By Nethmie Dehigama   Earth is a weird and wondrous place, home to many mysteries and intricacies. In this article, you will read about five different weather, water, and earthly phenomena that you have to read about if you love to know more about what our planet is hiding.   Frost flowers   These are ice crystals that appear on the ocean’s or lake’s surface when the air is frigid, and actually not a rare sight in the Arctic Ocean. It is very similar to frost that forms in any cold environment, and they tend to last up to two weeks as long as the winds and waters are calm. For these to form, the air must be dry and cold – colder than the surface of the water. We are talking -22°C. As the ice directly turns from ice into vapour, and if this vapour becomes oversaturated with liquid, as soon as it touches an ice crystal, the flowers begin to form. What is most surprising about these frosty blossoms is that each of them are home to millions of bacteria thriving in a much colder, saltier environment than what they are usually used to. Essentially, each flower becomes an ecosystem of its own, albeit short-lived.   Fairy circles If you had an aerial view of the sprawling grasslands of the Namibian desert, you would see a set of “spots”. These spots are known as fairy circles. They are circular barren areas surrounded by patches of arid vegetation or Stipagrostis grasses and can occur over thousands of kilometres. Local legends impart stories of gods leaving their heavenly footprints behind. Until the year 2014, this type of natural formation was thought to be only visible in Namibia, but scientists were alerted to similar formations in places like Pilbara in Western Australia. These patches are thought to form in monospecific vegetation, where conditions are arid. They seem to last up to 60 years. However, the reason behind their formation is still largely a mystery. One hypothesis suggests that it is the plants’ way of arranging themselves to access water, which is a scarce resource in these areas.   Fire rainbows   Scientifically known as circumhorizontal arcs, these optical phenomena occur when a type of halo is formed due to the refraction of light in plate-shaped ice crystals mixed in the atmosphere, occurring typically within cirrus clouds. In other words, there have to be special conditions present for the fire rainbows to appear. In fact, they can only be witnessed when the sun is 58 degrees above the horizon. The ice crystals in the atmosphere need to be hexagonal in shape with their faces parallel to the ground. I myself have seen a few circumhorizontal arcs, one which I distinctly remember – when we were leaving Yala after a safari in the evening. It’s just beautiful and peculiar to witness what looks like an oil spill except from a cloud.   Underwater river in Mexico If you’re looking for an interesting spot to go scuba diving, look no further than the underwater river in Mexico. But how can there be an underwater river? Well, it is more of an illusion. As limestone bedrock collapses (i.e., the floor of the cave where this river is present), it creates a pit. This pit subsequently fills with a mixture of groundwater and saltwater. Organic matter flows down to the trench, and when it decomposes, it produces a cloud of hydrogen sulphide that forms a halocline (if you read the article on blue holes previously, you would be familiar with this). This resembles a flowing body of water.   Mammatus clouds These look like pouches hanging from the base of a cloud, and in the past, people have taken these clouds as a sign that the sky is falling. Mammatus clouds are formed in association with large cumulonimbus clouds when there’s turbulence within the clouds. These clouds are known to bring in thunderstorms due to their huge mass of unstable air. It could even bring forth hail, snow, and lightning. Mammatus comes from the Latin word “mamma” which translates to “udder” or “breast”. Their striking appearance is most visible when the sun is low in the sky and their pouches are framed by the sunlight.   So, which of these phenomena have you witnessed? And which do you hope to see?   PHOTOS © ANATOLY BELOSCHIN, NASA, SCOTT CORDELL, MATTHIAS WIETZ, ROBERT HARDING, HOFIT KIM COHEN