Global warming is caused by greenhouse gases like carbon dioxide trapping heat in the atmosphere. The industrial revolution marked the beginning of humans influencing global warming through burning fossil fuels and deforestation. Impacts of global warming include rising sea levels threatening coastal communities, extreme heat harming health, and declining crop yields due to higher temperatures. Solutions involve reducing emissions, stopping deforestation, and transitioning to more efficient transportation.

1. Global warming

2. What is global warming?
• 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.

3. Greenhouse gases
• A greenhouse gas is
a gas in an atmosphere
that absorbs and emits ra
diation within
the thermal
infrared range. The
primary greenhouse
gases in the Earth’s
atmosphere are water
vapor, carbon
dioxide, methane, nitrous
oxide, and ozone.

4. When Did Global Warming Start?
• The Earth has always had heating and cooling cycles that
are natural. The industrial revolution (at the turn of the
century - 1890-1910) is often taken to be the beginning
of humans influencing global warming.
• The industrial revolution denotes the period when
humans began to produce items using power-driven
machines. To power these machines energy was derived
from burning wood and coal. This increased the amount
of carbon dioxide, among other gases, present in the
atmosphere.
• The industrial revolution also denotes a period of
increased deforestation and pollution due to human
activities.

5. Impacts of global warming
1. Sea level:
• Two major mechanisms are causing sea level to rise. First,
shrinking land ice, such as mountain glaciers and polar ice
sheets, is releasing water into the oceans. Second, as ocean
temperatures rise, the warmer water expands. Trapped within
a basin bounded by the continents, the water has nowhere to
go but up.
Consequences:
• threats to coastal communities
- Some 40% of the world’s population lives within 62 miles of the
ocean.
• saltwater intrusion
- Sea-level rise can mean that saltwater intrudes into ground
water drinking supplies, contaminates irrigation supplies, or
overruns agricultural fields.

6. 2. Health:
• extreme heat
- If high temperatures, especially when combined with high
relative humidity, persist for several days and if nighttime
temperatures do not drop, extreme heat can be a killer.
• „natural” disasters
- Changing precipitation patterns and prolonged heat can
create drought, which can cause forest and peat fires.
• poor air quality
- Sunlight, warm air, and pollution from power plants and
cars burning coal and gasoline-combine to produce grand-
level ozone(smog),which humans experience as poor air
quality.
• spreading diseases
- Scientist expect a warmer world to bring changes in
„disease vectors”-the mechanisms that spread some
diseases. Insects previously stopped by cold winters are
already moving to higher latitudes (toward the poles).

7. 3. Health:
• reduces yields
- The productivity of crops and livestock, may decline
because of high temperatures.
• increased irrigation
- Regions of the world that now depend on rain-fed
agriculture may require irrigation, bringing higher costs
and conflict over access to water
• planting and harvesting changes
- Shifting seasonal rainfall patterns may delay planting
and harvesting

8. Solutions
• reduce emissions
- We must significantly reduce the amount of heat-
trapping emissions we are putting into the atmosphere.
• stop deforestation
- Reducing tropical deforestation can significantly lower
global warming emissions.
• greening transportation
- Switching to low-carbons fuels and more efficient
mass transportation systems.