CAUSES OF CLIMATE CHANGE Manmade causes of climate

CAUSES OF CLIMATE CHANGE

Man-made causes of climate change Burning fossil fuels Farming by-products Deforestation (no trees to take in CO 2)

Earth’s climate history Has always been changing

NATURAL CAUSES OF CLIMATE CHANGE

VOLCANOES Depends on type of eruption Emit CO 2 - warms- mainly lava flows- long term Ash blocks sun- cools- short term

Natural Climate Change: Volcanic Eruptions Effect of ash and SO 2 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 1950 s. 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 ice-agerecovery warming.

U. S. EPA

Spiraling temperature GIF https: //www. washingtonpost. com/news/energyenvironment/wp/2016/05/11/this-scientist-justchanged-how-we-think-about-climate-change-withone-gif/? tid=a_inl&utm_term=. e 6 b 3 c 2 af 3 ffb

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)

Current state of glaciers

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 CO 2 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!!