Climate
The Tularosa Basin, a high desert area, averaging 4,000 feet 1200+ meters in elevation, is subject to harsh, and sometimes rapidly changing climatic conditions. Summers are hot, with high temperatures averaging 95°F. 35°C. in July and August. Winters are relatively mild, but night time temperatures often go below freezing 0°C. and cold spells can send the mercury below zero 0°F / -17°C. The lowest recorded temperature is -25°F -32°C. Snowfall is infrequent, but heavy snows have occurred on occasion. Precipitation averages about 8 inches 20cm. per year, with most falling during summer thunderstorms, often accompanied by lightning and hail.
Wind is the dominant climatic factor, especially from February through May. The prevailing southwesterly winds blow unimpeded across the desert and at times reach gale force. Wind storms can last for days in the spring. This is the time of the greatest dune movement, when living conditions for dune animal and plant communities become extremely harsh.
Flora and fauna
Most of the animals of White Sands have developed nocturnal habits to escape predators and the desert heat. In addition, due to the white sands some animals have evolved lighter coloration; there are forms of white reptiles, mammals, and invertebrates that blend with their white background you probably won't see them unless they move. However, of the 44 species of mammals, 26 species of reptiles, 6 species of amphibians and nearly 100 families of insects recorded on the monument, the vast majority have normal coloration. Lizards can be readily observed in the interdunal areas where vegetation can be found for shade and protection. The park's mammals are primarily noctournal, so are not as easily observed. The light-colored amphibian, the spadefoot toad, only ventures from underground following thunderstorms when water is available for breeding and egg-laying in the pools of rainwater, where tadpoles quickly develop into adults and burrow into the moist sand, where they await the next season's storms.
Landscape
The obvious natural feature of this monument is the pure gypsum dunes, but perhaps less obvious are the sources of the dunes, Lake Lucero and Alkali Flat. These two areas are the result of the gradual drying of an extensive Pleistocene lake that was rich in the mineral gypsum, with the dunes being the result of weathering and wind transport of these exposed surfaces.
The translucent golden-yellow crystals of selenite gypsum grow in saturated mud beneath the lake's remains. When exposed on the surface, these crystals are subject to weathering and erosion and may eventually become gypsum powder and sand grains, which can be carried by winds as dust or sand storms to become the white sands of White Sands National Monument.
History
White Sands became a national monument on January 18, 1933 by order of President Herbert Hoover. Efforts to preserve the area's brilliant gypsum dunes had begun in the late 1800's, but it was the enthusiasm of local booster Tom Charles that finally led to the park's creation. In his words "gypsum may be divided into two classes - Commercial and Inspirational. The former everybody has, but as for recreational gypsum, we have it all. No place else in the world do you find these alabaster dunes with the beauty and splendor of the Great White Sands".
The park's creation coincided with the Great Depression, which was in some ways fortuitous due to the Roosevelt administration's focus on public works. WPA funds were used to improve many park areas and White Sands benefited by achieving a full measure of development within just a few years of opening. In its first year the park attracted 12,000 people, and today as many as 600,000 people visit the park annually.