Green Revolution and its impact on major crops of India

  The Green Revolution was initiated in the 1960’s to address the issue of malnutrition in the developing world. The technology of the Green Revolution involved bio-engineered seeds that worked in conjunction with chemical fertilizers and heavy irrigation to increase crop yields. Green Revolution was largely confined in wheat crop and in northern India such … Read more Green Revolution and its impact on major crops of India

Drainage Systems Himalayan and the Peninsular

  Drainage: Flow of water through well-defined channels. Network of such channels is called a drainage system . Drainage basin: An area drained by a river and its tributaries. Watershed: Boundary line separating one drainage basin from other. River basins are larger watersheds. Drainage pattern of an area depends on the geological time period, nature … Read more Drainage Systems Himalayan and the Peninsular

Structure, relief and physiographic divisions

  Three Geological divisions: The peninsular block The Himalayas and other Peninsular Mountains Indo-Ganga-Brahmaputra Plain   Peninsualar block is made of gneisses (metamorphic) and granites (igneous). Six physiographic divisions: The Northern and North-eastern Mountains The Northern Plain The Peninsular Plateau The Indian Desert The Coastal Plains The Islands Northern and North-Eastern Mountains Approximate length of … Read more Structure, relief and physiographic divisions

 Climatic changes

    It is the long term change in the statistical distribution of weather patterns over periods of time Though it has been happening naturally for millions of years, in recent years it has accelerated due to anthropogenic causes and has been causing global warming. UNFCCC defines climate change as – “a change of climate … Read more  Climatic changes

 Global warming

  An increase in the average temperature of Earth’s near surface air and oceans since the mid-20th century 4th assessment report of IPCC: global temperature increased 74+0.18 degree C during the 20th century. Caused by greenhouse gases Water vapour, Co2, Methane, Nitrous Oxide, Ozone, CFCs (in order of abundance) Since the industrial revolution, the burning of fossil fuels has increased … Read more  Global warming

Greenhouse effect

  The greenhouse effect is a natural process that warms the Earth’s surface. When the Sun’s energy reaches the Earth’s atmosphere, some of it is reflected back to space and the rest is absorbed and re-radiated by greenhouse gases. It is the process by which radiation from a planet’s atmosphere warms the planet’s surface to a … Read more Greenhouse effect

Classification of climates, (Koppen and Thornthwaite)

  Climatic Regions of India : Koeppen’s Classification Climate Type Climatic Region Annual Rainfall in the Region Amw (Monsoon type with shorter dry winter season) Western coastal region, south of Mumbai over 300 cm As (Monsoon type with dry season in high sun period) Coromandel coast = Coastal Tamil Nadu and adjoining areas of Andhra Pradesh … Read more Classification of climates, (Koppen and Thornthwaite)

Tropical and temperate cyclones

    The atmospheric disturbances which involve a closed circulation about a low pressure centre, anticlockwise in the northern atmosphere and clockwise in the southern hemisphere are called cyclones. They fall into the following two broad categories: (a) Extra-tropical or Temperate and (b) tropical cyclones. (a) Temperate Cyclones Temperate cyclones are formed along a front … Read more Tropical and temperate cyclones

 Air masses and fronts

  Airmasses   An airmass is a large body of air with relatively uniform thermal and moisture characteristics. Airmasses cover large regions of the earth, typically several hundred thousand square kilometers. Airmasses can be as deep as the depth of the troposphere or as shallow as 1 to 2 km. Airmasses form when air remains … Read more  Air masses and fronts