UNIVERSITY OF DAR ES SALAAM
DAR ES SALAAM UNIVERSITY COLLEGE OF EDUCATION (DUCE)
FACULY OF SCIENCE
DEPARTMENT: CHEMISTRY
COURSE NAME: ANALYTICAL AND ENVIRONMENTAL CHEMISTRY
COURSE CODE: CH 262
COURSE INSTRUCTOR: Dr DATIVA SHILLA
TYPE OF WORK: GROUP REPORT
DATE OF SUBMISSION: 25TH JUNE, 2024
GROUP NO: 05
PARTICIPANTS.
S/N STUDENT NAMES
1
GONELIMALI, ROLAND J
2
MLELWA, MARIAM V.
3
KILELA RAMADHAN
4
WILLIAM, JACKLINE J
5
MSAFIRI WITSON
6
KASHENSHE THEONESTINA
7
NAMOYO, BAHATI ZAKAYO
8
MGIMBA, DANIEL S.
9
MOHAMEDI, SHAMZI SAIDI
REGISTRATION NO.
2022-04-02147
2022-04-07818
2022-04-04231
2022-04-13316
2022-04-08409
2022-04-03778
2022-04-09880
2022-04-07304
2022-04-08097
COURSE
BSE
BSE
BSE
BSE
BSE
BSE
BSE
BSE
BSE
SIGNATURE
QUESTION.
Discuss the phenomena of greenhouse effect and enhanced greenhouse effect in relation to
global warming and climate change.
THE NATURAL GREENHOUSE EFFECT
Is natural process that occurs when gases in the Earth's atmosphere trap heat from the sun, making
the planet warmer than it would be without an atmosphere (Thakhur, 2011).
The main source of heat to the Earth is solar energy, which is transmitted from the Sun to the Earth
by radiation and is converted to heat at the Earth’s surface. To balance this input of solar radiation,
the Earth itself emits radiation to space. Some of this terrestrial radiation is trapped by greenhouse
gases and radiated back to the Earth, resulting in the warming of the surface known as the
greenhouse effect which makes the earth habitable. On average, 343 W/m2 of sunlight fall on
earth, roughly 1/3 of which is reflected back into space. The other 2/3 reaches the ground, which
reradiates it as longer wavelength, infrared radiation, warming the atmosphere (Thakhur, 2011).
Sunlight enters the Earth's atmosphere, passing through the greenhouse gases. Greenhouse gases
include Water vapor, Carbon dioxide (CO2), Methane (CH4), Nitrous oxide (N2O), Tropospheric
ozone (O3) and Chlorofluorocarbons (CFCs).
Natural greenhouse effect
ENHANCED GREENHOUSE EFFECT
This results from an increase in the atmospheric concentrations of the greenhouse gases, thus
causes more heat to get trapped, which makes the Earth warmer. Anthropogenic increase in
greenhouse gases has been inducing rapid surface warming of the Earth. The naturally occurring
greenhouse gases such as CO2, CH4, and N2O show large increases over the past century due to
human activity. Mankind’s activities, particularly those associated with industrialization, largescale land clearance and chemically improved agriculture, are adding increasingly large amounts
of these radiatively active gases to the atmosphere (M.D.H. Jones and A. Henderson-Seller).
Each greenhouse gas has a its own Global Warming Potential, that is, the capacity to cause
global warming which depends on its radiative efficiency, molecular weight and lifetime in
atmosphere. CO2 has longest lifespan of 50-200 years (IPCC GWP Values, 1995).
Human activities increasing Greenhouse Gases
1. Burning fossil fuels
The hydrocarbons in coal, petroleum and natural gas emit much of the carbon dioxide in the
atmosphere. Coal is the fossil fuel with the greatest carbon content, thus emits more Carbon
dioxide when burned, followed by petroleum and natural gas that has the lowest carbon content.
Carbon dioxide primarily emitted by burning fossil fuels accounts for about 75% of current global
warming. Cement manufacture is a smaller but significant source of Carbon dioxide emission
(Marquita K. Hill, 2020).
2. Production, distribution and use of energy
Methane escapes during coal mining and from natural gas from oil wells, also can escape from
wells, pipelines, and other infrastructure
3. Waste management
Decomposition of organic matter in landfills contributes to methane emission. Solid waste
combustion facilities release nitrous oxide.
4. Burning forests
Mostly in tropical deforestation, when felled trees are burned and their stored carbon released as
carbon dioxide to the atmosphere.
ENHANCED GREEN HOUSE EFFECT & GLOBAL WARMING
Enhanced greenhouse effect is closely linked to global warming. The increase in concentration of
greenhouse gases in the atmosphere results to more trapping of heat from the sun and hence more
warming of the earth’s surface.
Global warming: Is the long-term increase of the Earth’s surface temperatures caused by the
increasing concentration of greenhouse gases in the atmosphere. This is caused by the increased
concentration of greenhouse gases in the atmosphere. Greenhouse gases e.g. carbon dioxide (CO2),
methane and nitrous oxides, act like a blanket and trap heat inside the Earth's atmosphere.
As concentrations of these gases build up, they become more effective at preventing heat being
lost into space. The amount of heat being lost from the atmosphere is less than the energy entering
the atmosphere. As a result the temperature of the atmosphere increases.
GLOBAL WARMING & CLIMATIC CHANGE
The rise in temperatures in Earth’s atmosphere leads to changes in global climate patterns. This is
because the changes currently observed and predicted are not limited to temperature alone but also
involve changes in climate patterns and related events like sea rise, floods, droughts and landslips.
Climate change: Refers to long-term changes in temperature and weather patterns. Climate
change includes major changes in temperature, precipitation, or wind patterns, among other
effects, that occur over several decades or longer.
Global warming and climatic changes results to rise of sea level by expanding ocean water,
melting mountain glaciers and ice caps, and causing portions of the Greenland and Antarctic ice
sheets to melt or flow into the ocean. Such rise would flood coastal cities, force people to abandon
low-lying islands, and completely inundate coastal wetlands. Also results to drought, changes in
distribution of rainfall and loss of biodiversity.
A summary of how human activities leading to global warming and climate change.
CONCLUSION
Generally, climate change is a global problem that is hard to solve by single countries. Therefore
in 1998, the Kyoto Protocol was negotiated in Kyoto, Japan where it requires participating
countries to reduce their anthropogenic greenhouse gas emissions (CO2, CH4, N2O, HFCs, PFCs,
and SF6) by at least 5% below 1990 levels in the commitment period 2008 to 2012. The Kyoto
Protocol was eventually signed in Bonn in 2001 by 186 countries. However, all countries should
take measures and management procedure such as the use of alternative energy sources, removal
of pollutants from the products of combustion, improvement in the efficiency of the combustion
process itself, and energy conservation. Also several different approaches should be used to reduce
pollutants in industrial exhausts, including electrostatic precipitation, filtration, and scrubbing.
REFERENCES
B. Bolin (1986). The Greenhouse Effect, Climatic Change and Ecosystems. New York
Dejene A. Tessema (2008) Environmental Chemistry, Nairobi, Kenya African Virtual University)
Publisher: African Virtual University, Nairobi, Kenya
IPCC. (1995). Climate Change 1995: The Science of Climate Change. Edited by J.T. Houghton,
L.G. Meira Filho, B.A. Callander, N. Harris, A. Kattenberg, and K. Maskell.
R. S. J. Tol and P. Vellinga .Climate Change, the Enhanced Greenhouse Effect and the Influence
of the Sun: A Statistical Analysis
Thakhur, I.S (2011). Environmental Biotechnology; Concepts and applications 2nd Ed. New Delhi.
I.K I international Publishing House Pvt. Ltd