TNPSC Prelims and Mains Notes-TNPSC Test Series
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
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
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
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
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
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
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
The temperature is the measurement in degrees of how hot (or cold) a thing (or a place) is. The temperature of the atmosphere is not same across the Earth. It varies in spatial and temporal dimensions. The temperature of a place depends largely on the insolation received by that place. The interaction of insolation … Read more
The ultimate source of atmospheric energy is in fact heat and light received through space from the Sun. This energy is known as solar insolation. The Earth receives only a tiny fraction of the total amount of Sun’s radiations. Only two billionths or two units of energy out of 1,00,00,00,000 units of energy … Read more
An atmosphere is a layer of gases surrounding a planet or other material body, that is held in place by the gravity of that body. Many of the planets in this solar system have atmospheres, but none that we know of have an atmosphere quite like ours – one that can support life. The … Read more