4. • Climate change is the change in our weather patterns that are occurring
because of an increase in the earth's average temperature.
• It is also known as global warming.
• Climate change may result from both natural and human causes though
the human causes appear to be increasingly responsible for climate
change over the past few decades
5. • Climate change is one of the most formidable developmental challenges faced by
humanity today.
• Its consequences are global and intergenerational.
• The global climate is now changing faster than at any point of time in human
civilisation.
• Climate change will affect, in profoundly adverse way, some of the most
fundamental determinants of health: food, air and water, adequate shelter and
freedom from disease.
6. • The Earth's climate, although relatively stable for the past 10,000 years or so, has
always been changing, mainly due to natural causes such as volcanic activity.
• But since the 1900s more rapid changes have taken place and these are thought to
be mainly man-made
• Global warming mean temperatures increased by 0.74° C during last 100 years and
by the year 2 100 best estimates predict between a 1.8° C and 4° C rise in average
global temperature. Although it could possibly be as high as 6.4°C
9. Natural Causes
• The causes of climate change is divided into natural causes and
anthropogenic causes (Man-made).
• Natural causes:
These have been caused by many natural factors, including changes in the sun,
emissions from volcanoes, variations in Earth’s orbit and levels of
carbon dioxide (CO2).
• Anthropogenic causes:
Burning of fossil fuels, cutting down forests and farming livestock are increasingly
influencing the climate and the earth's temperature.
10. Strength of the sun:
Sun-Almost all of the energy that affects the climate on Earth originates
from the Sun.
Only some of the solar energy intercepted at the top of the atmosphere
passes through to the Earth, some of it is reflected back into space and
some is absorbed by the atmosphere.
The energy output of the Sun is not constant, it varies over time and this has an
impact on our climate.
11. Changes in earth’s orbit, axial tilt and precession:
The three changes in the Earth’s orbit around the Sun — eccentricity, axial tilt, and
precession are collectively called ‘Milankovitch cycles’.
According to Milankovitch’s theory, these three cycles combine to affect the
amount of solar heat that reaches the Earth’s surface.
The time period between these changes can be tens of thousands of years
12. Milankovitch’s three cycles:
The Earth’s orbit:
• The Earth’s orbit around the Sun is an ellipse but it isn’t always the same shape of
ellipse. Sometimes, it is almost circular.
• The Earth moves closer and further away from the Sun in its orbit.
• When the Earth is closer to the Sun, our climate is warmer and this cycle also
affects the length of the seasons
13. Circular orbit(left) and Elliptical orbit(right). When the earth is closer to the
Sun, its climate is warmer
14. The Earth’s axial tilt:
• The tilt in the axis of the Earth is called its ‘obliquity’.
• This angle changes with time, and over about 41 000 years it moves from 22.1° to
24.5° and back again.
• When the angle increases, the
summers become warmer and
the winters become colder.
15. The Earth’s precession:
• The Earth wobbles on its axis, much like a spinning top that is slowing down. This is
called ‘precession’ and is caused by the gravitational pull of the Moon and the Sun
upon the Earth.
• Which make changes on North pole where it points to in the sky, but over
thousands of years the axis moves around in a circle and points at different parts of
the sky.
• It impacts on the seasonal contrasts between hemispheres and the timing of the
seasons
17. Greenhouse Gases:
Greenhouse gases include carbon dioxide (CO2), methane (CH4) and water vapour
(H2O).
H2O stays in the atmosphere for just a few days, it is the most abundant
greenhouse gas in the atmosphere
CH4 stays in the atmosphere for about nine years until it is removed by oxidation
into CO2 and water.
CO2 stays in the atmosphere much longer, from years to centuries, contributing to
longer periods of warming.
These gases trap solar radiation in the Earth’s atmosphere, making the climate
warmer.
18. Changes in Ocean currents:
Ocean currents carry heat around the Earth.
As the oceans absorb more heat from the atmosphere, sea surface temperature
increases and the ocean circulation patterns that transport warm and cold water
around the globe change.
The direction of these currents can shift so that different areas become warmer or
cooler.
As oceans store a large amount of heat, even small changes in ocean currents can
have a large effect on global climate.
20. Volcanic Eruption:
Volcanoes affect the climate through the gases and particles thrown into the
atmosphere.
The effect of volcanic gases and dust may warm or cool the Earth’s surface,
depending on how sunlight interacts with the volcanic material.
During major explosive volcanic eruptions, large amounts of volcanic gas, aerosol
droplets and ash are released.
In the present day, the contribution of volcanic emissions of CO2 into the
atmosphere is very small; equivalent to about one per cent of anthropogenic
(caused by humans) emissions.
21. Changes in land cover:
On a global scale, patterns of vegetation and climate are closely correlated.
Vegetation absorbs CO2 and this can buffer some of the effects of global warming.
On the other hand, desertification amplifies global warming through the release of
CO2 because of the decrease in vegetation cover
23. Man made/Anthropogenic:
Anthropogenic means ‘changes in environment caused by people’. Those changes
which are the result of human activities are known as anthropogenic changes.
Types of anthropologenic causes of climate changes are:
1. Industrial processes
2. Air pollution
3. Deforestation
4. Mining
24. 1.INDUSTRIAL PROCESSES:
Manufacturing and industry produce emissions from burning fossil fuels to
produce energy for making many things like cements,iron, steel, plastics and other
goods.
The burning of fossil fuels by industries and automobiles have increased the
amount of carbon dioxide in the atmosphere by more than 20% over the past 100
years
In 2021 the percentage of global emissions come from industry is around 23%
These adds huge quantities of greenhouse gases to those present in the
atmosphere increasing greenhouse effect and global warming which sums up to
become changes in global climate
26. 2.AIR POLLUTION :
Air pollution is caused by fertiliser use, livestock production, and certain industrial
processes that release fluorinated gases.
Pollutants in the air can produce serious environmental issues and contribute to
climate change.
The major concerns include:
i. The ability of pollutants to trap too much heat in the atmosphere.
ii. The mixture of gases with moisture in the atmosphere which produces damaging
acid rain.
iii. The increase in unnatural ozone levels.
iv. The presence of particles in the atmosphere that block sunlight.
28. 3.DEFORESTATION :
Deforestation is the permanent removal of trees to make room for something
besides forest.
This can include clearing the land for agriculture or grazing, or using the timber for
fuel, construction or manufacturing.
The trees absorb Carbin dioxide and release Oxygen in the air. But, due to
deforestation the content of Carbondioxide has increased in the atmosphere,
leading to warm air or rise in temperature leading to global climate changes.
30. 4.MINING:
Coal mining releases methane, a potent greenhouse gas.
Methane emissions from coalmines has a global warming potential 21 times
greater than that of carbon dioxide over a 100-year timeline
Mining activities thus causes affect weather patterns and climate stability which
can affect future water supplies and is responsible for global warming
33. Effects of Climate change
• Warmer temperatures over time are changing weather patterns and
disrupting the usual balance of nature, posing many risks to human
beings and all other forms of life on Earth.
• Because the Earth is a system, where everything is connected, changes
in one area often influence changes in all others. The consequences of
climate change now include:
• intense droughts
• water scarcity
• severe fires
• rising sea levels
• flooding
• Loss of species
34. Effects of Climate change
• Climate change disrupts weather patterns and causes extreme weather events
become more common. These include hurricane activity, droughts and floods.
35. Effects of Climate change
a) Drought b) Flood c) Wild fire
• Droughts can stir destructive
sand and dust storms
• Deserts are expanding,
reducing land for growing food
• Many people now face the
threat of not having enough
water on a regular basis
• Climate change results in more
intense rainfall
• . This increases the chances of
flooding
• Parched soils increase the risk
of flash flooding when it rains.
• Climate change promotes the
type of weather that makes
wildfires
• Climate change increases
evaporation. This can cause
vegetation to dry out
• When a fire starts in an area
with very dry vegetation, it can
spread rapidly.
36. Rising sea level
• Rising temperatures are causing
sea levels to increase.
• The rising water can cover coastal
areas, destroying habitats and
displacing whole populations
from low-lying areas.
• Global average sea level has risen
8–9 inches (21–24 centimeters)
since 1880
• In 2021, global sea level set a
new record high—97 mm (3.8
inches) above 1993 levels.
Rising sea levels are driven by two main processes:
1. Ice Melt: When the atmosphere and ocean get warmer, ice sheets and
glaciers melt, resulting in the addition of fresh water to the ocean.
2. Thermal Expansion: As ocean water gets warmer, it expands, causing
sea levels to rise.
38. Loss of Biodiversity
0
20
40
60
80
100
70 %
Percentage
Coral
Loss
Coral Bleaching
Temperature Rise (°C)
1.5
Species Loss
insects plants vertebrates
0
5
10
15
20
6
8
4
2°C
Percentage
Species
Loss
1.5°C
From the given data if the global temperature rises
for just 1.5 C almost 70% of the coral reef will be
lost.
And from this data we can understand how climate change
affects the species population.. if the temperature rises for
just 1.5 C.. 6% of insect , 8% of plant and 4% of vertebrates will
be lost
. A stable climate supports this process and allows
living things to thrive. If the climate changes
quickly, organisms don’t have enough time to
adapt to new conditions and may no longer be
able to survive.
The increase in global temperatures is causing a
reduction in sea ice. This causes problems for animals
that depend on the ice to hunt, mate and sleep.
40. Preventive Measures of Climate change
• Change a light: Replacing one
regular light bulb with a compact
fluorescent light bulb will save 150
pounds of carbon dioxide a year.
41. • Switch to sustainable transport:
• Petrol and diesel vehicles, planes and ships use fossil fuels
• Reducing car use, switching to electric vehicles and minimising plane travel will
help in stopping climate change and also help in reducing air pollution.
42. • Use Renewable Energy Sources:
• It’s no secret that extracting fossil fuels is wrecking our planet, which is why we need to shift
to renewable energy sources.
• there are plenty of ways you can reduce your energy consumption, including finding a green
energy provider, or replacing your burned-out fluorescent lightbulbs with LEDs
43. • Protect the oceans:
• Oceans and seas are the largest storage of greenhouse gases and are an
exceptional support system for life on this planet. Limiting overfishing,
unsustainable development activities in coastal areas and the consumption of
environmentally friendly products is now essential.
44. • Restore nature to absorb more carbon:
• The natural world is very good at cleaning up our emissions, but we need to look after it.
Planting trees in the right places or giving land back to nature through ‘rewilding’ schemes is
a good place to start. This is because photosynthesising plants draw down carbon dioxide as
they grow, locking it away in soils
45. • Raising awareness:
• Raising awareness and thereby understanding of the effects of climate change on health will
facilitate both behavioural change and societal support for the actions needed to reduce
greenhouse gas emissions. It can also help in getting health-care professionals to support
strategies for mitigation and adaptation that will both improve health and reduce
vulnerability.
47. Conclusion
In conclusion, climate change is the most significant
problem facing the world. Global warming is increasing
day by day. If we cannot prevent it as soon as possible,
our world will face undesirable consequences. Artificial
intelligence and machine learning, which have been
quite advanced recently, is our immense weapon in the
fight against climate change. Recently, studies have been
carried out to tackle climatechange with these subjects.
Governments, nonprofit organisations, and companies
also have the responsibility to implement and contribute
to these studies.
