Rama Khadka's presentation discusses ozone layer depletion and global warming. It defines good and bad ozone, and explains how CFCs released from products deplete the stratospheric ozone layer, increasing UV rays at the surface. Climate change effects include rising seas, extreme weather, species loss. While international agreements aim to reduce emissions, urgent action is still needed given the threats of global warming. The presentation notes Nepal's vulnerability to climate impacts like changing rainfall patterns.

1. Presented by:
Rama Khadka

2. Before we start some question …..
– Have you ever felt the sun's intensity ripping through your skin on
a hot afternoon?
– Why it is not too cold at night when there is no sun in the sky??
– What is the concentration of carbondioxide in atmosphere now??
– What is the annual temperature increase in the earth???
– What in the annual temperature increase in Nepal????
– Why there is a change like this…..

4. Ozone Layer depletion

5. What is Ozone?
Ozone is a natural gas composed of three atoms of oxygen. Its
chemical symbol is O3. It is blue in color and has a strong odour.
Normal oxygen (O2), which we breathe, has two oxygen atoms and is
colorless and odorless. Environmental scientists have classified O3
into two: Good Ozone and Bad Ozone.

7. Good Ozone
– Good ozone (also called Stratospheric Ozone) occurs naturally in
the upper Stratosphere. The stratosphere is the layer of space 6
to 30 miles above the earth's surface.
Where does good Ozone come from?
– When UV light strikes (Oxygen) O2 molecules, they split into two
individual O atoms — O and O. When one of the O atoms
combine with O2 molecule, ozone (O3) is created.

9. Even though Ozone is only a small part of the gases in this layer, it
plays a vital role because it shields us from the sun's harmful UV
rays. It is called Good Ozone, for obvious reasons—because it
protects humans, life and animals on earth.

10. Bad Ozone
– Bad Ozone is also known as Tropospheric Ozone, or ground level
ozone. This gas is found in the troposphere, the layer that forms
the immediate atmosphere.
Where does bad ozone come from?
– Each time there is a reaction of chemicals such as those found in
cars, power plants and factory emissions, in the presence of
sunlight (UV light) Bad Ozone is created, so it can be said that Bad
Ozone does not exist naturally. Bad ozone contaminates (dirties)
the air and contributes to what we typically experience as "smog”

11. The Ozone Layer
– This is simply a layer in the stratosphere containing a relatively high
concentration of ozone.

12. What is Ozone Depletion?
– Ozone layer depletion, is simply the wearing out (reduction) of the
amount of ozone in the stratosphere. Ozone depletion has been
pinned down to one major human activity as its cause.
– Industries that manufacture things like insulating foams, solvents,
soaps, cooling things like Air Conditioners, Refrigerators and ‘Take-
Away’ containers use something called chlorofluorocarbons (CFCs).
These substances are heavier than air, but over time, (2-5years)
they are carried high into the stratosphere by wind action.

14. – Scientific evidence indicates that stratospheric ozone is being
destroyed by a group of manufactured chemicals, containing
chlorine and/or bromine. These chemicals are called "ozone-
depleting substances" (ODS).
– ODS are very stable, nontoxic and environmentally safe in the
lower atmosphere, which is why they became so popular in the
first place. However, their very stability allows them to float up,
intact, to the stratosphere.

15. – The main ODS are chlorofluorocarbons (CFCs),
hydrochlorofluorcarbons (HCFCs), carbon tetrachloride and
methyl chloroform. Halons (brominated fluorocarbons) also play a
large role.
– Their application is quite limited. But the problem with halons is
they can destroy up to 10 times as much ozone as CFCs can. For
this reason, halons are the most serious ozone-depleting group of
chemicals.

16. Health and environmental effect of ozone layer depletion
Reductions in stratospheric ozone levels will lead to higher levels
of UVB reaching the Earth's surface.
Effect on human
 Laboratory and epidemiological studies demonstrate that UVB
causes nonmelanoma skin cancer and plays a major role in
malignant melanoma development.
 In addition, UVB has been linked to cataracts -- a clouding of the
eye’s lens.

17.  Effect on plants
 Plant growth, as well as its physiological and developmental processes are all
affected negatively.
 These include the way plants form, timing of development and growth, distribution
of plant nutrients and metabolism, etc.
 Effect on biochemical cycles
 Increases in solar UV radiation could affect terrestrial and aquatic biogeochemical
cycles, thus altering both sources and sinks of greenhouse and chemically-
important trace gases e.g., carbon dioxide (CO2), carbon monoxide (CO), carbonyl
sulfide (COS) and possibly other gases, including ozone.

18. Effect on marine Ecosystem
 Scientists have demonstrated a direct reduction in
phytoplankton production due to ozone depletion-related
increases in UVB.
 Phytoplankton form the foundation of aquatic food webs. One
study has indicated a 6-12% reduction in the marginal ice zone.
 Solar UVB radiation has been found to cause damage to early
developmental stages of fish, shrimp, crab, amphibians and
other animals. The most severe effects are decreased
reproductive capacity and impaired larval development.

19. Effect on materials
 Synthetic polymers, naturally occurring biopolymers, as well as
some other materials of commercial interest are adversely
affected by solar UV radiation.
 Today's materials are somewhat protected from UVB by special
additives. Therefore, any increase in solar UVB levels will
therefore accelerate their breakdown.

20. Protecting Ozone layer
Here are five ways in which we can contribute to protecting the
ozone layer and our precious Earth:
Limit private vehicle driving
Use eco-friendly household cleaning products
Avoid using pesticides
Developing stringent regulations for rocket launches
Banning the use of dangerous nitrous oxide

21. Global warming

22. Greenhouse effect
– In a simple term the greenhouse effect can be defined as a
blanket around the earth.
– A layer of greenhouse gases – primarily water vapor, and
including much smaller amounts of carbon dioxide, methane
and nitrous oxide – acts as a thermal blanket for the Earth,
absorbing heat and warming the surface to a life-supporting
average of 59 degrees Fahrenheit (15 degrees Celsius).

24. Greenhouse Gases
– Greenhouse gases are those that absorb and emit infrared radiation
in the wavelength range emitted by Earth. In order, the most
abundant greenhouse gases in Earth's atmosphere are:
– Water vapor (H2O)
– Carbon dioxide (CO2)
– Methane (CH4)
– Nitrous oxide (N2O)
– Ozone (O3)
– Chlorofluorocarbons (CFCs)

26. Let us remember our evolution

27. And we have changed

28. To

29. But during this revolution we have
changed many other things also like
– Have produced a 40% increase in the atmospheric
concentration of carbon dioxide.
– The concentration of carbon dioxide reach from 280 ppm in
1750 to 400 ppm in 2015.

30. – Which result from the Strengthening of the greenhouse effect
through human activities is known as the enhanced or
anthropogenic greenhouse effect.
– When fossil fuels - coal, oil and natural gas - are burnt they release
CO2 into the atmosphere. Because of this the layer of greenhouse
gas is getting thicker, which is in turn making the Earth warmer.

31. – The global average (land and ocean) surface temperature shows a
warming of 0.85 [0.65 to 1.06] °C in the period 1880 to 2012, based
on multiple independently produced datasets.

32. – Global Warming is the increase of Earth's average surface
temperature due to effect of greenhouse gases, such as carbon
dioxide emissions from burning fossil fuels or from deforestation,
which trap heat that would otherwise escape from Earth.

33. – According to the International Energy Agency the power sector is
responsible for 37% of all man-made Carbon Dioxide (CO2)
emissions. It creates about 23 billion tons of CO2 emissions per
year – in excess of 700 tons a second.
– In turn, this CO2 continues to heat up our planet which poses an
unprecedented threat to us and the environment.
– So, generating electricity through the burning of fossil fuels, in
particular carbon-heavy coal, has a greater impact on the
atmosphere than any other single human activity.

35. Effects of climate change

36. – Rising Seas--- inundation of fresh water marshlands (the everglades), low-
lying cities, and islands with seawater.
– Changes in rainfall patterns --- droughts and fires in some areas, flooding
in other areas.
– Increased likelihood of extreme events--- such as flooding, hurricanes,
etc.
– Melting of the ice caps --- loss of habitat near the poles. Polar bears are
now thought to be greatly endangered by the shortening of their feeding
season due to dwindling ice packs.
– Melting glaciers - significant melting of old glaciers is already observed.

37. – Widespread vanishing of animal populations --- following widespread
habitat loss.
– Spread of disease --- migration of diseases such as malaria to new, now
warmer, regions.
– Bleaching of Coral Reefs due to warming seas and acidification due to
carbonic acid formation --- One third of coral reefs now appear to have
been severely damaged by warming seas.
– Loss of Plankton due to warming seas --- Which is a foundation of aquatic
food web.
In short the single but threatening effect of global warming is Climate change.

38. In context of Nepal
– Nepal is responsible for 0.025 % of global carbon emission
– And has been listed as a fourth vulnerable country due to climate change.
– As the average annual temperature is increasing by 1.5 °C .
– Frequent news on headline like changed rain pattern, floods, drought,
vanishing of apple orchids from Mustang village, tree line shifting etc. are
now common.
– In short there is an enough evidence of effects of climate change in Nepal
too.

39. What we have done so far???
– Many actions were taken in the past few years as mitigation and
adaptation for the global warming and climate change after The
United Nations Framework Convention on Climate Change
(UNFCCC) in 1992.
– The main current international agreement on combating climate
change is the Kyoto Protocol, which came into force on 16
February 2005.

40. – For countries in the EU, this involves a commitment to reducing carbon
emissions by 12.5% by 2012. While the protocol is binding, it isn't
compulsory for countries to actually sign up, and, notably, several large
counties including the US haven't committed to signing up to the scheme as
yet, despite growing international pressure.
– But the scenario have been changed the existing and possible effects of
climate change can be very dangerous for the human being.
– So a concrete action with the climate justice for the developing countries
like Nepal is MUST.

41. – Most recently, a UN conference in Bali reached a deadlock after
the US refused to support a follow-up deal to Kyoto, which would
have seen countries have to reduce carbon emissions by up to
40% by 2020.
– For our future, the Conference of parties (COP) 21 is on its way in
Paris and the world is expecting a new climate treaty as a drastic
awareness have been seen among the population around the
world.

43. Only one planet
No plan B…..

44. References
– http://www.nmsea.org/Curriculum/Primer/Global_Warming/fossil_fuels_a
nd_global_warming.htm
– http://www.nrdc.org/globalwarming/
– https://en.wikipedia.org/wiki/Global_warming
– https://en.wikipedia.org/wiki/Ozone_depletion
– http://environment.nationalgeographic.com/environment/global-
warming/ozone-depletion-overview/