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When I opened my curtains this morning and looked out onto my roof, I noticed that the rainwater, normally clear, had turned bright red (see photo). Does anyone have any clue as to what could have caused this colouration?
鈥� The most probable explanation is the presence of spores of , a lichen-forming alga. This alga can be found on tree bark, roofs, damp soil and even lamp posts. The colour would have been caused not by algal growth but by the release of spores. The photograph shows a ladder, trees nearby and some dry leaves, all of which could have favoured the growth of this lichen.
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This type of phenomenon has been recorded before, one of the most noted occasions being in 2001. From 25 July to 23 September that year, red rain sporadically fell on the south Indian state. Heavy downpours occurred in which the rain stained people鈥檚 clothes pink.
Vinod Kumar, Jaipur, Rajasthan, India
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