Mount St. Helens sports one of the few glaciers in the world that appears to be growing, an especially notable development during a time of increasing concern over global climate changes.

Positioned along the shaded interior of the crater created by the eruption of May 18, 1980, a glacier grew to a thickness of 600 feet. The glacier eventually wrapped like a collar around the 876-foot-tall lava dome that sputtered up from the crater floor in a series of eruptions between 1980 and 1986. Then came the eruption of 2004.

A new plug of solid rock rumbled steadily up through the glacier, ultimately growing big enough to fill Portland?EUR??,,????'???s Rose Garden arena 150 times over. The swelling dome uplifted, deformed and shoved the glacier out of its way. Curiously, it didn?EUR??,,????'???t melt much of it. Scientists estimate that the glacier lost only 10 percent of its volume of intermingled ice, rock and dust.

We?EUR??,,????'???ve all been surprised at how little melt has actually happened, says Carolyn Driedger, a hydrologist with the U.S. Geological Survey in Vancouver. ?EUR??,,????'??Intuitively, you would certainly expect more snow and ice melt.?EUR??,,????'??

Meanwhile, two severed ?EUR??,,????'??arms?EUR??,,????'?? of the glacier have been shoved around the old lava dome and northward down the crater slope ?EUR??,,????'??+ covering an area roughly the size of downtown Portland. The ends of the two arms, each looming 60 to 130 feet in height, lately have moved closer together in a kind of geological embrace.

Now that the ongoing volcanic eruption has paused, scientists wonder about the glacier?EUR??,,????'???s long-term prognosis.

?EUR??,,????'??I imagine, over time, you?EUR??,,????'???ll see the two arms kind of merge and see a flatish lobe out there wherever you have rock on the surface,?EUR??,,????'?? said Joe Walder, a USGS glaciologist.