Global Warming GOALS: Explain how the greenhouse effect works Describe why carbon dioxide is important in the atmosphere, but why scientists find it troubling that levels are rising Analyze what a warmer world might look like GLOBAL WARMING AND OZONE DEPLETION ARE VERY DIFFERENT!!!

Has Earth’s Climate Always Been Like Today’s? How is it possible that you can find shark teeth 20 miles from the beach in NJ? How is it possible that you find fossils of palm trees in parts of Canada? Today Global Average Temp = 59oF (2015)

Has Earth’s Climate Always Been Like Today’s? Over past 4.7 billion years climate has changed by Volcanic eruptions Changes in solar output Continents moving Meteorites Natural variations in CO2 Some changes slow, some quickly

Why does a greenhouse stay warm in the winter? Why does the inside of the car heat up quickly on a sunny day?

Greenhouse Effect Naturally occurring process in the atmosphere where gases trap in heat. Like a blanket covering planet Known about for over a century Without it Earth would be COLD

Greenhouse Gases Major greenhouse gases include Carbon Dioxide Water Vapor Methane CFCs All act to trap in heat

It’s All About Carbon When Carbon Falls in Love the World Heats Up

From the past we know that CO2 levels are tied closely to temperature

We know from the past that CO2 levels tied closely to temperature

Measuring CO2 Since 1958 in Mauna Loa Hawaii What does this data show? What trends does it show? Why does it go up and down each year?

CO2 rates rising quickly 1764 --- 276 ppm 1995 --- 360 ppm 2010 --- 390 ppm 2016 --- 404 ppm Chemist Charles Keeling’s CO2 measurements Why measure here?

Rising CO2 Levels Never 390 ppm in last 420,000 years (possibly 20 million years) Continue to rise rapidly Most CO2 in atmosphere is coming from burning fossil fuels like coal, oil and natural gas WHAT DOES THAT MEAN FOR THE FUTURE?

Where is the CO2 Coming From? 42% coal power plants 24% transportation 20% industrial processes 14% residential and commercial usages Exhale, drive, turn on light, burn log in fire 1 gallon of gas burned equals 20 pounds of CO2

What do higher CO2 levels mean for our future climate?

Global Warming Earth’s global average temperature continues to rise due to the increase in greenhouse gases in the atmosphere

How Can You Predict The Future? Very Complex Computer Models Those models are saying… It is likely that the world will warm 1.4oC to 5.8oC (2.5oF to 10.4oF) between 2000 and 2100

WHY CARE? It’s not like I can do anything. Plus, I Love my car. Some potential benefits of global warming

Consequences of a Warmer Earth 1) A Grand Experiment With Potentially Major Changes 2) Melting Ice = Higher Seas 3) Change in Weather Patterns 4) Human Health Problems 5) Agriculture Changes 6) Effects to plants and animals

Maple Trees in VT and NH have been producing less and less maple syrup over last few decades.

Both photos show Sperry Glacier in Montana’s Glacier National Park Both photos show Sperry Glacier in Montana’s Glacier National Park. Top: 1913: Bottom: 2008

Many major cities in the world are below, near or just above sea level.

Florida after sea level rise of 5 meters

Impacts on Organisms Habitats shift, usually toward the poles or to higher altitudes. Migrations start earlier in the spring. Loss of ice makes hunting seals difficult for polar bears

Impacts on the Oceans An increase in ocean temperature is associated with a process called coral bleaching. Changes in ocean acidity, resulting from an increase in dissolved carbon dioxide, can harm organisms.

Improve Efficiency of Cars

International Agreements What makes Global Warming a difficult issue for political leaders to deal with? 1) Complex issue 2) Consequences in future 3) Need behavior changes 4) International

Kyoto Protocol 1997 International Treaty accepted by 192 countries to limit CO2 pollution 1990 levels by 2012 U.S. did not ratify New treaties trying to negotiate

Global Warming: What does the future hold?