The document discusses global warming and its causes and effects. It notes that the average global surface temperature has risen 0.74°C from 1906-2005, with warming almost doubling in the latter half. It identifies the major greenhouse gases that cause the greenhouse effect and contribute to warming, including water vapor, carbon dioxide, methane and ozone. It also discusses impacts on natural systems like rising sea levels and shrinking ice, as well as effects on ecosystems, food security and coastal habitats. The document outlines responses to global warming, including mitigation of emissions, adaptation strategies, and geoengineering approaches under investigation.

4. Topic of the Presentation is …

5. Global Warming
Global warming is the rise in the
average temperature of Earth's
atmosphere.

6.  The Earth's average surface temperature rose by 0.74±0.18 °C
over the period 1906–2005.
 The rate of warming over the last half of that period was
almost double

7. The greenhouse effect is a process by which thermal
radiation from a planetary surface is absorbed by
atmospheric greenhouse gases, and is re-radiated in
all directions.

8. Naturally occurring amounts of greenhouse gases have a mean warming
effect of about 33 °C (59 °F).The major greenhouse gases are
 Water vapor, which causes about 36–70% of the greenhouse effect
 Carbon dioxide (CO2), which causes 9–26%
 Methane (CH4), which causes 4–9%; and
 Ozone (O3), which causes 3–7%.

9.  Detection and attribution may also be applied to
observed changes in physical, ecological and social
systems.

10. Natural systems
Global warming has been detected in a number of natural
systems. e.g. sea level rise and widespread decreases in
snow and ice extent.

11. Ecological systems
climate change is expected to particularly affect certain
ecosystems, including tundra, mangroves, and coral
reefs.
Dissolved CO2 increases ocean acidity.

12. Observed and expected effects on social
systems
Food security- Under present trends, by 2030, decrease by
up to 30% while rice, millet and maize in South Asia could
decrease by up to 10%.
Habitat inundation- Maldives, Tuvalu and homelessness in
countries with low lying areas such as
Bangladesh

13. Responses to global warming
 Mitigation : The IPCC defines mitigation as activities that reduce
greenhouse gas (GHG) emissions. Many countries, both developing
and developed, are aiming to use cleaner, less polluting,
technologies.
 Energy-related carbon-dioxide (CO2) emissions in 2010 were the
highest in history, breaking the prior record set in 2008.

14. CON…
 Adaptation : A concept related to adaptation is "adaptive
capacity," which is the ability of a system (human, natural or
managed) to adjust to climate change

15.  Geoengineering : Geoengineering, the deliberate modification of
the climate, has been investigated as a possible response to global
warming, e.g. by NASA and the Royal Society