Friday, 28 October 2016

PLANET EARTH

Up to two thirds of the earth's rocky surface is covered by water.It is covered by a mixture of gases called atmosphere reaching 700 kilometers from earth's surface.

  • Earth spins around it's poles
  • The spinning earth acts like a magnet.
  • The different parts of the earth are - the thin rocky crust- the solid middle mantle- a central core.Outer part of core is liquid.Inner core solid metal.
  • The inner core is made mainly of iron and nickel.The temperature at the core is 6000 degree Celsius, hot enough to melt metals.The core is 2500 kilometers wide.
  • Around the centre flows a hot liquid layer of iron and nickel.This is the outer core,2200 metre thick.
  • As the earth spins the metal ball and liquid layer move at different speeds.Due to extreme pressure in the intensely hot inner core is solid.
  • The largest part of eartth's layer is called mantle which is 2900 kms thick. It is made of slow moving  rock.
  • Rocks in the upper mantle is comparable to the paste oozing out of the tooth paste tube when you squeeze it.
  • Earth's surface is covered by crust.
  • Land is made up of continental crust which is 20 kilometers to 70 kilometers thick.
  • Most of the crust is made of granite.
  • Ocean bed is made up of 8 kilometer thick oceanic crust.It is mainly made of a rock called basalt.
  • The crust is divided into huge slabs of rock called plates.Most plates have land and seas on top of them.
  • Pacific plate is mostly covered by water.
  • Areas of land on the plates are called continents. 
  • Africa,Asia,Europe,North America,South America,Oceania,and Antarctica are the 7 continents.
  • Very,very slowly ,the continents are moving.
  • As plates move so do the continents.In some places plates push into each other.
  • The continents are moving very very slowly.As plates move so do the continents.
  • In some places plates push into each other.At times they move apart.North America is moving 3 cms away from Europe every year.
  • There are places on earth, where hot,liquid rocks shootup through it's  surface.There are volcanoes.The huge space beneath a volcano filled with molten rock is  called Magma chamber.
  • As pressure builds up inside the chamber ash,steam,and molten rock(lava) erupts to the surface.
  • Volcanoes erupt in different ways and have different shapes.Volcanoes like those in Hawai have running lava.Others have thick lava.
  • There are volcanoes under the sea.The hot lava cooled quickly by the sea forms pillow shaped lumps called pillow lava.
  • The hot rocks don't always reach the surface.Huge lumps become struck.These are called batholiths.
  • Rocks cool slowly forming large crystals called granite.
  • A geyser can be found on the top of some old volcanoes.If these volcanoes collapse the gaps between the broken rocks make a group of pipes and chambers.Rain water seeps in ,collecting in the chamber where it is heated untill it boils.
  • Steam builds up, pushing the water through the pipes and out of a cone shaped opening called nozzle.Steam and water shoot through the nozzle, making a fountain up to 60 meters high.
  • There are springs in the ocean.They are called black smokers.
  • They form near rift volcanoes.Here water is heated by volcanoes' magma chambers.The hot water dissolves chemicals in the rocks, which turn black when they are cooled by surrounding clean water.They rise like clouds of smoke from chimneys.
GEYSERS
Geysers are common in the volcanic regions of New Zealand in Oceania.In some areas they are even used to help make electricity.
In a hot spring, the water bubbles gently into the surface.
Wallowing in a mud spot can make your skin soft and smooth.Mud pot is made when fumes break down rocks into tiny pieces.These mix with water to form mud making it bubble .Some mud pots are cool enough to wallow in.
rocks being broken down by ice 
Ice has the power to make rocks crumble.In cold weather rainwater gets into cracks in rocks and freezes.Water swells as it turns into ice.The ice pushes with such power that the rock opens up the rock.Over a long time a rock can be broken down to thousands of tiny pieces.
Living things can break down rocks.Seeds landed on rocks grows and it"s roots smash open the rock.Tiny living things called lichens dissolve the surface of rocks to reach minerals they need to live.Rabbits make burrows which break up some of the rock in the ground.
Warming up and cooling down can break rocks into flakes.

  • when a rock warms up it swells a little.when it cools the rock shrink back to it"s original size.
  • repeated swelling and shrinking cause some rocks to break up into flakes.Sometimes layers of flakes form on a rock and make it look like onion skin.
  • Glaciers break up rocks and carry them away.They slide away down mountainside and melt.As glacier moves,some rocks are snapped off and carried along.
  • Rocks in rivers and seas are always getting smaller.As the water flows it gradually wears the rock down.Water also dissolves minerals from the rock.Sand and grit slowly grind away the rock surfaces.
FOREST FACTS 
The speed at which forests are being cut down worldwide is slowing down from 8.3 million hectares  a year in 1990 - 2000 to 5.2 million in the past decade(2001- 2010).
Forests help us to breathe.They pump out oxygen and absorb carbon dioxide.One adult leafy tree can produce as much oxygen as 10 people inhale in a year.Plankton are more prolific ,providing half of earth's  oxygen .But forests are key source of breathable air.
Half of all known species live in forests.This includes 80% of biodiversity on land.Bugs and worms' works provide nutrients into the soil.Bees and birds spread pollen and seeds.Keystone species like wolves and big bats keep hungry herbivores in check.
Each minute 85 acres of forests are destroyed

Saturday, 15 October 2016

TODAY(OCTOBER 16) IS WORLD FOOD DAY
The global message for World Food Day 2016 is “Climate is changing. Food and agriculture must too.”
It resonates with the crucial time in which the day will be observed, just before the next UN Climate Change Conference, COP 22, from 7-18 November 2016 in Marrakech, Morocco.
One third of food produced world over is wasted.More than 2 billion are living without food.

Saturday, 20 August 2016


  • when the forest disappears, there is no regulation of the flow into rivers. As a result, flood and droughts alternate in the affected  areas.
  • Mrine ecosystems support more than 660 million jobs jobs globally and are significant source of protein, particularly in developing countries. 
Many forests have been affected by acid deposition originating from industries.
Pesticide spraying to control insects leads to poisoning all the way up to the food chain and unintended loss of predatory hawks,owls,eagles.In the absence of predators pests flourish.
Oil exploration and military activities disrupt the ecosystem,contaminate areas, and lead to decline of species.
Over the past 30 years forest temperatures have risen 2 degree Celsius,and studies indicate that climate warming is the driving force behind the collapse of the forest's food-web.The impact of climate change on tropical ecosystems may be much greater than currently anticipated.

Sunday, 7 August 2016

Earth Overshoot Day

In less than 8 Months, Humanity exhausts Earth's budget for the year
Earth Overshoot Day 2016 lands on August 8, marking the date when humanity has exhausted nature’s budget for the year. For the rest of the year, we will maintain our ecological deficit by drawing down local resource stocks and accumulating carbon dioxide in the atmosphere. We will be operating in overshoot.
Just as a bank statement tracks income against expenditures, Global Footprint Network measures humanity’s demand for and supply of natural resources and ecological services. And the data is sobering. Global Footprint Network estimates that approximately every eight months, we demand more renewable resources and C02 sequestration than what the planet can provide for an entire year.

Thursday, 4 August 2016

The strangest chemical in the Universe - water.
All life needs liquid water(H2O).Water is the scaffold,the chemistry of life.

Wednesday, 27 July 2016

Air Quality
As urban air quality declines, the risk of stroke,heart disease,lung cancer,and chronic and acute respiratory diseases,including asthma, increases for the people who live in them.
Air pollution kills 6.5 million people every year globally.

Friday, 22 April 2016

TODAY IS EARTHDAY 2016

Earth supports all life forms.Provides air,water and food for all living things.Without plants no life can exist.Plants are the oxygen producing centres.So this year's Earth Day theme is to plant 7.8 billion trees by 2020.Let us fulfill this great task.Make life possible.