Ozone layer depletion

1. Atmospheric Pollution
Unit# 3.2
Presentation by: Ms. Sadaf Anwer
O’Level Environmental Management teacher

2. Unit 3.2: Atmospheric Pollution
 Global Warming
 Ozone depletion
 Urban Problems
 Temperature Inversion
 Smog
 Photochemical Smog
 Urban heat wave

3. THE GREENHOUSE EFFECT
These gases, which are all naturally occurring, act as a
blanket, trapping in the heat and preventing it from
being reflected too far from the Earth. They keep the
Earth's average temperature at about 15°C: warm
enough to sustain life for humans, plants and animals.
Without these gases, the average temperature would
be about -18°C... too cold for most life forms. This
natural warming effect is also sometimes called the
greenhouse effect.

5. CLIMATE CHANGE OR GLOBAL WARMING?
 The terms "climate change" and "global warming" are often used
interchangeably.
 Generally WWF use the more scientifically accurate term "climate
change", but we often use "global warming" as it remains popular in
public discourse.
This definition from the NASA website is perhaps the best way to
approach the two labels.
 "Global warming refers to surface temperature increases, while climate
change includes global warming and everything else that increasing
greenhouse gas amounts will affect."

6. Global warming is expected to have
far-reaching, long-lasting and, in
many cases, devastating
consequences for planet Earth.
For some years, global warming, the
gradual heating of Earth's surface,
oceans and atmosphere, was a topic
of heated debate in the scientific
community.

7. Causes
Today, the overwhelming consensus of researchers
is that global warming is real and is caused by
human activity, primarily the burning of fossil
fuels that pump carbon dioxide (CO2), methane
and other greenhouse gases into the atmosphere.

8. Watch video from link
 https://www.youtube.com/watch?v=oJAbATJCugs

10. Culprit coal
 The biggest climate polluter is the global
power sector which generates around 40%
of all global electricity from coal. We need
electricity - but when you take into
account the true cost of coal there are
much better ways to get it!
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
tonnes of CO2 emissions per year – in excess
of 700 tonnes a second.

13. Effects:
Increase in average temperatures and temperature extremes
 The average global temperature has increased by about 1.4 degrees Fahrenheit
(0.8 degrees Celsius) over the past 100 years, according to the National
Oceanic and Atmospheric Administration (NOAA).
Extreme weather events
Ice melt
 One of the most dramatic effects of global warming is the reduction in Arctic
sea ice: In 2012, scientists saw the smallest amount of Arctic ice cover ever
recorded. Most analyses project that, within a matter of years, the Arctic Sea
will be completely ice-free during the summer months.
 Glacial retreat, too, is an obvious effect of global warming. Only 25 glaciers
bigger than 25 acres are now found in Montana's Glacier National Park, where
about 150 glaciers were once found, according to the U.S. Geological Survey.
A similar trend is seen in glacial areas worldwide

14. Effects
Sea levels and ocean acidification
 As ice melts, the ocean levels rise. In 2014, the World Meteorological Organization
reported that sea level rise accelerated .12 inches (3 millimeters) per year on average
worldwide. This is around double the average annual rise of .07 in (1.6 mm) in the
20th century.
 Sea level isn't the only thing changing for the oceans due to global warming. As levels
of CO2 increase, the oceans absorb some of that gas, which increases the acidity of
seawater. Werne explains it this way: "When you dissolved CO2 in water, you get
carbonic acid. This is the same exact thing that happens in cans of soda. When
you pop the top on a can of Dr Pepper, the pH is 2 — quite acidic." Since the
Industrial Revolution began in the early 1700s, the acidity of the oceans has increased
about 25 percent, according to the EPA. "This is a problem in the oceans in large
part because many marine organisms make shells out of calcium carbonate (think
corals, oysters), and their shells dissolve in acid solution," said Werne. "So as we
add more and more CO2 to the ocean, it gets more and more acidic, dissolving more
and more shells of sea creatures. It goes without saying that this is not good for their
health."
 If current ocean acidification trends continue, coral reefs are expected to become
increasingly rare in areas where they are now common, including most U.S. waters,
the EPA reports.

15. Effects
Plants and animals
Warmer temperatures will also expand the range of
many disease-causing pathogens that were once
confined to tropical and subtropical areas, killing off
plant and animal species that formerly were protected
from disease.
These and other effects of global warming, if left
unchecked, will likely contribute to the disappearance
of up to one-half of Earth's plants and one-third of
animals from their current range by 2080, according to
a 2013 report in the journal Nature Climate Change.

16. Social Effects
 As dramatic as the effects of climate change are expected to be on the natural world, the
projected changes to human society may be even more devastating.
 Agricultural systems will likely be dealt a crippling blow. Though growing seasons in
some areas will expand, the combined impacts of drought, severe weather, lack of snowmelt,
greater number and diversity of pests, lower groundwater tables and a loss of arable land could
cause severe crop failures and livestock shortages worldwide.
 North Carolina State University also notes that carbon dioxide is affecting plant growth. Though
CO2 can increase the growth of plants, the plants may become less nutritious.
 In addition to less nutritious food, the effect of global warming on human health is also expected
to be serious. The American Medical Association has reported an increase in mosquito-
borne diseases like malaria and dengue fever, as well as a rise in cases of
chronic conditions like asthma, are already occurring, most likely as a direct result of
global warming.
 This loss of food security may, in turn, create havoc in international food markets and
could spark famines, food riots, political instability and civil unrest worldwide,
according to a number of analyses from sources as diverse as the U.S Department of Defense,
the Center for American Progress and the Woodrow Wilson International Center for Scholars.
 Many of these expected effects are the result of exhaustive scientific research and climate
models, and the fact that most of them are already being observed gives additional credibility to
the projected effects of global warming and climate change.