Download causes of climate change

Man-made causes of climate
change
 Burning fossil fuels
 Farming by-products
 Deforestation (no trees to take in CO2)
Earth’s climate history
 Has always been changing
NATURAL CAUSES OF CLIMATE
CHANGE
VOLCANOES
 Depends on type of eruption


Emit CO2- warms- mainly lava flows- long term
Ash blocks sun- cools- short term
Natural Climate Change: Volcanic Eruptions
Effect of ash and
SO2
Ex: Mt. Pinatubo (1991)
Backup site
Milankovitch cycles
 Earth orbit changes shape
 More elliptical= cooler
 Earth’s tilt changes
 Precession- tilt wobbles
 Less tilt= less seasons
Variation in Solar radiation
 Sunspots
 solar storms= hotter
 11 year cycle
Scientific American
 The authors calculated a net warming value of around
0.5 degree C since the 1950s. Changes in solar
radiation—a hypothesis for global warming proffered
by many climate skeptics—contributed no more than
around 0.07 degree C to the recent warming, the study
finds.
Polls of Climatologist
NASA
As the Earth moved out of ice ages over
the past million years, the global
temperature rose a total of 4 to 7 degrees
Celsius over about 5,000 years. In the past
century alone, the temperature has
climbed 0.7 degrees Celsius, roughly ten
times faster than the average rate of iceage-recovery warming.
U.S. EPA
Spiraling temperature GIF
 https://www.washingtonpost.com/news/energy-
environment/wp/2016/05/11/this-scientist-justchanged-how-we-think-about-climate-change-withone-gif/?tid=a_inl&utm_term=.e6b3c2af3ffb
So….
 Is the current climate change natural or man-made?
 article
Effects of global warming
 Rise in sea level
 Coasts underwater
 More storms/hurricanes
 Melt permafrost
 More deserts
 Coral reefs die (bleaching)
 Algae blooms
Land vs. sea ice
 Melting of sea ice will NOT effect sea level
 iceburgs
 Melting of land ice will effect sea level
 Antarctica/ Greenland
 Why?
 Could also cause global cooling (Day After Tomorrow)
Global warming can cause
global cooling?

Day after Tomorrow Trailer
(2004)
Glacier national Park, Montana
1938 vs. 2005
Alaska
1917 vs. 2005
Greenland
notice 2002-3
What can be done?
PARIS PROTOCOL
 2016
 Goal is to get global temps. below pre-industrial
revolution temps. (reduce by 2°C)
 195 countries
 US will reduce CO2 emissions by 26% by 2025
CON
What can we do to reduce greenhouse
gases? (add to review)
 Use less electricity
 More efficient appliances/light bulbs
 Alternative energy sources
 Drive less
 hybrids
I encourage you to do
more research!
Have an open mind!
Carbon footprint
 Your impact on GHGs.
 Extra credit!!