Global warming refers to the long-term rise in Earth's average temperature due to human activities like burning fossil fuels. Since pre-industrial times, human activities have increased Earth's average temperature by about 1 degree Celsius. It is unequivocal that human influence has warmed the atmosphere, ocean, and land. The greenhouse effect occurs naturally and makes Earth habitable, but human emissions of greenhouse gases like carbon dioxide are enhancing the effect and causing global warming. Continued emissions will lead to more extreme weather, higher sea levels, and other damaging impacts. Addressing global warming will require international cooperation on clean energy and adaptation efforts.

1. GLOBAL WARMING

2.  Global warming is the long-term heating of Earth’s climate system
observed since the pre-industrial period (between 1850 and 1900) due to
human activities, primarily fossil fuel burning, which increases heat-
trapping greenhouse gas levels in Earth’s atmosphere. The term is
frequently used interchangeably with the term climate change, though
the latter refers to both human- and naturally produced warming and the
effects it has on our planet. It is most commonly measured as the average
increase in Earth’s global surface temperature.
 Since the pre-industrial period, human activities are estimated to have
increased Earth’s global average temperature by about 1 degree Celsius
(1.8 degrees Fahrenheit), a number that is currently increasing by 0.2
degrees Celsius (0.36 degrees Fahrenheit) per decade. It is unequivocal
that human influence has warmed the atmosphere, ocean, and land.
WHAT IS GLOBAL WARMING

3.  The greenhouse effect is a process that occurs when gases in Earth's
atmosphere trap the Sun's heat. This process makes Earth much warmer
than it would be without an atmosphere. The greenhouse effect is one of
the things that makes Earth a comfortable place to live.
 The greenhouse effect works much the same way on Earth.
Gases in the atmosphere, such as carbon dioxide, trap heat
similar to the glass roof of a greenhouse. These heat-trapping
gases are called greenhouse gases.
 During the day, the Sun shines through the atmosphere. Earth's
surface warms up in the sunlight. At night, Earth's surface cools,
releasing heat back into the air. But some of the heat is trapped
by the greenhouse gases in the atmosphere. That's what keeps
our Earth a warm and cozy 58 degrees Fahrenheit (14 degrees
Celsius), on average.
GREENHOUSE EFFECT

4. THE IMAGE SHOWS THE PRESENT CARBON CYCLE. THE DISRUPTION OF
WHICH LEADS TO INCREASED EMISSION OF CARBON DIOXIDE WHICH
ULTIMATELY LEADS TO RISE IN GLOBAL TEMPERATURES.

5.  GREENHOUSE
Cause 1: Variations in the Sun's Intensity.
Cause 2: Industrial Activity.
Cause 3: Agricultural Activity.
Cause 4: Deforestation.
Cause 5: Earth's Own Feedback Loop.

6. THE IMAGE BELOW DESCRIBES THE GREENHOUSE EFFECT
AND THE ROLE OF GREENHOUSE GASES

7.  More frequent and severe weather. Higher temperatures are worsening many
types of disasters, including storms, heat waves, floods, and droughts.
 Higher death rates.
 Dirtier air.
 Higher wildlife extinction rates.
 More acidic oceans.
 Higher sea levels.

9. 800 600 400 200 0
CO
2
(ppmv)
Thousands of Years Before Present
240
300
270
210
180
Temp.
Proxy
THE IMAGE SHOWS THE CONCENTRATION OF
CO2 IN THE ATMOSPHERE OVER A PERIOD OF
TIME IF EMISSIONS CONTINUE UNALTERED.

11. THE GRAPH SHOWS THE GLOBAL MEAN TEMPERATURE
DURING THE PERIOD 1961-90
The Modern Temperature Trend
Tracking the world's average temperature from the late 19th century, people in the 1930s
reported there had been a pronounced warming trend. During the 1960s, weather experts
found that over the past couple of decades the trend had shifted to cooling. With a new
awareness that climate could change in serious ways, in the early 1970s some scientists
a continued gradual cooling, perhaps a phase of a long natural cycle or perhaps caused
by human pollution of the atmosphere with smog and dust. Others insisted that the
effects of such pollution were temporary, and humanity's emission of greenhouse gases
would bring warming over the long run. All of them agreed that their knowledge was
primitive and any prediction was guesswork. But understanding of the climate system
was advancing swiftly. The view that warming must dominate won out in the late 1970s
as it became clear that the cooling spell (mainly a Northern Hemisphere effect) had
indeed been a temporary distraction. When the rise continued into the 21st century,
setting new records decade after decade, the heat penetrating even into the ocean
depths, scientists realized that it signaled a profound change in the climate system.
Painstaking historical studies, using everything from ship logs to ice caps to ocean
to tree rings, proved that nothing like the recent rise had been seen for millennia.
The specific pattern of changes matched the predicted effects of humanity’s
greenhouse gas emissions.

12. THE GRAPH SHOWS STANDARD DEVIATION OF THE
TEMPERATURE FROM GLOBAL AVERAGES.
When did global temperatures start rising? If you say “in about 1980”,
take another look. Re-read the heading and the line below the graph.
When did temperatures first start rising? What was happening at that
time that may have caused the global average temperature to rise?
This week’s graph is a time series for 1880 – 2019 with bars. The
baseline average temperature is from 1951 - 1980. Last year, The New
York Times published a 1880 - 2018 time series graph with points. The
baseline was 1880 – 1899. The data for the two graphs is the same
except that this week’s graph includes 2019. But, there are other
differences between the two graphs.
If this week’s graph used the 1880 – 1899 baseline, how would the graph
change? Why do you think the designers used the 1951 - 1980 baseline?
Scientists have determined that climate has become more extreme and
more variable. Which graph best shows that temperature has become
more extreme? Which graph best shows that temperature has become
more variable? Explain your answers.

13. TYPES OF WATER POLLUTION
 Industrial Waste
 Marine Dumping
 Sewage and Wastewater
 Oil Leaks and Spills
 Agriculture
 Global Warming
 Radioactive Waste

14. CARBON SEQUESTRATION
Carbon sequestration
is a term that describes
processes that remove
carbon from the
atmosphere.
Seeding oceans with iron
Solar shades
Geoengineering

15. The ‘Conclusion’ confirms that global warming is the major challenge for our
global society. There is very little doubt that global warming will change our climate in
the next century. So what are the solutions to global warming? First, there must be an
international political solution. Second, funding for developing cheap and clean energy
production must be increased, as all economic development is based on increasing
energy usage. We must not pin all our hopes on global politics and clean energy
technology, so we must prepare for the worst and adapt. If implemented now, a lot of the
costs and damage that could be caused by changing climate can be mitigated.
CONCLUSION OF GLOBAL WARMING

16. THANK YOU