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The impact of climate change on the economy
Climate change has the potential to create a wide range of economic impacts. In all likelihood all sectors of the economy will be affected. Some impacts will gradually affect economic processes, such as the effect of increasing temperature on energy demand, whereas others may come as extreme events, such as sudden floods or forest fires. Impacts may be either negative or positive. For example, agriculture may become more productive or tourism may flourish in areas experiencing higher or lower temperatures. However, in a global level, the negative impacts will generally outweigh the economic benefits. Beside industry specific impacts, the economy as a whole may be at risk in certain areas due to an increase in sea level and an increase in runoff by rivers. Coastal zones usually contain large human populations and a high concentration of economic activities.
Flooding and extreme storm events may seriously disrupt economic activities and cause loss of produced capital. The same is true for areas adjacent to major river systems which may be subject to flooding when precipitation and overland flow increases.
Assessing the impact of climate change faces a fundamental challenge of complexity. The set of mechanisms through which climate may influence economic outcomes, positive or negative is extremely large and difficult to investigate. For example, a decrease in agricultural output or value added products may be induced by climate change. However, climate change is only one driver among many that will shape agriculture in future decades. Other factors, such as technological developments, socio-economic factors or other environmental issues could have a similar large impact.
1.2.3. Environment
It literally means “Surroundings” and may be defined as sum total of all external conditions and influences that affect living organisms. It comprises the
following (i) Atmosphere (ii) Hydrosphere (iii) Lithosphere and (iv) Biosphere. The term „atmosphere‟ is explained in subsequent para. Hydrosphere forms that part of
environment which contains water in the form of sea, oceans, rivers, lakes, ponds etc. It covers almost 75% of the earth‟s surface. Lithosphere is the solid component
of the earth consisting of soil, rocks, mountains etc. The uppermost part of the earth‟s crust contains weathered rocks as well as organic matter and is called soil.
This is also the storehouse of minerals and metallic ores. Biosphere is that part of the lithosphere, hydrosphere and atmosphere where living organisms interact with these
parts and thus live together. A number of natural cyclic process like oxygen, water, nitrogen etc. are taking place in the environment to keep a balance of different
materials present in the environment.
1.2.4. Atmosphere
To better understand the intricacies of the phenomenon of climate change and the global warming, one needs to know the structure and composition of the
atmosphere surrounded by the planet earth. Earth‟s atmosphere could be defined as the gaseous mass surrounded and retained by the earth through its
gravitational force. Earth‟s atmosphere is a cover of gases that extend to a height of about 1600 km above the surface of the earth and protect the life on earth from
harmful radiation of cosmic rays from the Sun. The atmosphere is divided into five layers, which are
(a) Troposphere
(b) Stratosphere or ozonosphere
(c) Mesosphere
(d) Thermosphere and
(e) Exosphere
1.2.4.1.1.Troposphere: It is the lowest layer on the earth‟s surface, which is otherwise called the boundary layer, having about 70 to 80% of the total mass
present in the atmosphere. The height of the layer varies from 7 to 20 km above sea level depending on the latitude and season. The weather occurs in this layer.
The air at the bottom of the layer will be warm and gets colder when the height increases. This layer contains about 79% nitrogen, 21% oxygen and only a small
concentration of other gases such as argon, Carbon Dioxide etc. Dust particles and water vapour are the other major components in this layer, of which water vapor
helps to form clouds. The sunlight warms the earth during day time and the heat is radiated from earth to the atmosphere. The warm air tends to rise in the atmosphere.
The top portion of the layer is colder.
1.2.4.2.Stratosphere: The second layer in the atmosphere is known as the stratosphere, which starts a 20 km and extends up to 50 km from the earth‟s surface.
There is a variation of about 8 to 16 km in the bottom of the layer due to the variation in latitude and seasons. The bottom portion of this layer is cooler and temperature
increases with the increase in height. This layer plays a vital role in keeping the life on earth as the ozone is abundantly available here. Ozone absorbs the Ultra-Violet
(UV) radiations from Sun. Increasing doses of UV radiations may cause skin cancer, eye cataracts, damage to the immune system in animals and human beings and
have an adverse impact on the plant growth. Ozone is scattered between 19 to 30 km in the upper layer of stratosphere. The Ozone is formed when the highly
energetic solar radiation strikes the molecules of oxygen and splits it into two atoms apart and the freed atoms conjoin with the oxygen through the process of
photolysis, which is a process whereby sunlight causes the chemical bonds in a molecule to break. Ozone is also naturally broken down by sunlight and by a chemical
reaction with various compounds containing nitrogen, hydrogen and chlorine. In a pristine atmosphere, there is a balance between the amount of ozone generated
and destroyed. The air is quite stable in the stratosphere. Air is thin and dry and no water vapour present in this region. Due to lack of vertical convection, the materials
got into this region stays longer periods. The Ozone depleting substances like CFCs could stay here and react with ozone, resulting in depletion in the amount of ozone.
1.2.4.3.Mesosphere: It is the third layer in the atmosphere which starts at 50 km from the earth‟s surface and goes up to 85 km. The bottom portion of the
mesosphere is hotter and the temperature gets colder when height increases. The upper layer of the mesosphere is the coldest with -900C. The air is so thin in this
region that the atoms and molecules of gases hardly ever run into each other. 1.2.4.4.Thermosphere: The fourth layer in the atmosphere is thermosphere. It starts
from 85 km to 500 km and extends up to 1000 km. This layer is very hot at about 5000C when the sun is active. A good amount of sun‟s X-ray and UV radiations were
absorbed in this area, making this region very hot. The temperature in the upper layer varies from 500 0C to 20000C or higher depending on the sun‟s activity. A
most common definition says that the space begins with thermosphere at an altitude of 100 km as the air is too thin in this region. The space shuttles and space
stations are orbiting around the earth in this region only.
1.2.4.5.Exosphere: It is the fifth layer having a very thin layer of air containing atoms and molecules only. These particles escape into the space from this region
only.
1.2.5 .Some Terminologies and Definitions
Precipitation
Precipitation refers to the quantity of water falling to the earth at a specific period of time. The water could be in any form like rain, snow, hail, sleet or mist.
Natural Carbon Sinks
Natural Carbon Sinks are the reservoirs which absorb the carbon and store it for indefinite period. Forests, oceans, soils and atmosphere are better examples of carbon sinks. The plants and other organisms that use photosynthesis to remove carbon from atmosphere by incorporating it into biomass are also carbon sinks.
Carbon Sequestration
This term refers to describing processes that remove carbon from atmosphere.
Biomass
In ecology, Biomass is defined as the mass of living biological organisms in a given area or ecosystem at a given time. This is a renewable energy source and is biological material derived from living or recently living organism such as wood, waste, hydrogen (gas) and alcohol fuels.
Carbon Stock
The quantity of carbon contained in a reservoir or a system which has the capacity to accumulate or release carbon. The forest biomass refers to the amount of carbon stored in the forest ecosystem, mainly in living biomass and soil, but to a lesser extent in dead wood and litter.
Anthropogenic Emission
These are the emissions of greenhouse gases resulting from human activities.
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