Page 126 - Social Studies 7

Lesson Climate Change and Its Effects
5. 5

According to the Pollution Index 2016 Kathmandu is the
FACTS fourth topmost polluted city in the world and second
to Understand top most polluted city in Asia with 96.38 Pollution Index
score.

Climate refers to the average weather condition of a certain place over a period of
time. The main elements of climate are temperature and precipitation. Climate
remains constant for a considerable period of time whereas weather changes
frequently, for example, if it is sunny in the morning, then it can be raining in the
afternoon and cloudy in the evening. This is called weather. Climate remains for
a long period.

At present, climate is changing fast because of rising of temperature, increasing
of greenhouse gases (CFC gases), because of smoke released from factories,
industries, vehicles, houses, etc.

The significant change in the average weather in due course of time on the earth
or in any parts of it due to the irregularity in atmospheric temperature, wind,
rainfall, etc. is called climate change. This is mainly due to the rise in temperature
of the atmosphere. It causes negative effects in the atmosphere due to the excessive
use of petroleum products, coal, chemicals, firewood, etc.

Many greenhouse gases like carbon dioxide, nitrogen, methane, sulphur dioxide,
chlorofluro carbon, etc. emitted from the industries can trap the heat from the
sun. All these gases form a layer in the atmosphere which absorbs more heat.
This results in the rise in temperature worldwide. This is called global warming.
The global warming causes adverse effects in the form of irregular and unusual
rainfall, melting snow and rising coastline.

The greenhouse effect is the trapping of heat in the earth's atmosphere. It raises
the temperature of the atmosphere because the heat that comes through sun rays
in the earth's surface cannot reflect as it is absorbed by greenhouse gases.

Effects of Climate Change

The effect of climate change is seen everywhere. Nepal is also not away from the
effect of climate change. The temperature of Nepal is also increasing gradually.
There is not much cold in winter as it used to be in the past and number of
mosquitoes also increased. Some of the various impacts of climate change are
given below:

Dynamic Social Studies and Population Education - Book VII 126