Presentation on theme: " The difference between weather and climate is a measure of time. Weather is what conditions of the atmosphere are over a short period of time, and climate."— Presentation transcript:
The difference between weather and climate is a measure of time. Weather is what conditions of the atmosphere are over a short period of time, and climate is how the atmosphere "behaves" over relatively long periods of time. Climate is usually over a 30 day period or longer.
The Sun Atmospheric Gases (Greenhouse Gases) Volcanic Eruptions Surface Albedo (reflectivity) snow cover Ocean Currents Changes in earth’s orbit (Milankovitch Cycles) Meteorite Impacts Living organisms (plants, animals, microbes)
http://www.rockymountainstars.com/Pre_AP _Geo_Solar_Variation.htm http://www.rockymountainstars.com/Pre_AP _Geo_Solar_Variation.htm 1645 to 1750 called the Maunder Minimum A period of little to no sunspot activity.
Small changes in any of these energy budget parameters will cause the earth to heat up or cool off. Example: More ice would increase reflectivity or albedo creating a positive feedback which would lower the global temperature.
In 1915 Mt. Tombora erupted in Indonesia. This was the largest eruption in 1,300 years. The dust surrounded the globe which created a constant fog like haze which blocked out sunlight. 1916 was known as the year without a summer. A deep frost occurred over much of the US in June killing off most of the crops.
Long term changes in the earth’s orbit (eccentricity) around the sun and axial tilt can change the overall heat balance of our planet. A decrease in the axial tilt will cause less extreme seasons in the upper latitudes. These resulting cooler summers do not melt all the snow & ice from the previous winter which over time can lead to an ice age.
The great oxygen event occurred 2.4 billion years ago. Oxygen released from photosynthetic blue- green algae combined with iron in the sediment to create red & black bands of oxidized iron. The banding may be caused by seasonal variations in photosynthesis and oxygen production by algae.