Where it rains sulfuric acid, why some rain never hits the ground, and more facts you never knew about the wet stuff that falls from the sky.
The least rainy place on earth isn’t in the desert
It may be covered with ice, but Antarctica gets only 6.5 inches of rain or snow per year, making it the continent with the lowest annual rainfall by far. On the other end of the spectrum, Lloro, Colombia, absorbs more than 500 inches of rainfall per year. North America is relatively dry by comparison, collecting 256 inches of rain annually. Find out some old wives’ tales about weather that just aren’t true.
Rain doesn’t always make the ground wet
In dry, hot places, rain sometimes evaporates before it hits the ground. Environmentalist Edward Abbey describes “phantom rain” this way: “You see curtains of rain dangling in the sky while the living things wither below for want of water. Torture by tantalizing, hope without fulfillment. Then the clouds dissipate into nothingness.”
Not all raindrops are made of water
On Venus, and other moons and planets, rain is made of sulfuric acid or methane. Even stranger: On a planet 5,000 light years away, scientists found raindrops made of iron rather than water. For more watery wisdom, check out these facts you never knew about Earth’s oceans.
There’s a scientifically proven way to get less wet in the rain
Run! As Henry Reich, the brains behind the YouTube Channel MinutePhysics, explains, the faster you get out of the rain, the drier you’ll be, regardless of the additional raindrops you run into. And if you’re looking for something to keep you dry, here are the best umbrellas for a rainy day.
The shape and color of clouds can help you predict rain
Generally speaking, if you see a cumulonimbus cloud (a tall, puffy cloud that looks flat at the top), or a nimbostratus cloud (a flat low-level gray cloud), you can be fairly certain that rain is in the 24-hour forecast. Find out more ways to predict the weather just by looking at the clouds.
There’s a reason you love the smell of rain
Water doesn’t smell like anything, so why does rain produce a pleasant aroma after it falls? Well, it’s because of a molecule, called geosmin, created by soil-dwelling bacteria. When rain falls, it creates air pockets, which contain small amounts of geosmin. The rain traps and then releases these air pockets, dispersing geosmin into the air, where it’s free to travel to human sniffers. The smell of rain even has a name: “Petrichor.” Learn some surprising facts you never knew about lightning, too.
It’s not actually “drop”-shaped
The “raindrop” designation is actually a misnomer, since scientists have concluded that rain is not actually shaped like a teardrop. When water molecules condense and bind together in the atmosphere before falling, they form a more-or-less spherical shape. As they fall, they encounter air pressure, flattening the bottom of the drops, so that they end up taking on a shape more like a hamburger bun.
The United States record for 24-hour rainfall was just broken
In a single day in July 1979, Tropical Storm Claudette dropped a whopping 43 inches of rain on a small Texas town called Alvin. Alvin, which is just south of Houston, held the record for the most rainfall in the United States in 24 hours—until 2018. In April of that year, a rain gauge in the Hawaiian town of Hanalei recorded 49.69 inches of rainfall in one day.
Rain is money
In the African nation of Botswana, the currency is the Botswanan pula. The word “pula,” though, also means “rain,” and its use as the name of the primary currency demonstrates just how rare and precious rain is in this sub-Saharan country.
It’s been raining a long time
Scientists have discovered fossils containing indentations of raindrops dating back as far as 2.7 billion years ago. According to Scientific American, the early liquid rain fell on layers of ash from volcanic eruptions, and then more ash fell on top, preserving the miniature craters from the raindrops. Interestingly, it was erosion created by more rain that exposed the rain fossils for modern study.
Rain is the result of water vapor condensing and precipitating, forming droplets that fall from clouds due to gravity.
There are always water vapor in the air. Warm air has more water vapor than cold air, which is why it is often humid in the summer.
The vapor becomes small water droplets or ice crystals. When enough of these droplets collect together, we see them as clouds. If the clouds are big enough and have enough water droplets, the droplets bang together and form even bigger drops. When the drops get heavy, they fall because of gravity, and you see and feel rain.
Majority of us think raindrops look like teardrops; they truly look more like the top half of a hamburger bun, flattened on the bottom and with a curved dome top. Smaller drops are called cloud droplets, and their shape is spherical.
Not all raindrops are created equal. The size of falling raindrops depends on several factors, including where the cloud producing the drops is located on the globe and where the drops originate in the cloud.
Raindrops have sizes ranging from 0.1 to 9 millimeters (0.0039 to 0.3543 inch) mean diameter, above which they tend to break up.
At sea level and without wind, 0.5 mm (0.020 in) drizzle impacts at 2 m/s (6.6 ft/s) or 7.2 km/h (4.5 mph), while large 5 mm (0.20 in) drops impact at around 9 m/s (30 ft/s) or 32 km/h (20 mph).
The globally averaged annual precipitation over land is 715 mm (28.1 in), but over the whole Earth it is much higher at 990 mm (39 in).
By average annual rainfall, the wettest place is Mawsynram, Meghalaya, India, with 11,873 millimeters (467 inches) of rain per year. Meghalaya means ‘land of the clouds’. Most of the rain occurs during the monsoon season, between June and September.
The highest amount of rainfall ever recorded in one year is 22,987 mm (905.0 in) in Cherrapunji, India in 1861.
The highest amount of rainfall ever recorded in 24 hours is 182.5 centimeters (71.9 inches) in Foc-Foc, La Réunion. This occurred during tropical cyclone Denise on January 8, 1966.
Antarctica is the driest continent on Earth.
Each second, approximately 16 million tons of water evaporates from the surface of the Earth. This 16 million tons of water is the same amount in raindrops that falls back to Earth each second. Water moves continuously in a balanced cycle based on its volume.
Rain is a major component of the water cycle and is responsible for depositing most of the fresh water on the Earth.
It provides suitable conditions for many types of ecosystems, as well as water for hydroelectric power plants and crop irrigation.
Forests that experience high levels of rainfall are called rainforests.
Rain droplets contain dissolved nitrogen that comes from the air. This free and natural fertilizer makes grass look greener after rainfall.
Petrichor is the earthy scent produced when rain falls on dry soil. The word is constructed from Greek petra, meaning “stone”, and ichor, the fluid that flows in the veins of the gods in Greek mythology.
Rain can begin as snow, but by the time it reaches the Earth’s surface, it has melted because the temperature closer to Earth is warmer.
In certain conditions precipitation may fall from a cloud but then evaporates or sublimes before reaching the ground. This is termed virga and is more often seen in hot and dry climates.
Phenomenon of Yoro Fish Rain is just too weird and looks like a hoax – but it is not! The fish rain takes place in the beginning of rainy period somewhere in May – July. It is not known when this phenomenon started – first reports are from the middle of 19th century, when first missionary Father Subirana came here.
Blood rain or red rain is a phenomenon in which blood is perceived to fall from the sky in the form of rain. Cases have been recorded since Homer’s Iliad, composed approximately 8th century BC, and are widespread. Before the 17th century it was generally believed that the rain was actually blood. There is now a scientific consensus that the blood rain phenomenon is caused by aerial spores of green microalgae Trentepohlia annulata. Yellow, green, and black rain was also reported.
Rain with high levels of acid (a low pH) is called acid rain. Caused by the release of sulphur dioxide and nitrogen oxides into the air (often from factories and power stations), it can be harmful to plants and animals.