Environmental Engineering Reference
In-Depth Information
Fig. 7.31
Effect of Haiyan on the coastal region of Philippines
and deforestation, also exert considerable in
u-
ence on the mangrove forests, seagrass bed, salt
marsh ecosystem and seaweeds that are the
dominant components of blue carbon. The major
anthropogenic factors that alter and influence the
coastal vegetation may be broadly classi
fl
dioxide levels are substantially higher now than
at any time in the last 750,000 years. Along with
rising methane levels, these changes are antici-
pated to cause an increase of atmospheric tem-
perature within 1.4
-
5.6
°
C between 1990 and
ed into
2100.
Fossil fuels are burnt to run the wheels of
industries. Cement manufacturing is one of the
largest causes of human-induced carbon dioxide
emissions. The gas is produced when calcium
carbonate (CaCO
3
) is heated to produce the cal-
cium oxide (CaO, also called
six broad headings.
A. Burning of fossil fuels
B. Modi
cation of land use pattern
C. Livestock
D. Development of coastal structures
E. Pollution
F. Construction of dams and barrages.
A. Burning of Fossil Fuels
Coal, oil and natural gas are collectively referred
to as fossil fuels because they are formed from
the remains of plants and microorganisms that
lived millions of years ago. Fossil fuels constitute
the backbone of modern civilization. Beginning
with the industrial revolution in the 1850s and
accelerating ever since, the human consumption
of fossil fuels has elevated carbon dioxide levels
from a concentration of
), which
is the main ingredient for cement (CaSiO
3
) pro-
duction. The reaction steps in this manufacture
are given as follows:
quicklime
CaCO
3
!
CaO
þ
CO
2
D
CaO
þ
SiO
2
!
CaSiO
3
rst step has
considerable contribution to global warming.
While fossil fuel combustion and deforestation
each produce signi
Carbon dioxide produced in the
280 ppm to more than
380 ppm today (an increase of 35.7 %). These
increases are projected to reach more than
560 ppm (an increase of 100 %) before the end of
the twenty-
*
cantly more carbon dioxide
in the Earth
s atmosphere, cement production
alone is responsible for approximately 2.5 % of
total worldwide
'
emissions
from industrial
rst century. It is known that carbon
