Transcript Understanding climate change - Environmental Commissioner of

Understanding Climate Change
Gord Miller
Environmental Commissioner of Ontario
Climate Change is Real
It will Affect YOU!
. . . And maybe
your dog too.
Absorbed Solar Radiation
Determines the Climate
Did you spend last summer in the water?
Or did you spend it bundled up?
Most
Most ‘earthlings’
‘earthlings’ spent
spent itit on
on the
the beach
beach
Temperature Anomalies Relative to 1952 – 1980 Average
It was the
second warmest ‘earth’ summer in 130 years
Climate change – fact or fiction?
Earth’s climate depends on the net amount of
solar radiation that our planet absorbs
Earth Net Absorbed Solar Radiation
= How much we get –
how much we lose
Climate has always changed on a long term cycle
Why?
How much we get
(Solar energy hitting earth)
depends on earth’s. . .
Orbit
Eccentricity
Axis Tilt
Solar Cycle
Eccentricity changes are on a 100,000 yr cycle
Earth Axis Tilt Changes from 24 degrees to 22.5 degrees
40,000 year cycle - agrees with glacial cycles
Glacial periods
end when
the earth
reaches
a position of
maximum
tilt
get picture for tilt
Earth axis
tilt now
Solar energy output is on an 11 year cycle
From: James Hansen, Storms of My Grandchildren
How much we keep
depends on . . .
Albedo
(sunlight reflected
by our planet)
Greenhouse Gases
(capture infra-red light
and re-radiate it)
Ice
Albedo
Ocean
Land
Presently the Earth should be gradually
sliding into a new ice age cycle but,
due to human activities…
“ice ages will never occur again – unless humans go extinct”
James Hansen
But . . .
The whole process has changed …
Greenhouses gases are accumulating at a
tremendous rate because of the
activities of humans …
This increases ‘how much we keep’
Figure SPM.6. Projected surface temperature changes for the late 21st century (2090-2099)
. Temperatures are relative to the period 1980-1999.
It’s your world . . .
Get involved !