CLIMATE CHANGE

 Climate is the average weather at a given point and time of year, over a long period
(typically 30 years).

 We expect the weather to change a lot from day to day, but we expect the climate to
remain relatively constant.

 If the climate doesn’t remain constant, we call it climate change.

The key question is what is a significant change – and this depends upon the underlying level of
climate variability

Global warming
Global warming –is a phenomenon of climate change
characterized by a general increase in average
temperatures of the Earth, which modifies the weather
balances and ecosystems for a long time. It is directly
linked to the increase of greenhouse gases in our
atmosphere, worsening the green house effect.

Evidence of Climate Change

0.6oC
warmin
g past
century

Causes Of Climate Change

Natural causes
 Volcanic Eruptions

 Ocean current

 Earth orbital changes

 Solar Variation

 Forest fire
Volcanic Eruptions
 When a volcano erupts it throws out large
volumes of sulphur dioxide (SO2), water
vapour, dust, and ash into the atmosphere.

Ocean current
 The oceans are a major components of climate system.
Ocean currents move vast amounts of heat across the
planet.

Earth orbital changes

 The earth makes one full orbit around the sun each
year. It is tilted at an angle of 23.5° to the
perpendicular plane of its orbital path. Changes in
the tilt of the earth can lead to small but
climatically important changes in the strength of
the seasons.

Fire forest
 A wildfire is any uncontrolled fire in a area of
combustible vegetation that occurs in the
countryside or a a wilderness area.

Artificial factors
 Human Activities

 Emission of Greenhouse gases

 Solar Radiation
Human activities
 There is strong evidence that the climate change over the last half-century has been
caused largely by human activity, such as the burning of fossil fuels, including
agriculture, deforestation, Coal mining and etc.

HUMAN CAUSES

 Deforestation

 Mining

 Fossil fuels

 Waste Disposal

 Overconsumption

 Industrial processes

 Intensive Farming

Deforestation
The exploitation of forests has a major role in climate change. Trees help regulate the climate
by absorbing CO2 from the atmosphere. When they are cut down, this positive effect is lost and
the carbon stored in the trees is released into the atmosphere

Intensive farming
Another cause of global warming is intensive farming, not only with the ever-increasing
livestock, but also with plant protection products and fertilizers. In fact, cattle and sheep
produce large amounts of methane when digesting their food, while fertilizers produce nitrous
oxide emissions.

Waste disposal
Waste management methods like landfills and incineration emit greenhouse and toxic gases -
including methane - that are released into the atmosphere, soil and waterways, contributing to
the increase of the greenhouse effect.

Fossil fuel
The massive use of fossil fuels is obviously the first source of global warming, as burning coal,
oil and gas produces carbon dioxide - the most important greenhouse gas in the atmosphere - as
well as nitrous oxide.

Mining
Modern life is highly dependent on the mining and metallurgical industry. Metals and minerals
are the raw materials used in the construction, transportation and manufacturing of goods. From
extraction to delivery, this market accounts for 5% of all greenhouse gas emissions.

Overconsumption
Finally, overconsumption also plays a major role in climate change. In fact, it is responsible for
the overexploitation of natural resources and emissions from international freight transport,
which both contributes to global warming.

Green House Gases

Emission of green house gases such as. . .

 Water vapour

 Carbon dioxide

 Methane

 Nitrous oxide

Greenhouse gases
Effect of greenhouse gases
 Greenhouse gases trap the infrared heat that is
trying to escape back into space.

 The atmospheric trapping or reflection of

radiant energy back toward the earth.

 Increase in the global average surface

temperature.

 Greenhouse effect, contributing to global

warming.

Solar radiation
 51% of solar radiation absorb by earth. 20%
scattered by the clouds 19% absorb by clouds
and atmosphere and 6% scattered by
atmosphere, 4% reflected by surface.

EFFECTS OF CLIMATE CHANGE

 Climate change destabilizes the Earth’s temperature equilibrium and has far-reaching
effects on human beings and the environment. During the course of global warming, the
 energy balance and thus the temperature of the earth change, due to the increased
concentration of greenhouse gases, which has a significant impact on humans and the
environment.

The direct consequences of man-made climate change include:

 rising maximum temperatures

 rising minimum temperatures 

 rising sea levels 

 higher ocean temperatures 

 an increase in heavy precipitation (heavy rain and hail)

 shrinking glaciers

 thawing permafrost

The indirect consequences of climate change, which directly

affect us humans and our environment, include: 
 an increase in hunger and water crises, especially in developing countries

 health risks through rising air temperatures and heat waves 

 economic implications of dealing with secondary damage related to climate change 

 increasing spread of pests and pathogens

 loss of biodiversity due to limited adaptability and adaptability speed of flora and fauna  

 ocean acidification due to increased HCO3 concentrations in the water as a consequence

of increased CO₂ concentrations

 the need for adaptation in all areas (e.g. agriculture, forestry, energy, infrastructure,
tourism, etc.)

Observation In Climate Change

 The Earth's climate has changed throughout history. Just in the last 650,000 years there
have been seven cycles of glacial advance and retreat, with the abrupt end of the last ice
age about 7,000 years ago marking the beginning of the modern climate era — and of
human civilization. Most of these climate changes are attributed to very small variations
in Earth’s orbit that change the amount of solar energy our planet receives . The current
warming trend is of particular significance because most of it is extremely likely (greater
than 95 percent probability) to be the result of human activity since the mid-20th century
and proceeding at a rate that is unprecedented over decades to millennia. 

Earth-orbiting satellites and other technological advances have enabled scientists to see
the big picture, collecting many different types of information about our planet and its
climate on a global scale. This body of data, collected over many years, reveals the
signals of a changing climate. 

The heat-trapping nature of carbon dioxide and other gases was demonstrated in the mid-
19th century.2 Their ability to affect the transfer of infrared energy through the
atmosphere is the scientific basis of many instruments flown by NASA. There is no
question that increased levels of greenhouse gases must cause the Earth to warm in
response. 

Ice cores drawn from Greenland, Antarctica, and tropical mountain glaciers show that the
Earth’s climate responds to changes in greenhouse gas levels. Ancient evidence can also
be found in tree rings, ocean sediments, coral reefs, and layers of sedimentary rocks. This
ancient, or pale climate, evidence reveals that current warming is occurring roughly ten
times faster than the average rate of ice-age-recovery warming.

Global Climate in 2015-2019: Climate change accelerate

The tell-tale signs and impacts of climate change – such as sea level rise, ice loss and
extreme weather – increased during 2015-2019, which is set to be the warmest five-year
period on record,

According to the World Meteorological Organization (WMO). Greenhouse gas

concentrations in the atmosphere have also increased to record levels, locking in the
warming trend for generations to come.
 The WMO report on The Global Climate in 2015-2019 -- released to inform the United
Nations Secretary-General’s Climate Action Summit, says that the global average
temperature has increased by 1.1°C since the pre-industrial period, and by 0.2°C
compared to 2011-2015.

The climate statement – which covers until July 2019 - was released as part of a high-
level synthesis report from leading scientific institutions United in Science under the
umbrella of the Science Advisory Group of the UN Climate Summit 2019. The report
provides a unified assessment of the state of Earth system under the increasing influence
of climate change, the response of humanity this far and projected changes of global
climate in the future. It highlights the urgency and the potential of ambitious climate
action in order to limit potentially irreversible impacts.

“Climate change causes and impacts are increasing rather than slowing down,” said
WMO Secretary-General Petteri Taalas

Sea level rise: 

Over the five-year period May 2014 -2019, the rate of global mean sea-level rise has
amounted to 5 mm per year, compared with 4 mm per year in the 2007-2016 ten-year
period. This is substantially faster than the average rate since 1993 of 3.2 mm/year. The
contribution of land ice melt from the world glaciers and the ice sheets has increased over
time and now dominate the sea level budget, rather than thermal expansion.

Shrinking Ice:

 Throughout 2015-2018, the Arctic’s average September minimum (summer) sea-ice

extent was well below the 1981-2010 average, as was the average winter sea-ice extent.
The four lowest records for winter occurred during this period. Multi-year ice has almost
disappeared. 

Antarctic February minimum (summer) and September maximum (winter) sea-ice extent
values have become well below the 1981-2010 average since 2016. This is in contrast to
the previous 2011-2015 period and the long term 1979-2018 period. Antarctic summer
 sea ice reached its lowest and second lowest extent on record in 2017 and 2018,
respectively, with 2017 also being the second lowest winter extent.

Ocean heat and acidity:

More than 90 % of the excess heat caused by climate change is stored in the oceans.
2018 had the largest ocean heat content values on record measured over the upper 700
meters, with 2017 ranking second and 2015 third.

The ocean absorbs around 30% of the annual anthropogenic emissions of CO2, thereby
helping to alleviate additional warming. The ecological costs to the ocean, however, are
high, as the absorbed CO2 reacts with seawater and changes the acidity of the ocean.
There has been an overall increase in acidity of 26% since the beginning of the industrial
revolution.

Extreme events:

More than 90 % of the natural disasters are related to weather. The dominant disasters
are storms and flooding, which have also led to highest economic losses. Heatwaves and
drought have led to human losses, intensification of forest fires and loss of harvest.

Heatwaves, which were the deadliest meteorological hazard in the 2015-2019 period,
affecting all continents and resulting in numerous new temperature records. Almost every
study of a significant heatwave since 2015 has found the hallmark of climate change,
according to the report.

The largest economic losses were associated with tropical cyclones. The 2017 Atlantic
hurricane season was one of the most devastating on record with more than US$ 125
billion in losses associated with Hurricane Harvey alone. On the Indian Ocean, in March
and April 2019, unprecedented and devastating back-to-back tropical cyclones hit
Mozambique.

Wildfires

Wildfires are strongly influenced by weather and climate phenomena. Drought

substantially increases the risk of wildfire in most forest regions, with a particularly
strong influence on long-lived fires. The three largest economic losses on record from
wildfires have all occurred in the last four years.

Climate change and extreme events

 According to the Bulletin of the American Meteorological Society, over the period 2015
to 2017, 62 of the 77 events reported show a significant anthropogenic influence on the
event’s occurrence, including almost every study of a significant heatwave. An increasing
number of studies are also finding a human influence on the risk of extreme rainfall
events.

HOW CLIMATE CHANGE IS AFFECTING OUR LIVES

HERE ARE THREE WAYS THAT CLIMATE CHANGE IS ALREADY AFFECTING
PEOPLE’S LIVES:
1. HEALTH

Climate action is just what the doctor ordered. And we mean that quite literally. Medical
professionals have increasingly been sounding the alarm about the risks and
consequences of continually burning fossil fuels.

2. HOME 

There’s really no place like home. But for many living in coastal communities, sea-level
rise could lead to an unwanted (and sudden) move.

3. FOOD

 No two people in this world are exactly the same. But there’s something that we all do,
regardless of our culture, language, or personality. We all eat. So it’s hard to ignore the
impacts of climate change on food.

GLOBAL WARMING EFFECTS

Here are some consequences that are documented in the Intergovernmental Panel
on Climate Change Special Report on Global Warming:

1.On biodiversity

The increase of temperatures and the climate upheavals disturb the ecosystems, modify
the conditions and cycles of plant reproduction. The scarcity of resources and climate
change are changing life habits and migratory cycles of animals. We are already
witnessing the disappearance of many species - including endemic species - or,
conversely, the intrusion of invasive species that threaten crops and other animals.

2.On oceans 

Because of global warming, permafrost and ice are melting massively at the poles,
increasing the sea level at a rate never known before. In a century, the increase reaches 18
cm (including 6 cm in the last 20 years). The worst case scenario is a rise of up to 1m by
2100.

3.On humans

Human beings are not spared by these upheavals. Climate change is affecting the global
economy. It is already shaking up social, health and geopolitical balances in many parts
of the world. The scarcity of resources like food and energy gives rise to new conflicts.

4.On the weather

For decades now, meteorologists and climatologists around the world have been watching
the effects of global warming on the weather phenomena. And the impact is huge: more
droughts and heat waves, more precipitations, more natural disasters like floods,
hurricanes, storms and wildfires, frost-free season, etc.

Global warming prevention:

1.Renewable energies
The first way to prevent climate change is to move away from fossil fuels. What are the
alternatives? Renewable energies like solar, wind, biomass and geothermal.

2.Energy & water efficiency 

Producing clean energy is essential, but reducing our consumption of energy and water
by using more efficient devices (e.g. LED light bulbs, innovative shower system) is less
costly and equally important.

Sustainable transportation icon

3.Sustainable transportation

 Promoting public transportation, carpooling, but also electric and hydrogen mobility, can
definitely help reduce CO2 emissions and thus fight global warming.

4.Sustainable infrastructure

In order to reduce the CO2 emissions from buildings - caused by heating, air
conditioning, hot water or lighting - it is necessary both to build new low energy
buildings, and to renovate the existing constructions.

Sustainable forest management icon

5.Sustainable agriculture & forest management

Encouraging better use of natural resources, stopping massive deforestation as well as

making agriculture greener and more efficient should also be a priority.

6.Responsible consumption & recycling

 Adopting responsible consumption habits is crucial, be it regarding food (particularly

meat), clothing, cosmetics or cleaning products. Last but not least, recycling is an
absolute necessity for dealing with waste. 

The Issue of Global Warming Due to the Modern Misuse of Techno-

Scientific Applications
Climate change has become undeniably one of the most important challenges for our
generation and the ones that follow.

.The problem that climate change represents is therefore very wide and has an effect on a
very broad range of human activities.

However, in spite of the importance of the historical and global parameters, it appears as
if the cause of the rise in temperature of our planet is first and foremost technological
(because of man-made carbon emissions) and that a technological solution would
consequently be needed.

After all, within the history of technology and science, every once in a while, a notable
breakthrough allows for the betterment of the human condition. Agriculture, electricity,
steam engines, atomic science, biotechnology, etc., mark our timeline.  
These breakthroughs have enriched the life of many, for the sake of ‘human’ needs,
complementing rather than overcoming the previous techniques and technologies. An
example of this complementary use is the ‘Green Revolution’ in which mechanized
agriculture played a major role in the 1960s to the 1990s, and that even saw countries
such as Mexico overproducing and therefore exporting some new types of wheat. These
past and contemporary techniques and technologies therefore play a major role in easing
our lives. It would therefore be logical to await for the next techno-scientific generation
to revolutionize our routines.