CSEC Geography - Global warming

This document gives a background and definition of the key terms re global warming, includes greenhouse gases, greenhouse effect.

1. 5
th
Form Geography
Global Warming
Prepared by: O. Johnson

Global warming: the increase in the average temperature of the earth’s atmosphere and oceans.
The Greenhouse Gases
There are gases that exists naturally in the earth’s atmosphere. The primary greenhouse gases in
the earth’s atmosphere are: water vapour, carbon dioxide, methane, nitrous oxide.
Greenhouse Gases Chemical Formula
Carbon Dioxide C02
Water Vapor H20
Nitrogen Oxide N20
Methane CH4

Greenhouse Gases- These are gases that trap heat within the earth’s atmosphere e.g.
Carbon Dioxide, Methane, Nitrous Oxide, Water Vapour.
Greenhouse Effect
What happens?
 Incoming short-wave radiation (visible light) from the sun passes largely uninterrupted
through the atmosphere to reach the earth.
 This energy heats up the earth’s surface, which in turn gives off heat in the form or long
wave radiation
 Some of this heat from the earth escapes to space but some is trapped and absorbed by
greenhouse gases in the atmosphere
 This warms the atmosphere creating a kind of insulating blanket around the earth. This is
the greenhouse effect. Without it, the temperature would be too cold and life would not
exist on earth. They allow short-wave radiation to pass through the atmosphere but trap a

2. portion of outgoing long-wave radiation. They reflect the heat back in the same way as a
greenhouse- letting heat in but preventing it from escaping.
Greenhouse effect- the trapping of heat within the earth’s atmosphere.
Greenhouse gases: the gases that trap heat within the Earth’s atmosphere such as carbon
dioxide, methane and water vapour
Global warming: the increase in the average temperature of the earth’s atmosphere and oceans.
Causes of global warming
Sources of Carbon Dioxide
Burning of Fossil Fuels:
The three main fossil fuels are oil, coal and natural gas. They are used for energy production.
Several countries use fossil fuels to generate their electricity. For example Jamaica uses oil to
generate its electricity. Several other sectors including the transportation and industry uses fossil
fuels for energy production. When these fossil fuels are burnt they release carbon dioxide in the
atmosphere contributing to global warming.
Deforestation
Deforestation is the cutting down of trees. There are several reasons for deforestation. These
include: tourism development, agriculture, logging, infrastructural development (roads) and
mining. Trees are a part of the carbon cycle, they absorb and store huge amounts of carbon
dioxide. When deforestation takes place this stored carbon dioxide will be released into the
atmosphere contributing to global warming.
Transportation
The transportation industry also produces carbon dioxide. Buses, cars, trucks, ships, trains and
planes use petroleum based fuels (gasoline and diesel) as their energy source. When these
different modes of transportation burn gasoline or diesel carbon dioxide is emitted thus
contributing to global warming.

3. Manufacturing Industry
Manufacturing industries cannot operate without an energy source. These industries are energy
intensive and fossil fuels are burnt to provide this energy. Once fossil fuels are burnt carbon
dioxide is released.
Sources of Methane
Burning of fossil fuels
The burning of fossil fuels not only produces carbon dioxide but methane is a by-product as well.
Leaks from natural gas line
Methane is the main component of natural gas. Methane is emitted in the atmosphere during the
production, processing and distribution of natural gas to the atmosphere during the production. If
there are leakages methane will escape into the atmosphere as well.
Livestock Farming
An important source of methane emission is from enteric fermentation in farm animals. Animals
like cows, sheep and goats are examples of ruminant animals and during their normal digestion
process they create large amounts of methane.
Enteric fermentation occurs because of microorganisms in the stomach of these animals, which
creates methane as a by-product that is either exhaled by the animal or released via flatus. Most
of the methane are belched by the animal but a small percentage is also produce in the large
intestine and passed out as flatulence. Large scale cattle farming produces a lot of methane.
Because humans raise these animals for food, the emissions are considered to be human
related.
Landfills
Landfills and open garbage dumps are full of organic matter from our garbage (food scraps cut
grass and leaves). Every time new garbage comes in it is pilled over the old garbage that was
already there. The organic matter in our garbage gets trapped in anaerobic conditions where
there is no oxygen. This provides excellent conditions for methane producing microbes to break
down the waste, which produces large amounts of methane emissions.

4. Sources of Nitrous Oxide
Agriculture
Nitrous oxide is emitted when people add nitrogen to the soil through the use of synthetic
fertilizers
Car Exhausts
Most vehicles use fossil fuel based sources for energy. Carbon dioxide is not the only gas that is
emitted from fossil fuel combustion. Nitrous oxide is release as well and this comes from all
modes of transportation ( trucks, trains, planes, cars etc)
Consequences of Global Warming
Sea level rise
As the average temperature of the Earth rises polar ice in the Arctic and Antarctic melts. Glaciers
and ice sheets in places such as Greenland, North America and Europe are also melting. This
water ends up in our oceans causing a rise in sea level. Sea level has risen 8 inches since
1870. During this century, sea level is expected to rise at an even faster rate. Some experts
predict a rise in sea level of over a meter by 2100. As sea level rises, low lying areas near the
coast are threatened.
Beach erosion
There are subsequent effects of sea level rise and beach erosion is one of them. With the rising of
sea level beaches are being affected. As the sea is encroaches unto the land beaches are being
removed. Hellshire beach in Portmore is experiencing this problem. Countries especially in the
Caribbean that are dependent on tourism will be affected as the white sand beaches are one of the
main attractions.
Flooding of low lying islands
Coastal flooding is another effect of sea level rise. There are some islands around the world that
there highest elevations are a few metres above sea level. These include some islands in the
pacific such as: Kiribati, Vanuatu, Cooks Islands, Tuvalu and others. Scientists believed that in

5. the future some of these islands will be submerged. Cayman Islands, the Bahamas, Turks and
Caicos in the Caribbean are also at risk from flooding from this sea level rise.
In addition approximately 40% of the world’s population lives within 100km of the coast. Rising
sea level will also cause flooding of property and farm lands on low lying areas near the coast.
Contamination of Underground Water (Saline Intrusion)
Saline intrusion occurs when sea water encroaches unto the land and infiltrate into underground
water sources e.g. aquifers. Sea water has a high salt content and if it enters fresh water sources it
will contaminate it. Some ground water sources in Jamaica and Barbados are already affected.
Coral Bleaching
Corals cannot survive if the water temperature is too high. If the temperature is too high a
situation knows as coral bleaching will occur. Coral Bleaching occurs when coral polyps lose the
zooxanthelae (the algae that provides much of its energy). The algae is also responsible for the
corals colour, when coral bleaching occurs the coral will appear white.
The warming of tropical seas can cause harmful bleaching of corals which are important for
tourism and fishing. In the last decade, more than 300km of Belize’s Barrier reef has been
bleached.
More Intense Hurricanes
Hurricanes gain their energy from warm seas. They form only when the sea surface temperatures
are above 27
0
C. Warmer seas might lead to a longer storm season, with more frequent and more
powerful hurricanes.
Changing rainfall patterns: Experts believe that rainfall patterns may change significantly.
Some areas, such as the subtropics, may receive less rainfall and experience more frequent
droughts. Other areas, such as the higher latitudes, may receive more rainfall. In some areas it is
expected that heavy rainfall will be more frequent, increasing the likelihood of floods.
Species Extinction
Some organisms may find it difficult to adapt to the changing climate and may become extinct.
Polar bears, for example, are having difficulties coping with the effects of rising temperatures in

6. the arctic Polar bears in the Arctic maybe threatened by the melting of floating ice that they need
for hunting and survival.
More frequent extreme weather events: In the past forty years or so, extreme weather events
such as droughts and heat waves have been occurring more frequently. Global warming is
believed to be responsible for this. Scientists predict that extreme weather events will become
more frequent and more intense as the Earth warms up. Heat waves caused by global warming
present greater risk of heat-related illness and death, most frequently among people who have
diabetes who are elderly or are very young

Impacts of global warming on the Caribbean and the UK
The Caribbean
 Rising sea levels will flood low-lying islands and countries, ruin beaches and threaten
hotels and the tourist industry. The Caribbean countries are entirely dependent on
tourism. The white sand beaches are used as attractions for tourist. However, due to
rising sea levels the beaches are receding. Environmentalists believes that the sand at the
seven mile beach in Westmoreland is receding by more than a metre annually and there
is a possibility that the beach could be totally lost within 30 years. According to the
World Bank, some areas of the island of St. Vincent have lost up to 30 metres of
beach over the last nine years. The beach in Hellshire is also experiencing
significant erosion. The continued disappearance of Hellshire Beach would mean
significant losses of livelihood for the fisherfolk and others who derive their income there
 The warming of the Caribbean Sea is causing ‘bleaching’ of coral reefs which are
important for tourism and fishing. In the last decade, more than 300km of Belize’s
barrier reef has been bleached and could die. A further temperature rise of 1
degrees Celsius could bleach 80% of coral reefs worldwide.
 As oceans get warmer, tropical storms could become more violent and hurricanes
could produce more powerful winds. Costly damage to buildings and roads could
become worse in the more frequent storms.
UK

7.  By 2014 the United Kingdom's seven warmest and 4 out of its 5 wettest years had
occurred between the years of 2000–2014. Higher temperatures increase evaporation and
consequently rainfall. In 2014 England recorded its wettest winter in over 250 years with
widespread flooding. In winter 2014, flood water inundated parts of the region:
swamping properties, running crops and endangering life.
 2018's temperature was 16.1 °C (61.0 °F), meaning it ranks as the 18th warmest June
recorded in England in the past 359 years, also being the warmest since 1976.
 Rising sea level is causing erosion on the coastline and people are losing their homes to
the sea. Erosion, cause by waves attacking the cliffs, has claimed as many as 35 houses in
the past decade
 Due to increasing temperatures and heat waves there are more incidences of forest
fires. A heat wave in 2018 caused a forest fire in Saddleworth that burnt for days-
damaging nature, threating local towns and increasing air pollution. More global
warming and more intense heat waves could lead to wildfires becoming a regular
threat.
 Many seabirds are struggling to find food because of the effects of global warming
on their prey. In little under 20 years, the puffin population has plummeted from
33,000 to just 570
Measures to reduce global warming in the Caribbean and the UK
Caribbean
Some countries in the Caribbean are looking towards developing renewable energy and
be less dependent on fossil fuels. These measures will reduce the emission of greenhouse
gases.
 Jamaica’s first wind energy project, the Wigton wind farm: with 23 turbines and support
from the Netherlands government, the project is already meeting Jamaica’s renewable
energy targets
 The promotion of solar water heaters in Barbados using heat from the sun: 32 000 solar
heaters have already been installed in homes, businesses and hotels, saving around US$
6.5 million in fuel that would otherwise have been imported.

8.  St Lucia, Dominica and Grenada are all trying to become the world’s first non-carbon
fuel-based economies- using wind, wave and solar power instead of coal, oil and diesel to
provide all their energy needs.
 Barbados is looking at using offshore wind farms, based at sea, to generate electricity.
UK
Environmental, or green, issues are becoming increasingly important, especially in developed
countries. As people become aware of the damage being done to the environment through
industry and motor vehicles, politicians and governments are taking more and more steps to try
and stop climate change.
In the UK, for example, all major political parties, and a majority of the population, say they are
concerned about global warming, so action is being taken by the government and individuals to
try to cut down on emissions of greenhouse gases.
Action to cut greenhouse gases
The UK has said it wants to cut its emissions of carbon dioxide by 20% before 2010 and 50%
before 2050. These targets are very ambitious and it requires positive action to achieve them:
 An increase in renewable energy which, unlike fossil fuels, releases no greenhouse gases.
Sources of renewable energy in the UK include wind power tidal power which uses ocean
waves, and hydro-electric power using the power of water as it flows downhill. Nuclear is
considered by many to be an environmentally friendly source of energy but others are
concerned about its potential dangers
 Taxes placed on the most polluting types of motor vehicles. People are being encouraged
to buy cars with equipment that stops pollutant escaping, to use more environmentally
friendly fuel such as autogas and to buy cars with greater fuel efficiency that go further
on less petrol
 Grants given to home owners to make their homes more carbon neutral (which means no
carbon dioxide is released into the atmosphere). Grants are available to install solar
power to heat and light homes and to put in insulation that stops heat being lost, saving
electricity on heating homes
 Plans to tax airline flights-one of the most polluting forms of travel

9. Individuals are also being encouraged to take action to combat climate change by:
 Installing energy-efficient equipment, such as light bulbs and heating systems, in their
homes
 Cutting down on their electricity use by turning off televisions, computers, radios and
other electrical goods when they are not being used.
 Taking public transport instead of driving their own cars and when they have to drive,
doing so more slowly to use less petrol
 Cutting down on garbage and recycling more. In the UK garbage is mainly burnt or
buried and both these methods release harmful gases. Local governments are now giving
people more than one waste bin so that they can spate their garbage into normal waste,
cardboard, and plastics that can be recycled