CLIMATE Climate describes the typical conditions of temperature,
relative humidity, cloudiness, precipitation, wind speed and
direction, and other meteorological factors that prevail
globally or regionally for extended periods.
Weather describes the hourly or daily conditions that people
experience each day.
Climate change is a long-term shift in weather conditions identified by changes in
temperature, precipitation, winds, and other indicators.
Climate change can involve both changes in average conditions and changes in
variability, including, for example, extreme events.
There have been long-term and short-term climate cycles for hundreds of millions of years.
Dramatic and rapid climatic changes.
IPCC report of 2007 said : Earth’s climate is changing rapidly and that human activities are
the primary factors causing this change.
These factors are external to the climate system, they are referred to as 'climate forcers‘
Not all of those factors that have been responsible for changes in earth's climate in the
distant past are relevant to contemporary climate change.
Burning fossil fuels
Forests are cut down or burned
can no longer store
carbon, and the carbon is
released to the atmosphere.
Act like a blanket and restrict
the rate at which Earth’s surface
can radiate heat to space
Result is global warming
Today, current levels of carbon
dioxide in the atmosphere are
higher than at any time during
the last 650,000 years.
2010 was the hottest year on
3. Burning of fossil fuels
Fossil fuels are the carbon-rich remains of
plants and animals that have been buried
and compressed under sediments for
millions of years.
more than 90% of greenhouse gas
emissions come from the combustion of
In 2007, the IPCC published a report
predicting that average global surface
temperatures will likely rise by an additional
2 to 11.5 degrees F (1.1 to 6.4 degrees C)
above the 1980s-1990s average by 2100.
Result in an increase in global sea level up
to two feet or more.
An enormous impact on our planet’s
people, ecosystems, cities, and energy use.
If we take aggressive action to reduce
emissions, the temperature change could be
If we continue on our present
course, however, the amount of change will
changes are anthropogenic