1. Atmospheric Changes and the Greenhouse Effect
The history of climate

2. Past Atmospheric Changes
What causes changes in our atmosphere?
Abiotic Factors:
Temperature and precipitation
Biotic Factors:
Plants and Animals
We can’t measure past precipitation , but we can measure temperature and atmospheric gases
Proxy data: preserved physical characteristics of the environment that can stand in for direct measurements (tree rings, pollen fossils, sediments)
Ice Cores: Used to measure concentrations of ancient gases
Must use as many forms of proxy data as possible since the accuracy of any particular one can’t be counted on 100% of the time.

4. The Greenhouse Effect
What is the greenhouse effect?
Natural warming of the atmosphere depending upon the concentration of greenhouse gasses
Necessary for survival!!!!!
Without the greenhouse effect Earth would be 33°C cooler (91.4°F)
Our average temp allows
Water to be liquid!!!

6. Greenhouse effect Important gasses (must have 2 or more bonds) H2O CO2
Solar energy (light) that reaches the earth is converted into (heat) infrared.
This infrared radiation has a hard time passing through the gasses in our atmosphere thereby trapping heat and keep the planet about 30 degrees (Celsius) warmer
Important gasses (must have 2 or more bonds)
H2O
CO2
CH4
N2O O3