dioxide away from visitor areas, park officials said.

The Big Island park had been closed since Tuesday, when 2,000 people were evacuated and taken to hotels in Hilo.

The explosion Wednesday was smaller than the one that occurred March 19, scattering debris over about 75 acres, Kauahikaua said. That blast was the first explosion in Kilauea's main crater since 1924.

Kilauea is one of the world's most active volcanoes. Its current eruption began Jan. 3, 1983.

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