The Desert Dome is the world’s largest indoor desert featuring plant and animal life from three deserts of the world. In the desert dome there are over 360 animals representing 90 species. The desert dome is located under the world’s largest glazed geodesic dome, standing 13 stories tall. The top of the dome is 137 feet above the main level. Although the building is 230 feet in diameter spanning over one acre, there are no support columns except the outer wall. Geodesic is defined as a dome pattern of triangle that provides a strong structure. The 1,760 tinted acrylic panels are three different shades as well as clear, providing maximum shade in the summer and maximum light in the winter.
What is a desert?
Deserts are hot, dry places made up mostly of sand, rock and mountains. In general, deserts are defined as areas where more water evaporates in the air than falls to the ground as rain. Deserts encompass nearly 1/3 of the Earth’s 58 million square miles of land surface.
4 types of deserts
Polar Deserts
Polar deserts have plenty of moisture locked in the ice-cover. They are considered arid because frozen water is not readily available to plants and animals. Antarctica and Artic are polar deserts
Cold-Winter Deserts
Cold–winter deserts are characterized by being hot in the summer and bitterly cold in the winter. They remain arid for two reasons: too far inland to be reached by ocean born moisture or lay in the arid “rain shadow” of mountain ranges that block precipitation. Asia has the largest cold-winter deserts. The Patagonian, Colorado Plateau, Great Basin and Gobi are cold-winter deserts.
Subtropical Deserts
Subtropical deserts are the hottest deserts. High-pressure systems created by regular global wind patterns keep the land dry. These bands of deserts run parallel to the equator straddling the Tropic of Cancer or the Tropic of Capricorn. The Sahara, Arabian Peninsula, Kalahari, Thar, Red Center, Australian Deserts (Great Victoria, Gibson, Great Sandy, Sturt Stony and Simpson), Chihuahuan, Sonoran, and Mojave are subtropical deserts.
Coastal Deserts
Coastal deserts are found in cooler climates influenced by frigid offshore ocean currents. These coastal deserts are rare. They are often blanketed in fog created by temperature inversions. Coastal deserts are considered some of the driest and most uninhabitable places. The Atacama and Namib are coastal deserts.
Deserts represented in the Desert Dome
The Namib is the oldest and most biologically diverse desert on earth. It was created during periods of drought that alternated with wetter periods. Sand dunes can reach up to 1000 feet in height and are almost impassable to man and large animals. The coastal strip of the Namib is one of the driest places on Earth because of the Benguela Sea current. Fog, formed when warm onshore winds meet the cold Benguela current of the South Atlantic, is the chief water source. Further inland the Namib desert has seasonal rains interspersed with long periods of drought to little precipitation.
The Outback, also known as the Red Center, houses the world’s largest monolith, Uluru (Ayers Rock). Rainfall in the Red Center (10-12 inches per year) is very high for a desert. An extremely high evaporation rate cancels out the high rainfall. Most of the rain comes from monsoonal thunderstorms or occasional tropical cyclonic rain depressions.
The Sonoran Desert is the hottest of the four North American deserts, and is considered to be the second most biologically diverse desert in the world. It covers parts of Arizona, California, and the Mexican state of Sonora. Most of the annual rainfall comes from summer thunderstorms. The eastern edge of the Sonoran is the only place Giant Saguarocacti are found.
What is a sand dune?
Wind swept sand patches that form wave like patterns and geometric forms. Shape and size depends on sand availability and wind flow.
How are sand dunes formed?
1—Saltation: occurs when wind currents move sand grains across the desert ground. The process continues until the wind flow is disrupted and the sand grains fall and accumulate. Falling grains of sand hit resting sand grains and propel them into the air.
2—Wind transported sand grains accumulate and pile up around obstacles like boulders, plants or depressions.
3—Sand is transported up the windward face and over the crest of the dune. Sand spills down out of the wind stream.
4—Sand collects on the leeward side of the crest until the sand collapses to form a stable shape.
5—After the sand has collapsed, the cycle starts again with sand moving up the windward face and down the leeward face as the dune moves across the desert.
Common Types of Sand Dunes
Star Dune
A star dune is formed when winds that alternately blow converge from several directions. Arms with sharp ridges that reach up to 262 feet high are formed. This type of dune tends to be immobile.
Transverse Dune
A transverse dune is perpendicular ripples of sand formed in the direction of a moderate wind. It occurs in places with little or no vegetation.
Barchan Dune
The Barchan dune is a crescent shape dune formed by constant wind coming from one directions. Horns (arms) are formed by wind moving faster around the dune than over the windward slope. This type of dune is highly mobile and forms on rocky surfaces.
Parabolic Dune
Parabolic dunes look very similar to the barchan sand dune. The arms are stabilized by vegetation and face the wind. Wind removes sand grains from the center and deposits them on the steeper leeward side.
Sand Dunes in Nebraska?
Nebraska sand hills are very unique. This native grassland covers 19,600 square miles of eolian (wind-deposited) sand dunes. The sand hills are the largest sand dune formation in America. Even though the sand hills are the largest eolian dunes in the Western hemisphere, they are on average smaller than the great “Sand Seas” of North Africa, Arabia, Asia and Australia.
The sand hills were formed by paleowinds (ancient winds) from the northwest. These winds have created six basic types of dunes: 60 feet high barchan, barchanoid-ridge, dome-like, linear, parabolic, and sand sheets. Sand dune formations in Nebraska are very complex.
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