The Kerala red rain phenomenon was a blood rain event that occurred from 25 July to 23 September 2001, when heavy downpours of red-colored rain fell sporadically on the southern Indian state of Kerala, staining clothes pink. Yellow, green, and black rain was also reported. Coloured rain was also reported in Kerala in 1896 and several times since, most recently in June 2012, and from 15 November 2012 to 27 December 2012 in eastern and north-central provinces of Sri Lanka.
Following a light microscopy examination in 2001, it was initially thought that the rains were colored by fallout from a hypothetical meteor burst, but a study commissioned by the Government of India concluded that the rains had been colored by airborne spores from a locally prolific terrestrial green alga from the genus Trentepohlia. an international team later identified the exact species as T.annulata.
Occurrence:-
The colored rain of Kerala began falling on 25 July 2001, in the districts of Kottayam and Idukki in the southern part of the state. Yello, green, and black rain was also reported. May more occurrences of the red rain were reported over the following ten days, and then with diminishing frequency until late September. According to locals, the first colored rain was preceded by a loud thunderclap and flash of light, and followed by groves of trees shedding shriveled grey "burnt" leaves. Shriveled leaves and the disappearance and sudden formation of wells were also reported around the same time in the area. Typically fell over small areas, no more than a few square kilometers in size, and was sometimes sp localized that normal rain could be falling just a few meters away from the red rain. Red rainfalls typically lasted less than 20 minutes. Each milliliter of rainwater contained about 9 million red particles. Extrapolating these figures to the total amount of red rain estimated to have fallen, it was estimated that 50,000 kilograms (110,000 lb) of red particles had fallen on Kerala.
Description of the particles:-
The brownish-red solid separated from the red rain consisted of about 90% round red particles and the balance consisted of debris. The particles in suspension in the rainwater were responsible for the color of rain, which at times was strongly colored red. A small percentage of particles were white or had light yellow, bluish grey, and green tints. The particles were typically 4 to 10 µm across and spherical or oval. Electron microscope images showed the particles as having a depressed center.at still higher magnification some particles showed internal structures.
Chemical composition:-
Some water samples were taken to the Centre for Earth Science Studies (CESS) in India, where they separated the suspended particles by filtration. The pH of the was found to be around 7(neutral). The electrical conductivity of the rainwater showed the absence of any dissolved salts. Sediment (red particles plus debris) was collected and analyzed by the CESS using a combination of ion-coupled plasma mass spectrometry, atomic absorption spectrometry, and wet chemical methods. The major elements found are listed below. The CESS analysis also showed significant amounts of heavy metals, including nickel (43 ppm), manganese (59 ppm), titanium (321 ppm), chromium (67 ppm) and copper (55 ppm).
physicists Godfrey Louis and Santhosh Kumar of the Mahatma Gandhi University, Kerala, used energy disp[ersive X-ray spectroscopy analysis of the red solid and showed that the particles were composed of mostly carbon and oxygen, with trace amounts of silicon and iron. A CHN analyzer showed a content of 43.03% carbon, 4.43% hydrogen, and 1.84% nitrogen.
J.Thomas Brenna in the division of nutritional sciences at comell university conducted carbon and nitrogen isotope analyses, an elemental analyzer, and an isotope ratio (IR) mass spectrometer. The red particles collapsed when dried, which suggested that they were filled with fluid. The amino acids in the particles were analyzed and seven were identified (in order of concentration): phenylalanine, glutamic acid/glutamine, serine, aspartic acid, threonine, and arginine. the results were consistent with a marine origin or a terrestrial plant that uses a c4 photosynthetic pathway.
Government Report:-
Some water samples were taken to the Centre for Earth Science Studies (CESS) in India, where they separated the suspended particles by filtration. The pH of the was found to be around 7(neutral). The electrical conductivity of the rainwater showed the absence of any dissolved salts. Sediment (red particles plus debris) was collected and analyzed by the CESS using a combination of ion-coupled plasma mass spectrometry, atomic absorption spectrometry, and wet chemical methods. The major elements found are listed below. The CESS analysis also showed significant amounts of heavy metals, including nickel (43 ppm), manganese (59 ppm), titanium (321 ppm), chromium (67 ppm) and copper (55 ppm).
physicists Godfrey Louis and Santhosh Kumar of the Mahatma Gandhi University, Kerala, used energy disp[ersive X-ray spectroscopy analysis of the red solid and showed that the particles were composed of mostly carbon and oxygen, with trace amounts of silicon and iron. A CHN analyzer showed a content of 43.03% carbon, 4.43% hydrogen, and 1.84% nitrogen.
J.Thomas Brenna in the division of nutritional sciences at comell university conducted carbon and nitrogen isotope analyses, an elemental analyzer, and an isotope ratio (IR) mass spectrometer. The red particles collapsed when dried, which suggested that they were filled with fluid. The amino acids in the particles were analyzed and seven were identified (in order of concentration): phenylalanine, glutamic acid/glutamine, serine, aspartic acid, threonine, and arginine. the results were consistent with a marine origin or a terrestrial plant that uses a c4 photosynthetic pathway.
| Analysis by the CESS (%) | Analysis by Louis & Kumar (%) | |
|---|---|---|
| Al | 1.0 | 0.41 |
| Ca | 2.52 | |
| C | 51.00 | 49.53 |
| Cl | 0.12 | |
| H | 4.43 | |
| Fe | 0.61 | 0.97 |
| Mg | 1.48 | |
| N | 1.84 | |
| O | 45.42 | |
| K | 0.26 | |
| P | 0.08 | |
| Si | 7.50 | 2.85 |
| Na | 0.49 | 0.69 |
Government Report:-
Initially, the Center of Earth science studies (CESS) stated that the likely cause of the red rain was an exploding meteor, which had dispersed about 1,000 kg (one ton ) of material. A few days later, following a basic light microscopy evaluation, they CESS retracted this as they noticed the particles resembled spores, and because debris from a meteor would not have continued to fall from the stratosphere onto the same area while unaffected by wind.
A sample was, therefore, handed over to the Tropical Botanical garden and Research Institute (TBGRI) for microbiological Studies, where the spores were allowed to grow in a medium suitable for growth of algae and fungi. The inoculated Petri dishes and conical flasks were incubated for three to seven days and the cultures were observed under a microscope.
In November 2001, commissioned by the GOvernment of India's Department of science & Technology, the Center for Earth Science Studies(CESS) and the tropical botanical Garden and research institute (TBGRI) issued a joint report, which concluded.
The color was found due to the presence of a large amount spores of a lichen-forming alga belonging to the genus trentepohila field verification showed that the region had plenty of such lichens. Samples of lichen taken from changancherry area, when cultured in an alga growth medium, also showed the presence of the same species of both samples (from rainwater and from trees) produced the same kind of algae, indicating that the spores are seen in the rainwater most probably came from local sources.
The site was again visited on 16 August 2001 and it was found that almost all the trees, rocks and even lamp posts in the region were covered with Trentepoholia estimated to be ain sufficient amounts to generate the quantity of spores seen in the rainwater. Although red or orange, trentepohila is a chlorophyte green alga which can grow abundantly on tree brak or damp soil and rocks but is also the photosynthetic symbiont or photobiont of may lichens, including some of those abundant on the trees in changanassery area. The strong orange color of the algae, which masks the green of the chlorophyll, is caused by the presence of large quantities of orange carotenoid pigments. A lichen is not a single organism, but the result of a partnership(symbiosis) between a fungus and an alga or cyanobacterium.
The report also stated that there was no meteoric, volcanic or desert dust origin present in the rainwater and that its color was not due to any dissolved gases or pollutants. The report concluded that heavy rains in Kerala-in the weeks preceding the red rains-could have caused the widespread growth of lichens, which had given rise to a large quantity of spores into the atmosphere. However, for these lichens to release their reproductive phase at about the same time. The CESS report noted that while this may be a possibility, it is quite improbable. Also, they could find to the satisfactory explanation for the apparently extraordinary dispersal, nor for the apparent uptake of the spores into clouds. CESS scientists noted that "While the cause of the color in the rainfall has been identified, finding the answer to these questions is a challenge." Attempting to explain the unusual spore proliferation and dispersal, researcher Ian Goddard proposed several local atmospheric models.
Parts of the CESS/TBgri report were supported by Milton Wainwright at Sheffield University, who, together with Chandra Wickramasinghe, has studied stratospheric spores. In March 2006 Wainwright said the particles were similar in appearance to spores of a rust fungus, later saying that he had confirmed the presence of DNA, and reported their similarity to algal spores, and found no evidence to suggest that the rain contained dust, sand, fat, globules, or blood. In November 2012, Rajkumar Gangappa and Stuart Hogg from the University of Glamorgan, UK, confirmed that the red rain cells from Kerala contain DNA.
In February 2015, a team of scientists from India and Austria also supported the identification of the algal spores as Trentepohlia annulata, However, They speculate that the spores from the 2011 incident were carried by winds from Europe to the Indian subcontinent.
Phylogenetics:-
A study published in February 2015 established that the exact species of green microalgae is Tretephohlia annulata. The study used molecular phylogenetics to compare the evolution of DNA sequences of T.annulata isolated from colored rain samples with that of T.annulate from Austria. The results suggest that the isolate from Kerala is a recently introduced species from Austria. The researchers suggest that the introduction happened through clouds over the ocean - a phenomenon of intercontinental species dispersal previously reported of bacteria and fungi, but first time for the alga. How exactly these lower stratospheric clouds containing algal spores got to Kerala remains unknown.
Note:-
The data in this article was collected from some of the references on internet.
In November 2001, commissioned by the GOvernment of India's Department of science & Technology, the Center for Earth Science Studies(CESS) and the tropical botanical Garden and research institute (TBGRI) issued a joint report, which concluded.
The color was found due to the presence of a large amount spores of a lichen-forming alga belonging to the genus trentepohila field verification showed that the region had plenty of such lichens. Samples of lichen taken from changancherry area, when cultured in an alga growth medium, also showed the presence of the same species of both samples (from rainwater and from trees) produced the same kind of algae, indicating that the spores are seen in the rainwater most probably came from local sources.
The site was again visited on 16 August 2001 and it was found that almost all the trees, rocks and even lamp posts in the region were covered with Trentepoholia estimated to be ain sufficient amounts to generate the quantity of spores seen in the rainwater. Although red or orange, trentepohila is a chlorophyte green alga which can grow abundantly on tree brak or damp soil and rocks but is also the photosynthetic symbiont or photobiont of may lichens, including some of those abundant on the trees in changanassery area. The strong orange color of the algae, which masks the green of the chlorophyll, is caused by the presence of large quantities of orange carotenoid pigments. A lichen is not a single organism, but the result of a partnership(symbiosis) between a fungus and an alga or cyanobacterium.
The report also stated that there was no meteoric, volcanic or desert dust origin present in the rainwater and that its color was not due to any dissolved gases or pollutants. The report concluded that heavy rains in Kerala-in the weeks preceding the red rains-could have caused the widespread growth of lichens, which had given rise to a large quantity of spores into the atmosphere. However, for these lichens to release their reproductive phase at about the same time. The CESS report noted that while this may be a possibility, it is quite improbable. Also, they could find to the satisfactory explanation for the apparently extraordinary dispersal, nor for the apparent uptake of the spores into clouds. CESS scientists noted that "While the cause of the color in the rainfall has been identified, finding the answer to these questions is a challenge." Attempting to explain the unusual spore proliferation and dispersal, researcher Ian Goddard proposed several local atmospheric models.
Parts of the CESS/TBgri report were supported by Milton Wainwright at Sheffield University, who, together with Chandra Wickramasinghe, has studied stratospheric spores. In March 2006 Wainwright said the particles were similar in appearance to spores of a rust fungus, later saying that he had confirmed the presence of DNA, and reported their similarity to algal spores, and found no evidence to suggest that the rain contained dust, sand, fat, globules, or blood. In November 2012, Rajkumar Gangappa and Stuart Hogg from the University of Glamorgan, UK, confirmed that the red rain cells from Kerala contain DNA.
In February 2015, a team of scientists from India and Austria also supported the identification of the algal spores as Trentepohlia annulata, However, They speculate that the spores from the 2011 incident were carried by winds from Europe to the Indian subcontinent.
Phylogenetics:-
A study published in February 2015 established that the exact species of green microalgae is Tretephohlia annulata. The study used molecular phylogenetics to compare the evolution of DNA sequences of T.annulata isolated from colored rain samples with that of T.annulate from Austria. The results suggest that the isolate from Kerala is a recently introduced species from Austria. The researchers suggest that the introduction happened through clouds over the ocean - a phenomenon of intercontinental species dispersal previously reported of bacteria and fungi, but first time for the alga. How exactly these lower stratospheric clouds containing algal spores got to Kerala remains unknown.
Note:-
The data in this article was collected from some of the references on internet.
Comments
Post a Comment