Understanding Climate Change

Gord MillerEnvironmental Commissioner of Ontario

Climate Change is RealIt will Affect YOU!

. . . And maybe your dog too.

Absorbed Solar RadiationDetermines the Climate

Did you spend last summer in the water?

Or did you spend it bundled up?

Most ‘earthlings’ spent it on the beachMost ‘earthlings’ spent it on the beach

Temperature Anomalies Relative to 1952 – 1980 Average

It was the second warmest ‘earth’ summer in 130 years

Earth’s climate depends on the net amount of solar radiation that our planet absorbs

Climate change – fact or fiction?

= How much we get – how much we loseEarth Net Absorbed Solar Radiation

Why?Why?Climate has always changed on a long term cycle

How much we get(Solar energy hitting earth)

depends on earth’s. . .

OrbitEccentricity

Axis Tilt Solar Cycle

Eccentricity changes are on a 100,000 yr cycle

get picture for tilt

Earth Axis Tilt Changes from 24 degrees to 22.5 degrees40,000 year cycle - agrees with glacial cycles

Glacial periods end whenthe earthreaches

a position ofmaximum

tilt

Earth axis tilt now

From: James Hansen, Storms of My Grandchildren

Solar energy output is on an 11 year cycle

How much we keep depends on . . .

Albedo(sunlight reflected

by our planet)

Greenhouse Gases(capture infra-red light

and re-radiate it)

AlbedoOcean

Ice

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

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’

But . . .

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 !