Watermelon snow is snow that is reddish or pink in color, with the slight scent of a fresh watermelon. This type of snow is especially common during the summer in the Sierra Nevada of California. Here, at altitudes of 10,000 to 12,000 feet (3,000–3,600 m), the temperature is cold throughout the year, and so the snow has lingered from winter storms. Compressing the snow by stepping on it or making snowballs leaves it looking red. Walking on watermelon snow often results in getting bright red soles and pinkish pant cuffs, and there are unconfirmed reports that consuming a lot of the snow can cause diarrhea. Scientific classification or biological classification is how biologists group and categorize extinct and living species of organisms (as opposed to folk taxonomy). ... Divisions Land plants (embryophytes) Non-vascular plants (bryophytes) Marchantiophyta - liverworts Anthocerotophyta - hornworts Bryophyta - mosses Vascular plants (tracheophytes) Lycopodiophyta - clubmosses Equisetophyta - horsetails Pteridophyta - true ferns Psilotophyta - whisk ferns Ophioglossophyta - adderstongues Seed plants (spermatophytes) †Pteridospermatophyta - seed ferns Pinophyta - conifers Cycadophyta - cycads Ginkgophyta - ginkgo Gnetophyta - gnetae Magnoliophyta - flowering plants Adiantum pedatum (a fern... Classes Chlorophyceae Ulvophyceae Trebouxiophyceae Prasinophyceae The Chlorophyta sensu stricto or chlorophyte algae, comprises most of what are commonly called green algae and includes most members of the grade of putatively ancestral scaly flagellates in Prasinophyceae plus members of Ulvophyceae, Trebouxiophyceae, and Chlorophyceae. ... Orders see text The Chlorophyceae are one of the classes of green algae, distinguished mainly on the basis of ultrastructural morphology. ... Families Goniaceae Spondylomoraceae Tetrabaenaceae Volvocaceae The Volvocales are an order of flagellate or pseudociliate green algae which form planar or spherical colonies. ... Species see text Chlamydomonas is a genus of green alga. ... In biology, binomial nomenclature is the formal method of naming species. ... Snow is precipitation in the form of crystalline water ice, consisting of a multitude of snowflakes. ... Binomial name Citrullus lanatus (Thunb. ... Sierra Nevada, meaning snowy range in Spanish, is the name of at least two mountain ranges: Sierra Nevada (Spain) in Andalusia, Spain Sierra Nevada (US) in California and Nevada, United States Sierra Nevada (Mexico) in Mexico There are also two single mountains named Sierra Nevada in the Andes which are... Official language(s) English Capital Sacramento Largest city Los Angeles Area  - Total   - Width   - Length   - % water  - Latitude  - Longitude Ranked 3rd 158,302 sq mi  410,000 km² 250 miles  402. ... Diarrhea (American English) or diarrhoea (Commonwealth English) is a condition in which the sufferer has frequent and watery, chunky, or loose bowel movements (from the ancient Greek word διαρροή = leakage; lit. ...

Watermelon snow is caused by the presence in the snow of Chlamydomonas nivalis, a species of green algae containing a bright red carotenoid pigment in addition to chlorophyll. Unlike most species of fresh-water algae, it is cryophilic (cold-loving) and thrives in freezing water. Its specific epithet, nivalis, is from Latin and refers to snow. Divisions Chlorophyta Charophyta Streptophytina (Subdivision) The green algae are the large group of algae from which the embryophytes (higher plants) emerged. ... Carotenoids are organic pigments naturally occurring in plants and some other photosynthetic organisms like algae, some types of fungus and some bacteria. ... In biology, pigment is any material resulting in color in plant or animal cells which is the result of selective absorption. ... Chlorophyll is a green photosynthetic pigment found in plants, algae, and cyanobacteria. ... Psychrophiles are extremophilic organisms that are capable of growth and reproduction in cold temperatures. ... Latin is an ancient Indo-European language originally spoken in the region around Rome called Latium. ...

History

The first accounts of watermelon snow are in the writings of Aristotle. Watermelon snow has puzzled mountain climbers, explorers, and naturalists for thousands of years, some speculating that it was caused by mineral deposits or oxidation products that were leached from rocks. Aristotle (Ancient Greek: Aristotelēs 384 BC – March 7, 322 BC) was an ancient Greek philosopher, who studied with Plato and taught Alexander the Great. ... Natural history is an umbrella term for what are now usually viewed as several distinct scientific disciplines. ...

In May 1818, four ships sailed from England to search for the Northwest Passage and chart the Arctic coastline of North America. Severe weather made them finally turn the ships back, but the expedition made valuable contributions to science. Captain John Ross noticed crimson snow that streaked the white cliffs like streams of blood as they were rounding Cape York off the northwest coast of Greenland. A landing party stopped and brought back samples to England. The Times wrote about this discovery on December 4, 1818: Popular Northwest Passage routes through the Canadian archipelago This article describes the route through the Canadian Arctic. ... Engraving of Ross Sir John Ross (June 24, 1777 – August 30, 1856) was a British rear admiral and Arctic explorer. ... Categories: Australia geography stubs | Peninsulas | Headlands ... The Times is a national newspaper published daily in the United Kingdom. ... December 4 is the 338th day (339th on leap years) of the Gregorian calendar. ... 1818 (MDCCCXVIII) is a common year starting on Thursday of the Gregorian calendar or a common year starting on Saturday of the 12-day slower Julian calendar. ...

Captain Sir John Ross has brought from Baffin's Bay a quantity of red snow, or rather snow-water, which has been submitted to chymical analysis in this country, in order to the discovery of the nature of its colouring matter. Our credulity is put to an extreme test upon this occasion, but we cannot learn that there is any reason to doubt the fact as stated. Sir John Ross did not see any red snow fall; but he saw large tracts overspread with it. The colour of the fields of snow was not uniform; but, on the contrary, there were patches or streaks more or less red, and of various depths of tint. The liquor, or dissolved snow, is of so dark a red as to resemble red port wine. It is stated, that the liquor deposits a sediment; and that the question is not answered, whether that sediment is of an animal or vegetable nature. It is suggested that the colour is derived from the soil on which the snow falls: in this case, no red snow can have been seen on the ice.

A follow-up article three days later erroneously concluded that the coloration was caused by meteoric iron deposits: "...iron being found to be the colourist of all metallic as well as vegetable matter." Image File history File links Quotation marks File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... Map of Baffin Island and surrounding areas, including Baffin Bay. ... Image File history File links Quotation marks File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ...

Watermelon snow was finally attributed to blooms of algae at the end of the nineteenth century.

C. nivalis

C. nivalis is a green alga that owes its red color to a bright red carotenoid pigment, which protects the alga from intense visible and ultraviolet radiation, as well as absorbing heat, which provides the alga with liquid water as the snow melts around it. Algal blooms may extend to a depth of 25 cm (10 inches), with each cell measuring about 30 micrometers in diameter, about four times the diameter of a human red blood cell. It has been calculated that a teaspoon of melted snow contains a million or more cells. The algae sometimes accumulate in sun cups, which are snallow depressions in the snow. The carotenoid pigment absorbs heat and as a result it deepens the sun cups, and accelerates the melting rate of glaciers and snowbanks. Divisions Chlorophyta Charophyta Streptophytina (Subdivision) The green algae are the large group of algae from which the embryophytes (higher plants) emerged. ... Carotenoids are organic pigments naturally occurring in plants and some other photosynthetic organisms like algae, some types of fungus and some bacteria. ... In biology, pigment is any material resulting in color in plant or animal cells which is the result of selective absorption. ... Note: Ultraviolet is also the name of a 1998 UK television miniseries about vampires. ... A red tide resulting from a dinoflagellate bloom discoloring the water on the right An algal bloom is a relatively rapid increase in the population of (usually) phytoplankton algae in an aquatic system. ... A micrometre (American spelling: micrometer), symbol µm, is an SI unit of length. ... Human red blood cells Red blood cells are the most common type of blood cell and are the vertebrate bodys principal means of delivering oxygen from the lungs or gills to body tissues via the blood. ... This article is about the geographical formation. ...

During the winter months, when snow covers them, the algae become dormant. In spring, nutrients, increased levels of light, and meltwater, stimulate germination. Once they germinate, the resting cells release smaller green flagellate cells which travel to the surface of the snow. Once the flagellated cells reach the surface, they may loose their flagellae and form aplanospores, or thick-walled resting cells, or they may function as gametes, fusing in pairs to form zygotes. Parasitic excavate (Giardia lamblia) Green algae (Chlamydomonas) Flagellates are cells with one or more whip-like organelles called flagella. ... A flagellum (plural, flagella) is a whip-like organelle that many unicellular organisms, and some multicellular ones, use to move about. ... Gametes (in Greek: γαμέτες) —also known as sex cells, or spores—are the specialized germ cells that come together during fertilization (conception) in organisms that reproduce sexually. ... This article or section does not cite its references or sources. ...

Many species feed on C. nivalis, including protozoans such as ciliates, rotifers, nematodes, snow worms and springtails. Protozoa (in Greek proto = first and zoa = animal) are single-celled eukaryotes (organisms with nuclei) that show some characteristics usually associated with animals, most notably mobility and heterotrophy. ... Classes & Subclasses Class Karyorelictea Class Heterotrichea (e. ... Classes Seisonoidea Bdelloidea Monogononta The rotifers make up a phylum of microscopic, pseudocoelomate animals. ... Classes Adenophora    Subclass Enoplia    Subclass Chromadoria Secernentea    Subclass Rhabditia    Subclass Spiruria    Subclass Diplogasteria The roundworms (Phylum Nematoda) are one of the most common phyla of animals, with over 20,000 different described species. ... Families Suborder Arthropleona   Superfamily Entomobryoidea    Entomobryidae - slender springtails    Isotomidae - smooth springtails    Oncopoduridae    Paronellidae    Tomoceridae   Superfamily Poduroidea    Brachystomellidae    Hypogastruridae - elongate-bodied springtails    Neanuridae    Odontellidae    Onychiuridae - blind springtails    Poduridae - water springtails Suborder Symphypleona    Dicyrtomidae    Katiannidae    Sminthuridae - globular springtails    Sminthurididae    Bourletiellidae    Arrhopalitidae Springtails (Order Collembola) form the largest of the three orders of...

See also

• Ice algae: algal communities encountered in annual and multi-year sea-ice.

Ice-algae is a general term used to describe all the various types of algal communities encountered in annual and multi-year sea-ice. ...

External links

• Snow algae
• http://waynesword.palomar.edu/plaug98.htm