Category Ecology

OCEANS AND SEAS ARE DIFFERENT?

The difference lies in their depth, area and variety of marine life. An ocean is deeper and covers a greater area as compared to the sea. On the other hand, a sea has more diverse plant and animal life. There are fewer plants in an ocean as there are large areas where sunlight does not penetrate. The deep-sea creatures found in the darkness of oceans are unique.

 

                          Sea

Ocean

Sea is also made up of salty water but is smaller in size compared to oceans.

Ocean covers approximately 70% of the earth’s total surface. Ocean is made up of salty water.

The largest sea is the Meditteranean Sea. The area of Meditteranean sea is approximately 1.14 million square miles.

The largest Ocean is the Pacific Ocean with an area of approximately 60 million square miles. The smallest Ocean is the Arctic Ocean covering an area of 5.4 million square miles.

Seas are usually located close to land.

Oceans are not necessarily located close to land.

Aquatic life exists in abundance in seas as seas are usually located close to the Land.

Oceans have reduced aquatic life as it is far away from the land and deeper than the Seas.

There is a large quantity of marine life in the Seas as sunlight is able to penetrate deeper into the seas, allowing photosynthesis.

The marine life in oceans is usually confined to bacteria, shrimp, microscopic planktons. This is due to lack of penetration of sunlight deep into oceans thus not giving much scope for photosynthesis.

Some of the major seas are Mediterranean Sea, Carribean Sea, South China Sea, Black Sea etc. The deepest sea is Carribean Sea with an approximate depth of 6900 metres.

The Deepest Ocean is Pacific Ocean which is around 10,000 metres deep and the Arctic Ocean is around 5600 metres deep.

Credit: BYJU’S

Picture Credit : Google

Do Trees Die of Old Age?

While humans and animals stop producing new tissues over time – which is part of the ageing process – there’s no evidence to prove that this happens in trees. Due to this regenerative aspect, scientists believe trees actually have the ability to live indefinitely. But before that can happen, several external factors such as climate variation, storms, animal or insect attack, logging. accidents such as lightning, etc. cost them dearly. Despite these, some trees have managed to live for thousands of years. Among them is the Great Basin bristlecone pine tree in California, the U.S., which has celebrated about 5,000 birthdays!

When animals senesce, or grow older, their cells may cease to divide, or the division process may grow increasingly sloppy, leading to deleterious mistakes. On the outside, this aging process shows through cognitive decline, or wrinkles in humans. One animal in particular, the hydra, actually doesn’t seem to senesce. For all intents and purposes, it is biologically immortal.

While it’s not precisely known whether or not individual trees are biologically immortal in the same fashion, they definitely don’t grow old the same way animals do. Trees grow indeterminately, meaning that with the right conditions, they can grow and grow and grow, with only the laws of physics limiting their height. (There’s a certain point where a tree cannot send enough water from the roots to the top layer of leaves, preventing adequate photosynthesis.) Amazingly, once they hit that maximum height, instead of growing taller, they grow wider! And they do so at an ever-increasing rate! That’s right, trees actually grow faster as they age. Scientists reported this amazing finding in the journal Nature earlier this year, after examining the growth of over 700,000 trees worldwide.

While it’s not yet known precisely why trees grow faster as they age, the secret to their perpetual growth has already been revealed. Most plant cells are perpetually embryonic, meaning they can change into another cell type at any time.

Credit : Real Clear Science

Picture Credit : Google 

What is diamond planet?

Imagine walking on a planet that is full of diamond. Dubbed 55 Cancri e, an exoplanet twice the size of Earth, is composed of carbon mostly in the form of graphite and diamond. At least a third of the planet’s mass is likely diamond as a result of the temperatures and pressures in the planet’s interior. Further observations are necessary to confirm the nature of the planet. It orbits a Sun-like hot star called 55 Cancri A. Planets like this are vastly different from our Earth, which has relatively less carbon.

Astronomers discovered the planet in 2004 after looking at the spectrum of its parent star, 55 Cancri A, one of two stars in a binary system about 40 light-years from Earth in the constellation Cancer. There are at least four other planets in the same system, mostly discovered before 55 Cancri e. The team (led by the University of Texas at Austin’s Barbara McArthur) discovered subtle tugs on the parent star that could be explained by the presence of yet another planet. While the planet’s existence was challenged by a second research team in 2005, a separate team in 2006 confirmed it. 

Astronomers initially thought 55 Cancri e (abbreviated 55 Cnc e) had an orbital period of 2.8 days, but measurements in 2011 showed that the planet is much closer to its parent star. Observations with Canada’s MOST (Microvariability & Oscillations of STars) space telescope demonstrated an orbital period of less than 18 hours. Researchers estimated the surface temperature of 55 Cancri e could be as high as 4,892 F (2,700 C). 

Follow-up observations with the Spitzer Space Telescope in 2012 showed that 55 Cancri e is much weirder than anticipated. While original estimates said the planet was dense and rocky, Spitzer suggested the planet includes a healthy proportion of light elements and compounds (such as water). However, the planet’s high surface temperatures contribute to a “supercritical” fluid state, the researchers said, meaning that the gases are in a liquid-like state. 

Credit : Space.com

Picture Credit : Google 

 

Is Meghalaya the wettest place on Earth?

Mawsynram in Meghalaya is the wettest place, based on rainfall in the world. Located in the Khasi Hills, it receives about 11,872mm (nearly 467 inches) of average annual rainfall According to the Guinness Book of World Records, the region received 26,000mm of rainfall in 1985. The mountainous terrain of Mawsynram and the nearby Cherrapunji, the second wettest place, are known for their lush greenery and scenic beauty The “living bridges are one of the most beautiful features of this region. These have been created by the local people by training the roots of rubber trees into natural bridges. With the root systems constantly growing, these bridges are self-sustaining.

Primarily due to the high altitude, it seldom gets truly hot in Mawsynram. Average monthly temperatures range from around 11 °C in January to just above 20 °C in August. The village also experiences a brief but noticeably drier season from December until February, when monthly precipitation on average does not exceed 30 millimetres (1.2 in). The little precipitation during the village’s “low sun” season is something that is shared by many areas with this type of climate.

Three reasons can be cited for high rainfall at Mawsynram:

The warm moist winds of the northward-moving air from the Bay of Bengal during the monsoon, which cover an extensive area but are forced to converge into the narrower zone over the Khasi Hills, thus concentrating their moisture.
The alignment of the Khasi Hills (east to west) places them directly in the path of the airflow from the Bay of Bengal, producing a significant uplift (plus cooling, further condensation and thus more rain).
Finally, uplift over the Khasi Hills is virtually continuous in the monsoon period because the lifted air is constantly being pulled up by vigorous winds in the upper atmosphere; hence, the rainfall is more or less continuous.

Credit : Wikipedia 

Picture Credit : Google 

WHAT IS THE DIFFERENCE BETWEEN RAIN AND PRECIPITATION?

When a lot of water vapour fills the air, it begins to change and condense into droplets of water. These droplets fall back onto Earth as precipitation, which can take many forms – rain, hail, snow, sleet, fog, dew. So rain is just one form of precipitation.

The difference between Rainfall and Precipitation is that the Rainfall is a liquid water in the form of droplets that have condensed from atmospheric water vapor and then precipitated and Precipitation is a product of the condensation of atmospheric water vapour that falls under gravity.

Rainfall

Rain is liquid water in the form of droplets that have condensed from atmospheric water vapor and then becomes heavy enough to fall under gravity. 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.

The major cause of rain production is moisture moving along three-dimensional zones of temperature and moisture contrasts known as weather fronts. If enough moisture and upward motion is present, precipitation falls from convective clouds (those with strong upward vertical motion) such as cumulonimbus (thunder clouds) which can organize into narrow rainbands. In mountainous areas, heavy precipitation is possible where upslope flow is maximized within windward sides of the terrain at elevation which forces moist air to condense and fall out as rainfall along the sides of mountains. On the leeward side of mountains, desert climates can exist due to the dry air caused by downslope flow which causes heating and drying of the air mass. The movement of the monsoon trough, or intertropical convergence zone, brings rainy seasons to savannah climes.

The urban heat island effect leads to increased rainfall, both in amounts and intensity, downwind of cities. Global warming is also causing changes in the precipitation pattern globally, including wetter conditions across eastern North America and drier conditions in the tropics. Antarctica is the driest continent. 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). Climate classification systems such as the Köppen classification system use average annual rainfall to help differentiate between differing climate regimes. Rainfall is measured using rain gauges. Rainfall amounts can be estimated by weather radar.

Rain is also known or suspected on other planets, where it may be composed of methane, neon, sulfuric acid, or even iron rather than water.

Precipitation

In meteorology, precipitation is any product of the condensation of atmospheric water vapor that falls under gravity. The main forms of precipitation include drizzle, rain, sleet, snow, graupel and hail. Precipitation occurs when a portion of the atmosphere becomes saturated with water vapor, so that the water condenses and “precipitates”. Thus, fog and mist are not precipitation but suspensions, because the water vapor does not condense sufficiently to precipitate. Two processes, possibly acting together, can lead to air becoming saturated: cooling the air or adding water vapor to the air. Precipitation forms as smaller droplets coalesce via collision with other rain drops or ice crystals within a cloud. Short, intense periods of rain in scattered locations are called “showers.”

Moisture that is lifted or otherwise forced to rise over a layer of sub-freezing air at the surface may be condensed into clouds and rain. This process is typically active when freezing rain occurs. A stationary front is often present near the area of freezing rain and serves as the foci for forcing and rising air. Provided necessary and sufficient atmospheric moisture content, the moisture within the rising air will condense into clouds, namely stratus and cumulonimbus. Eventually, the cloud droplets will grow large enough to form raindrops and descend toward the Earth where they will freeze on contact with exposed objects. Where relatively warm water bodies are present, for example due to water evaporation from lakes, lake-effect snowfall becomes a concern downwind of the warm lakes within the cold cyclonic flow around the backside of extra tropical cyclones. Lake-effect snowfall can be locally heavy. Thunder snow is possible within a cyclone’s comma head and within lake effect precipitation bands. In mountainous areas, heavy precipitation is possible where upslope flow is maximized within windward sides of the terrain at elevation. On the leeward side of mountains, desert climates can exist due to the dry air caused by compressional heating. Most precipitation occurs within the tropics and is caused by convection. The movement of the monsoon trough, or inter-tropical convergence zone, brings rainy seasons to savannah climes.

Precipitation is a major component of the water cycle, and is responsible for depositing the fresh water on the planet. Approximately 505,000 cubic kilometres (121,000 cu mi) of waterfalls as precipitation each year; 398,000 cubic kilometres (95,000 cu mi) of it over the oceans and 107,000 cubic kilometres (26,000 cu mi) over land. Given the Earth’s surface area, that means the globally averaged annual precipitation is 990 millimetres (39 in), but over land it is only 715 millimetres (28.1 in). Climate classification systems such as the Köppen climate classification system use average annual rainfall to help differentiate between differing climate regimes.

Precipitation may occur on other celestial bodies, e.g. when it gets cold, Mars has precipitation which most likely takes the form of frost, rather than rain or snow.

Credit: maindifference.net

Picture credit: Google