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SlideShow: Welcome to the Earth Sciences Department webpage. Welcome to the Earth Sciences Department webpage. Alt text provided via a link below. The slideshow consists of 17 images showing various geologic and atmospheric events and features.

Slide 0 : One of the most impressive geological formations in the eastern United States, the Whaleback Anticline near Shamokin, Pennsylvania, is a superb natural laboratory for geologists and geology students studying the dynamic forces that shaped the planet.

Slide 1 : Most people wouldn't think to vacation in eastern Nevada, but you can find air as cool as any Las Vegas casino in the Caves sections of Cathedral Gorge State Park. The Caves aren't true caves but rather narrow canyons eroded from a Pliocene Epoch lake bed.

Slide 6 : Poas Volcano Crater, shown above, is located in Poas Volcano National Park in Costa Rica: acid lake?

Find out more about the acid lake

Slide 7 : California Cavern: Learn how stalactites form.

Slide 9 : NASA scientists use remote sensing to observe a section of the earth each orbit, and then combine the data from many orbits to recreate the whole earth at once. Sensors in space observe the earth in many different wavelengths of light. Combinations of these images can be used to determine what is growing in each patch of the earth, and even if it is healthy or not. As sensors get better and more sensitive, the size of the smallest patch that can be observed from space gets smaller and smaller - to within a few meters now. Remote sensing data can be used in estimating biomass, soil moisture, changes in elevation, or even animal population densities.

The photo above showing lenticular wave clouds seemingly emanating from the snow-covered summit of Mount St. Helens in southwestern Washington was taken on October 22, 2007. Lenticular clouds are observed when stable air near saturation is forced to flow over mountain ranges, elevated plateaus or high hills. The lifting cools the air to the saturation point thus forming clouds. Lenticulars appear stationary because they're confined to wave crests, which often migrate quite slowly. Photo taken from the U.S. Forest Service VolcanoCam.

Slide 12 : Image of a fabulous solar corona while traveling south from Aberdeen to Glasgow, Scotland, on September 8, 2007. A thick, low-level covering of clouds had just cleared, leaving a thinner veil of mid-level clouds, composed chiefly of water droplets. Minute but very uniform water droplets near the edges of these clouds deflected the Sun's light by the process of diffraction in such a way to produce the vivid metallic colors shown above.

Slide 14 : This is a photo of Logan Pass in Glacier National Park, Montana. Many of the glaciers in this beautiful park have been noticeably receding, but the effects of the glacial ice that nearly covered this corner of northwestern Montana are quite obvious.

Slide 16 : This is a fascinating photo of the "bathtub ring" that represents a water dipstick for the southwestern U.S. and northern Mexico. The boaters are motoring south on the Overton Arm of Lake Mead. The white calcium deposit you see is the 65-year-old water line that is considered the lake's normal water level. At this particular spot, the water level is almost 50 feet (15 m) below the lake's capacity. As of October 12, 2007, Lake Mead storage was 48% of capacity.

Slide 17: Glaciers are abundant in south-central Alaska's Prince William Sound. One showcase glacier is Surprise Glacier, shown above. Note its bluish ice formations. Is glacier ice really blue? No, it just appears to be blue because the longer wavelengths of light (reds and yellows) are more readily absorbed by thick ice than are the shorter wavelengths (blues and greens). Thus, the longer light travels in ice, the bluer it appears. In contrast to thick ice, sunlight does not penetrate very far into snow, therefore it appears white. However, when you poke a hole into deep, fresh snow (more than about 0.3 m or 1 ft in depth), bluish light will emerge