Grand Pristmatic Spring

Yesterday i went out with Pat & Bill


first we went ot West Yellowstone to buy something
there we stepped on our trip!!
we drove along the road from Madison to Old Faithful
they drove Firehole Canyon Drive for showing me the beautiful firehole river
and there was a swimming area along the river
where were so many people there!!!


and them we drove the Firehole Lake Drive
there are many hot spring along the road
and in the end of the road was the Firehold Lake
it's a hot spring i guess, it keeped steaming!!!
and the wind was so big, all the steam came to us, made us feel so warm!!!
the lake was so beautiful and big!!!


and the next destination is the place which i want to see most in Yellowstone
Grand Pristmatic Spring
















it located at Midway Geyser Basin
there are 3 geysers here, but this one is one i like most
why i like it most??
because i just saw the picture in Taiwan there years ago

there was a photographer traveling the world and took pictures from the high attitude
he ones had an exhibition along the love river in Kaohsiung
and there was the time i met this spring
it was just like a rainbow, the color is so charming... attractive to me
it made a deep impression to me
and yesterday.... i finally saw it live....

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from: Wiki

It's the largest hot spring in United States, and the 3rd largest in the world

[color]
The vivid colors in the spring are the result of pigmented bacteria in the microbial mats that grow around the edges of the mineral-rich water. The bacteria produce colors ranging from green to red; the amount of color in the microbial mats depends on the ratio of chlorophyll to carotenoids. In the summer, the mats tend to be orange and red, whereas in the winter the mats are usually dark green.[5] The center of the pool is sterile due to extreme heat.

The deep blue color of the water in the center of the pool results from a light-absorbing overtone of the hydroxy stretch of water [6]. Though this effect is responsible for making all large bodies of water blue, it is particularly intense in Grand Prismatic Spring because of the high purity and depth of the water in the middle of the spring.

[physical structure]
The spring is approximately 250 by 300 feet (75 by 91 m) in size and is 160 feet (49 meters) deep. The spring discharges an estimated 560 gallons (2000 litres) of 160°F (71°C) water per minute.[7]


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from: Life at high temperatures

What Makes the Colors?

The colors of the Yellowstone thermal features are justly famous. They were first mentioned by Osborne Russell, a trapper who spent the years 1834-1843 in the Yellowstone region. Viewing what is now called Grand Prismatic Spring, Russell noted: "The steam which arose from it was of three distinct colors. From the West side for one third of the diameter it was white, in the middle it was pale red, and the remaining third on the East light sky blue. Whether it was something peculiar in the state of the atmosphere.. or whether it was some chemical properties contained in the water... I am unable to say and shall leave the explanation to some scientific tourist who may...visit this place in the future."
What causes these colors? In Grand Prismatic spring, and others of similar character, the orange color is due to pigmented bacteria of the microbial mats, and the blue color to refracted skylight. The principal pigment for photosynthesis is chlorophyll, which is green. However, chlorophyll is sometimes masked by carotenoids, pigments related to vitamin A, which are orange, yellow, or red. Carotenoids protect the cells from the bright sunlight that occurs in Yellowstone, especially during the summer.

The color of a mat depends principally upon the ratio of chlorophyll to carotenoids. In the summer the chlorophyll content is often low, so that the microbial mats appear orange, red, or yellow. In the winter, the mats are usually dark green, because at this time of year the sunlight is subdued and chlorophyll dominates over carotenoids. In fact, even a few cloudy days in mid-summer can lead to an increase in chlorophyll and a darkening of the mats.

Thus, it is not just the kinds of bacteria but the response they make to sunlight that determines the colors.