3. Weather & Climate Definitions
• Weather- “the state of the atmosphere
with respect to heat or cold, wetness or
dryness, calm or storm, clearness or
cloudiness”.
• Climate – “the average course or
condition of the weather at a place
usually over a period of years as
exhibited by temperature, wind velocity,
and precipitation”
• Weather & Climate Definitions
4. Higher pressure than what is
normal for that altitude.
What do you notice about the air in this region?
Brings clear skies and fair weather.
The sinking cold air warms as it does so and
becomes stable.
High Pressure
High Pressure
5. Low Pressure
• A low pressure region (depression
or cyclone) is caused by rising air.
• Clouds, rain, and very strong winds
occur.
• Why do you think that is?
6. Creating a Cloud
• Watch the cloud demonstration:
• What were the key ingredients in creating
the cloud?
• How is this representative of what might
take place in the atmosphere?
8. Temperature & Humidity
• Temperature - Air higher in pressure is
usually cooler air and air lower in pressure is
usually warmer air.
• What happens when the two meet?
• Humidity - How much water is in the air over
how much water could fit in the air (right
before the water begins to condense out of
the air).
• Dew point - Temperature at which the
moisture saturates the air is the dew point.
10. Wind
• Caused by the earth’s surface
being heated unevenly by the sun.
• Why would the earth’s surface heat
unevenly?
• How do you think this causes the
wind?
11. Thunderstorms
• What type of cloud causes these?
• Consists of gusty winds, heavy rain
and hail.
• Can result in a tornado
12. Lightning
• What did you observe in all the
lightning demonstrations? How does
this suggest lightning occurs?
• Interesting Fact: More people are
killed by lightning per year than
in tornadoes!!!
13. Atmosphere
• Troposphere - Most of the weather
occurs.
• Stratosphere - 19% of the atmosphere’s
gases are here; ozone layer is here
• Mesosphere - Most meteorites burn up
here.
• Thermosphere - High energy rays from
the sun are absorbed; hottest layer.
• Exosphere - Molecules from atmosphere
escape into space; satellites orbit here.
16. Greenhouse Gases
• Greenhouse gases - carbon dioxide,
methane, water vapor, nitrous oxide,
and fluorocarbons.
• Are they all bad? We will find out
through the lab.
• Retain the heat through a process
called the Greenhouse effect.
18. What is Climate Change?
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.
19. Research Project on Climate Change
undertaken by students of IX A
Students of Class IX A undertook a
research project to study the climate
change in Bangalore, the specific areas
of change, the reasons for this change,
its implications as well as strategies to
deal with Climate change.
Data was gathered via interviews with
senior citizens arranged by the local
residents association as well as with
officials from the Meteorological
Department.
20. Key Research Findings
• The city’s monthly mean maximum
temperature has been steadily on the rise. It
has increased by two to three degree Celsius
since 1960. The highest maximum temperature
in any given month has similarly risen by 1 to 2
degrees Celsius over the few decades.
• March and April, Bangalore's hottest months,
are only getting hotter.
21. Key Research Findings
• Over the last 20 years, the temperatures went
beyond 36.5 degrees Celsius on over nine
occasions, as opposed to only four such years in
the two preceding decades starting 1967.
• Rains in Bangalore have also turned
unpredictable. The months of September
&October are when the city receives the highest
rainfall in the year, about 195 mm and 180 mm
respectively on an average. However in recent
years Bangalore received only approximately
45.3 mm rain in September.
22. Key Research Findings
• Bangalore-The Urban Heat Island
The Centre's recording stations are placed in two
different locations in the city, one in the centre and the
other near the airport. The readings of these two
thermometers are always 1 or 2 degrees different, with
the one in the city centre recording higher temperatures
consistently.
This is a classic example of the "urban heat island"
effect, caused because Bangalore's green cover is
being replaced by concrete structures that absorb solar
radiation very rapidly.“
• Vehicular pollution, with carbon dioxide and other green
house gases that it generates, also has a big role to
play. Approximately 1.5 lakh to two lakh vehicles are
added to the city roads every year. Carbon dioxide
emissions trap heat, and this impacts climate.
•
23. Global Facts on Climate Change
• 1990s was the warmest decade in the last
millennium.
• 1998 was the warmest year.
• Snow cover is down 10% in the last 40 years.
• Arctic summer sea ice is likely to disappear in
second half of century.
• Carbon Dioxide levels in the Earth's atmosphere
have increased by 30% in the last 200 years
alone.
• Global temperature changes by the end of the
century could be as high as 6.4C.
• Sea levels around the world are likely to rise by
28-43cm by the end of the century.
24. Strategies to combat Climate Change
• Walk or bike instead of driving a car
• Use compact fluorescent light bulbs as these energy-
efficient
• Reduce heating and air-conditioning in your homes
• Use car pools whenever possible
• Buy local and seasonal produce
• Put a lid on vessels when cooking
• Turn off all electrical appliances instead of putting
them on standby when not in use
• Unplug electrical appliances when fully charged
• Keep the opening of fridge and freezer doors to the
minimum
• Use pressure cooker s as much as possible
RENEW, RECYCLE, REUSE
25. Some negative effects of Climate Change
• In Asia alone more than a billion people will be
affected by water shortage by 2050.
• Changes to India's annual monsoon are expected to
result in severe droughts and intense flooding in parts
of India.
• With more than 60% of agriculture dependent on rain-
fed crops, even modest alteration in the intensity,
frequency and timing of rainfall should cause a large
negative impact on food production.
• Increase in water borne diseases such as cholera and
hepatitis, as well as diseases carried by insects such
as malaria.
• Climate change is expected to contribute to air quality
problems and respiratory disorders will increase due
to warming-induced increases in the frequency of
smog.
26. YOU HAVE A CHOICE
You can choose to
SAVE THE EARTH
Take a pledge today to adopt the
strategies to reduce climate change
and let’s all join in the effort to
make the
earth smile again
29. Invention of agriculture
Accident and deliberate experiment
Two types of cultivation:
Vegetative planting: cloning from existing
plants
Seed agriculture: came later, planting of seeds,
practiced by most farmers today
30. Classifying agricultural regions
• Difference between LDCs (subsistence) and
MDCs (commercial)
• 1. Subsistence agriculture: growing food for
consumption by farmer’s family
• 2. Commercial agriculture: growing food for
sale off the farm (machinery and technology)
33. II. Agriculture in LDCs
• Shifting cultivation
– Humid low-latitude/tropical zones (high temp and
rainfall), low population density
– 2 types
• Slash-and-burn: clearing land by cutting vegetation and
burning debris (tropical zones)
• Rotation: using a field for a few years, then leaving it fallow
for many years
34. Agribusiness includes processing, packaging, storing,
distributing, and retailing; tractor manufacturing,
fertilizer production, seed distribution…
Farmers are less than 2% of the US labor force
But 20% of US labor works in food production and
service
Many aspects of agribusiness are controlled by large
corporations
Agribusiness
35. • Intensive subsistence agriculture
– Farmers must work more intensively to subsist on a
parcel of land
– Farms are smaller, so more pressure for productivity
– Practiced in densely populated areas (East, South,
and Southeast Asia)
– Wet rice dominant: mostly in river valleys and deltas,
or in flat or terraced fields
– Wet rice not dominant: climate prevents farmers from
growing wet rice in parts of Asia, where summer
precipitation is low and winters are harsh
36. • Plantation farming
– A form of commercial agriculture in tropics and
subtropics (Latin America, Africa, Asia)
– Mostly in LDCs, but many owned by people in MDCs,
and most products for sale in MDCs
– Plantation: a large farm that specializes in one or two
crops
37. – Crop rotation systems
• Farm split into fields, and each field planted on a planned
cycle, often several years (1 year fallow and cycle is
repeated)
• Different from shifting agriculture in LDCs because LDCs
leave fields fallow for many years and productivity is lower
• 2-field crop rotation system (Northern Europe, 5th century)
– Cereal grain planted in Field A for one year, Field B fallow
• 3-field system (8th century)
– Field 1 planted with a winter cereal, Field 2 a spring cereal,
Field 3 left fallow
• 4-field system (NW Europe, 18th century)
– First year: root crop in Field 1, cereal in Field 2, rest crop in
Field 3, and cereal in Field 4
– Second year: cereal in Field 1, rest crop in 2, cereal in 3, and
root in 4
