Transcript Long Term Ecological Monitoring at the Arctic Treeline, Churchill

Climate Change Basics
Steven Mamet
Department of Biology
University of Saskatchewan
LeeAnn Fishback
Scientific Coordinator
Churchill Northern Studies Centre
The last 125 years…
Global warming is now 0.8 °C in the past three
decades and 1.2 °C in the past century.
http://data.giss.nasa.gov/gistemp/graphs/
Where do scientists
measure temperature to get
a global average?
IPCC 2013
How does the average
global temperature of the
past 200 years compare
with the previous 2000?
The last 2000 years….
IPCC 2013
Could other things be
causing the earth’s
temperature to rise?
http://data.giss.nasa.gov/
http://lasp.colorado.edu/home/sorce/data/
IPCC 2013
Not due to solar
output increase
What is Solar Radiation?
Solar radiation is radiant energy
emitted by the sun, particularly
electromagnetic energy. About half of
the radiation is in the visible short-wave
part of the electromagnetic spectrum.
The other half is mostly in the nearinfrared part, with some in the
ultraviolet part of the spectrum
How does Carbon Dioxide
influence a planet’s
temperature?
Earth’s Atmospheric Content
What are the main
Greenhouse Gases?
How have CO2, CH4, and
N2O levels changed in
recent years?
How exactly do greenhouse
gases increase global
temperature?
Movement = Heat
Solid
Liquid
Gas
Still confused??? Have you
ever used one of these?
-=
How do we compare
measure the impact of
different greenhouse gases?
r
Since the industrial
revolution when have the
hottest recorded years
been?
Rank
1 = Warmest
Period of Record:
1880–2013
Year
Anomaly °C
Anomaly °F
1
2010
0.66
1.19
2
2005
0.65
1.17
3
1998
0.63
1.13
4 (tie)*
2013
0.62
1.12
4 (tie)*
2003
0.62
1.12
6
2002
0.61
1.10
7
2006
0.60
1.08
8 (tie)*
2009
0.59
1.07
8 (tie)*
2007
0.59
1.06
10 (tie)
2004
0.57
1.04
10 (tie)
2012
0.57
1.03
How much higher are CO2
levels today compared to
preindustrial levels? How
about CH4?
The last 430,000 years: Greenhouse gas forcing
Preindustrial Values:CO2 280 ppm CH4 660 ppb
To-day: ≈ 397 ppm CO2 >30%↑ ≈ 1830ppb CH4 >250% ↑
Petit et al 1999
How do CO2 levels today
compare with the past
800,000 years?
EP
Where do these regular
changes in global
temperature come from?
So where do all these green
house gases come from?
The Bottom line
 Greenhouse gases in our atmosphere are necessary
as they increase global temperatures to +15oC and
thereby permit and abundance of liquid water on
our planet
 From various proxy records, we know that levels
of CO2 fluctuate, and so does temperature
 The increase in CO2 by humans has greatly
accelerated what is otherwise a “natural” process
 Climate change is likely to continue accelerate in
coming years
Climate Change
 http://www.realclimate.org/
 http://berkeleyearth.org/