Download What are the anthropogenic causes of climate change?

Learning objective: Discuss the causes and
environmental consequences of global
climate change – anthropogenic causes
What is albedo?
What might be the consequences of
melting sea ice?
Global climate change
The changes in the global patterns of rainfall and
temperature, sea level, habitats and the
incidence of drought, floods and storms,
resulting from changes in the Earth’s
atmosphere, believed to be mainly caused by
the enhanced greenhouse effect.
Volcanic activity
Changes in long wave radiation
returned to space
Recap of the GHGs
•
•
•
•
•
•
What are the contributors and impacts of:
Carbon dioxide
Methane
Nitrous oxides
Chloroflorocarbons
Ozone
• Describe the sources of three of these using
p150-151
Greenhouse gases p150-151 Paul
Guinness
Greenhouse gas
Water vapour
Carbon dioxide
Methane
Chloroflorocarbons
Ozone
Source
Increase
• Highest rate of temperature change in late
20th – 21st century
• 1990s warmest decade on record
• Most increases in the mid and high latitudes
of northern hemisphere
• Argument that human activity has significantly
increased the amount of greenhouse gases in
the atmosphere
Water vapour, albedo, methane
Permafrost – methane store
Alternative views
most climate-change skeptics
do concede the planet is
warming
Instead, they debate the
cause, its potential impact,
and whether human
intervention can affect it.
some sceptics believe those who
blame the warming of the planet
on human activity are alarmists
They believe environmentalists use
catastrophic climate change to
place nature over the needs of
people and force the switch from
fossil fuels to alternative energy
sources, and tends toward "biggovernment intervention."
Most debate centres around:
• Are people responsible for the warming
trend?
• What impact will more warming will have
on the planet?
• Can anything be done about it?
Some of the scepticism comes from
suggestions that there may be flaws
in the IPCC data such as projecting
Himalayan glaciers could melt by
2035
They have also questioned the
accuracy of some of the climate
models.
Consequences
• Thermal expansion - 3mm per year
• Increased acidity – more CO2 absorbed creating carbonic
acid – impacts on coral
• Ice caps and glaciers melting
• Peat bog thawing
• Food
• Water
• Ecosystems
• Extreme weather
Use p 152 – 154 and annotate onto to your world map
On a post it write down one question
that you have about atmospheric
change